Width should have no side effects

Makefile

@@ -11,22 +11,19 @@ ifeq ($(OS), Linux)
 	BUNDLENAME = $(APP)-$(OS)-$(DISPDRIVER)-$(ARCH)-$(VERSION)
 endif
 
-CORES = ppsspp dolphin atari800 bluemsx citra swanstation fbneo fceumm flycast gambatte gearsystem genesis_plus_gx handy lutro mednafen_ngp mednafen_pce mednafen_pce_fast mednafen_pcfx mednafen_psx mednafen_saturn mednafen_supergrafx mednafen_vb mednafen_wswan mgba melonds mupen64plus_next np2kai o2em pcsx2 pcsx_rearmed picodrive pokemini prosystem snes9x stella2014 vecx virtualjaguar
+CORES = atari800 bluemsx swanstation fbneo fceumm gambatte gearsystem genesis_plus_gx handy lutro mednafen_ngp mednafen_pce mednafen_pce_fast mednafen_pcfx mednafen_psx mednafen_saturn mednafen_supergrafx mednafen_vb mednafen_wswan mgba melonds mupen64plus_next np2kai o2em pcsx_rearmed picodrive pokemini prosystem snes9x stella2014 vecx virtualjaguar
 
 ifeq ($(ARCH), arm)
-	CORES := $(filter-out citra dolphin flycast mednafen_pcfx mednafen_saturn melonds mupen64plus_next pcsx2 ppsspp swanstation,$(CORES))
+	CORES := $(filter-out swanstation,$(CORES))
+	CORES := $(filter-out mupen64plus_next,$(CORES))
+	CORES := $(filter-out mednafen_pcfx,$(CORES))
+	CORES := $(filter-out mednafen_saturn,$(CORES))
+	CORES := $(filter-out melonds,$(CORES))
 endif
 ifeq ($(ARCH), arm64)
-	CORES := $(filter-out pcsx2,$(CORES))
-	ifeq ($(OS), Linux)
-		CORES := $(filter-out mupen64plus_next,$(CORES))
-	endif
-endif
-ifeq ($(OS), OSX)
-	CORES := $(filter-out pcsx2,$(CORES))
-	ifeq ($(ARCH), x86_64)
-		CORES := $(filter-out citra,$(CORES))
-	endif
+	CORES := $(filter-out mednafen_saturn,$(CORES))
+	CORES := $(filter-out mupen64plus_next,$(CORES))
+	CORES := $(filter-out picodrive,$(CORES))
 endif
 
 DYLIBS = $(addprefix cores/, $(addsuffix _libretro.dylib,$(CORES)))

README.md

@@ -4,7 +4,7 @@ Ludo is a work in progress libretro frontend written in go.
 
 <img src="https://raw.githubusercontent.com/kivutar/ludo-assets/master/illustration.png" />
 
-It supports software-rendered and desktop OpenGL libretro cores. Hardware-rendered cores may require a newer OpenGL version than the frontend itself.
+It is able to launch most non GL libretro cores.
 
 It works on OSX, Linux, Linux ARM and Windows. You can download releases [here](https://github.com/libretro/ludo/releases)
 

core/core.go

@@ -35,7 +35,6 @@ var Options *options.Options
 // Call Init before calling other functions of this package.
 func Init(v *video.Video) {
 	vid = v
-	libretro.SetContextCallbacks(v.ContextCallbacks())
 }
 
 // Load loads a libretro core
@@ -52,7 +51,6 @@ func Load(sofile string) error {
 	if err != nil {
 		return err
 	}
-	vid.SetHWRenderContext(nil)
 	state.Core.SetEnvironment(environment)
 	state.Core.Init()
 	state.Core.SetVideoRefresh(vid.Refresh)
@@ -220,15 +218,14 @@ func LoadGame(gamePath string) error {
 		return err
 	}
 
-	if state.Core == nil {
-		return errors.New("no core loaded")
+	// If we're loading a new game on the same core, save the RAM of the previous
+	// game before closing it.
+	if state.GamePath != gamePath {
+		UnloadGame()
 	}
 
-	// Reload the core to fully tear down the previous game and its GL context.
-	if state.CoreRunning {
-		if err := Load(state.CorePath); err != nil {
-			return err
-		}
+	if state.Core == nil {
+		return errors.New("no core loaded")
 	}
 
 	si := state.Core.GetSystemInfo()
@@ -254,7 +251,7 @@ func LoadGame(gamePath string) error {
 
 	ok := state.Core.LoadGame(*gi)
 	if !ok {
-		Unload()
+		state.CoreRunning = false
 		return errors.New("failed to load the game")
 	}
 
@@ -286,56 +283,30 @@ func LoadGame(gamePath string) error {
 	log.Println("[Core]: Game loaded: " + gamePath)
 	savefiles.LoadSRAM()
 
-	if state.Core.HWRenderCallback != nil {
-		if err := vid.ResetHWContext(); err != nil {
-			Unload()
-			return fmt.Errorf("create hardware context: %w", err)
-		}
-	}
-
 	return nil
 }
 
-// Unload closes the game and core before destroying their GL context.
+// Unload unloads a libretro core
 func Unload() {
 	if state.Core != nil {
-		savefiles.SaveSRAM()
-		vid.RunContextDestroy()
-		vid.BeginCore()
-		if state.CoreRunning {
-			state.Core.UnloadGame()
-		}
+		UnloadGame()
 		state.Core.Deinit()
-		vid.EndCore()
-		vid.ResetCoreState()
-		state.GamePath = ""
-		state.CoreRunning = false
 		state.CorePath = ""
 		state.Core = nil
-		vid.SetHWRenderContext(nil)
 		Options = nil
 	}
 }
 
-// Reset resets the game using its hardware context, if any.
-func Reset() {
-	vid.BeginCore()
-	defer vid.EndCore()
-	state.Core.Reset()
-}
-
-// Serialize captures core state with the core's GL context current.
-func Serialize() ([]byte, error) {
-	vid.BeginCore()
-	defer vid.EndCore()
-	return state.Core.Serialize(state.Core.SerializeSize())
-}
-
-// Unserialize restores core state with the core's GL context current.
-func Unserialize(data []byte) error {
-	vid.BeginCore()
-	defer vid.EndCore()
-	return state.Core.Unserialize(data, uint(len(data)))
+// UnloadGame unloads a game.
+func UnloadGame() {
+	if state.CoreRunning {
+		savefiles.SaveSRAM()
+		state.Core.UnloadGame()
+		state.GamePath = ""
+		state.CoreRunning = false
+		vid.ResetPitch()
+		vid.ResetRot()
+	}
 }
 
 // getGameInfo opens a rom and return the libretro.GameInfo needed to launch it

core/core_test.go

@@ -1,10 +1,10 @@
 package core
 
 import (
+	"log"
 	"os"
 	"path/filepath"
 	"reflect"
-	"runtime"
 	"strings"
 	"testing"
 
@@ -15,34 +15,6 @@ import (
 	"github.com/libretro/ludo/video"
 )
 
-var mainThread = make(chan func())
-
-func init() {
-	// GLFW initialization and input setup must run on the main OS thread.
-	runtime.LockOSThread()
-}
-
-func TestMain(m *testing.M) {
-	var code int
-	go func() {
-		code = m.Run()
-		close(mainThread)
-	}()
-	for f := range mainThread {
-		f()
-	}
-	os.Exit(code)
-}
-
-func onMainThread(f func()) {
-	done := make(chan struct{})
-	mainThread <- func() {
-		f()
-		close(done)
-	}
-	<-done
-}
-
 type WindowMock struct{}
 
 func (m WindowMock) GetFramebufferSize() (width, height int)     { return 320, 240 }
@@ -229,21 +201,17 @@ func Test_coreLoadGame(t *testing.T) {
 
 	Init(&video.Video{})
 
-	var initErr error
-	onMainThread(func() { initErr = glfw.Init() })
-	if initErr != nil {
-		t.Fatalf("glfw.Init() error = %v", initErr)
+	if err := glfw.Init(); err != nil {
+		log.Fatalln("failed to initialize glfw")
 	}
-	t.Cleanup(func() { onMainThread(glfw.Terminate) })
+	t.Cleanup(glfw.Terminate)
 
 	if err := Load("testdata/vecx_libretro" + ext); err != nil {
 		t.Fatalf("Load() error = %v", err)
 	}
 
 	var loadGameErr error
-	got := utils.CaptureOutput(func() {
-		onMainThread(func() { loadGameErr = LoadGame("testdata/Polar Rescue (USA).vec") })
-	})
+	got := utils.CaptureOutput(func() { loadGameErr = LoadGame("testdata/Polar Rescue (USA).vec") })
 	if loadGameErr != nil {
 		t.Fatalf("LoadGame() error = %v", loadGameErr)
 	}
@@ -267,6 +235,7 @@ func Test_coreLoadGame(t *testing.T) {
 		}
 	})
 
+	UnloadGame()
 	Unload()
 
 	t.Run("Global state should be cleared by Unload", func(t *testing.T) {
@@ -283,6 +252,7 @@ func Test_coreLoadGame(t *testing.T) {
 }
 
 func Test_coreLoadGameWithoutCore(t *testing.T) {
+	UnloadGame()
 	Unload()
 
 	err := LoadGame("testdata/Polar Rescue (USA).vec")

core/environment.go

@@ -143,30 +143,6 @@ func environment(cmd uint32, data unsafe.Pointer) bool {
 		state.Core.SetFrameTimeCallback(data)
 	case libretro.EnvironmentSetAudioCallback:
 		state.Core.SetAudioCallback(data)
-	case libretro.EnvironmentSetHWRender:
-		hw := libretro.SetHWRenderCallback(
-			data,
-			vid.CurrentFramebuffer,
-			vid.ProcAddress)
-		if (hw.HWContextType != libretro.HWContextOpenGL && hw.HWContextType != libretro.HWContextOpenGLCore) || hw.ContextReset == nil {
-			return false
-		}
-		vid.SetHWRenderContext(hw)
-		if vid != nil && vid.Window != nil && !state.CoreRunning {
-			if err := vid.ReconfigureHWContext(settings.Current.VideoFullscreen); err != nil {
-				vid.SetHWRenderContext(state.Core.HWRenderCallback)
-				log.Printf("[Env]: Could not create HW context %d (%d.%d): %v",
-					hw.HWContextType, hw.VersionMajor, hw.VersionMinor, err)
-				return false
-			}
-			state.MenuContextResetNeeded = true
-		}
-		state.Core.HWRenderCallback = hw
-		log.Println("[Env]: HWContextType:", hw.HWContextType)
-		return true
-	case libretro.EnvironmentSetHWSharedContext:
-		// All HW cores already get an isolated context shared with the frontend.
-		return true
 	case libretro.EnvironmentGetCanDupe:
 		libretro.SetBool(data, true)
 	case libretro.EnvironmentSetPixelFormat:
@@ -175,8 +151,6 @@ func environment(cmd uint32, data unsafe.Pointer) bool {
 		return environmentGetSystemDirectory(data)
 	case libretro.EnvironmentGetSaveDirectory:
 		return environmentGetSaveDirectory(data)
-	case libretro.EnvironmentGetPrefferedHWRender:
-		libretro.SetUint(data, uint(libretro.HWContextOpenGL))
 	case libretro.EnvironmentShutdown:
 		vid.SetShouldClose(true)
 	case libretro.EnvironmentGetCoreOptionsVersion:

go.mod

@@ -7,14 +7,13 @@ require (
 	github.com/fatih/structs v1.1.0
 	github.com/go-gl/gl v0.0.0-20260331235117-4566fea9a276
 	github.com/go-gl/glfw/v3.4/glfw v0.1.0-pre.1
-	github.com/go-gl/mathgl v1.0.0
 	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0
 	github.com/lucasb-eyer/go-colorful v1.4.0
 	github.com/mholt/archives v0.1.5
 	github.com/pelletier/go-toml v1.9.5
 	github.com/tanema/gween v0.0.0-20250522035225-e874ee3ae01a
 	github.com/youpy/go-wav v0.3.2
-	golang.org/x/image v0.41.0
+	golang.org/x/image v0.39.0
 	golang.org/x/mobile v0.0.0-20260410095206-2cfb76559b7b
 )
 
@@ -26,7 +25,7 @@ require (
 	github.com/bodgit/windows v1.0.1 // indirect
 	github.com/dsnet/compress v0.0.2-0.20230904184137-39efe44ab707 // indirect
 	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
-	github.com/klauspost/compress v1.18.7 // indirect
+	github.com/klauspost/compress v1.18.5 // indirect
 	github.com/klauspost/pgzip v1.2.6 // indirect
 	github.com/mikelolasagasti/xz v1.0.1 // indirect
 	github.com/minio/minlz v1.0.1 // indirect
@@ -39,7 +38,7 @@ require (
 	github.com/zaf/g711 v1.4.0 // indirect
 	go4.org v0.0.0-20230225012048-214862532bf5 // indirect
 	golang.org/x/sys v0.43.0 // indirect
-	golang.org/x/text v0.37.0 // indirect
+	golang.org/x/text v0.36.0 // indirect
 )
 
 go 1.25.0

go.sum

@@ -52,8 +52,6 @@ github.com/go-gl/gl v0.0.0-20260331235117-4566fea9a276 h1:IO5P06Pcj9K04d+l4nrf3c
 github.com/go-gl/gl v0.0.0-20260331235117-4566fea9a276/go.mod h1:9YTyiznxEY1fVinfM7RvRcjRHbw2xLBJ3AAGIT0I4Nw=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
-github.com/go-gl/mathgl v1.0.0 h1:t9DznWJlXxxjeeKLIdovCOVJQk/GzDEL7h/h+Ro2B68=
-github.com/go-gl/mathgl v1.0.0/go.mod h1:yhpkQzEiH9yPyxDUGzkmgScbaBVlhC06qodikEM0ZwQ=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
@@ -96,8 +94,8 @@ github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+o
 github.com/kivutar/glfw/v3.4/glfw v0.0.0-20260410202638-4349e4d5a0ee h1:PuDX5smvEEVGSd2s66iGqGtmrSldeBusjnLgIi92Sl4=
 github.com/kivutar/glfw/v3.4/glfw v0.0.0-20260410202638-4349e4d5a0ee/go.mod h1:T5Dn0JwIJOX1euPZ/iT4tq6nFYtmukjcYa7937HuYK8=
 github.com/klauspost/compress v1.4.1/go.mod h1:RyIbtBH6LamlWaDj8nUwkbUhJ87Yi3uG0guNDohfE1A=
-github.com/klauspost/compress v1.18.7 h1:aUyZsS4kH3QTKurYhAOwAHxllVPnOthb3vPfnF1Ehjw=
-github.com/klauspost/compress v1.18.7/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
+github.com/klauspost/compress v1.18.5 h1:/h1gH5Ce+VWNLSWqPzOVn6XBO+vJbCNGvjoaGBFW2IE=
+github.com/klauspost/compress v1.18.5/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
 github.com/klauspost/cpuid v1.2.0/go.mod h1:Pj4uuM528wm8OyEC2QMXAi2YiTZ96dNQPGgoMS4s3ek=
 github.com/klauspost/pgzip v1.2.6 h1:8RXeL5crjEUFnR2/Sn6GJNWtSQ3Dk8pq4CL3jvdDyjU=
 github.com/klauspost/pgzip v1.2.6/go.mod h1:Ch1tH69qFZu15pkjo5kYi6mth2Zzwzt50oCQKQE9RUs=
@@ -177,11 +175,10 @@ golang.org/x/exp v0.0.0-20191129062945-2f5052295587/go.mod h1:2RIsYlXP63K8oxa1u0
 golang.org/x/exp v0.0.0-20191227195350-da58074b4299/go.mod h1:2RIsYlXP63K8oxa1u096TMicItID8zy7Y6sNkU49FU4=
 golang.org/x/exp v0.0.0-20200207192155-f17229e696bd/go.mod h1:J/WKrq2StrnmMY6+EHIKF9dgMWnmCNThgcyBT1FY9mM=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
-golang.org/x/image v0.0.0-20190321063152-3fc05d484e9f/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
 golang.org/x/image v0.0.0-20190802002840-cff245a6509b/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
 golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
-golang.org/x/image v0.41.0 h1:8wS72eGJMJaBxK6okTzd4WaXumUlTVlb753MlsSvTCo=
-golang.org/x/image v0.41.0/go.mod h1:uIc348UZMSvS5Z65CVZ7iDPaNobNFEPeJ4kbqTOszmA=
+golang.org/x/image v0.39.0 h1:skVYidAEVKgn8lZ602XO75asgXBgLj9G/FE3RbuPFww=
+golang.org/x/image v0.39.0/go.mod h1:sIbmppfU+xFLPIG0FoVUTvyBMmgng1/XAMhQ2ft0hpA=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
 golang.org/x/lint v0.0.0-20190227174305-5b3e6a55c961/go.mod h1:wehouNa3lNwaWXcvxsM5YxQ5yQlVC4a0KAMCusXpPoU=
 golang.org/x/lint v0.0.0-20190301231843-5614ed5bae6f/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
@@ -259,8 +256,8 @@ golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.37.0 h1:Cqjiwd9eSg8e0QAkyCaQTNHFIIzWtidPahFWR83rTrc=
-golang.org/x/text v0.37.0/go.mod h1:a5sjxXGs9hsn/AJVwuElvCAo9v8QYLzvavO5z2PiM38=
+golang.org/x/text v0.36.0 h1:JfKh3XmcRPqZPKevfXVpI1wXPTqbkE5f7JA92a55Yxg=
+golang.org/x/text v0.36.0/go.mod h1:NIdBknypM8iqVmPiuco0Dh6P5Jcdk8lJL0CUebqK164=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

libretro/cfuncs.go

@@ -6,36 +6,121 @@ package libretro
 #include <stdarg.h>
 #include <stdio.h>
 #include <pthread.h>
-#include <stdint.h>
 
+#ifdef __APPLE__
+#include <mach/semaphore.h>
+#include <mach/task.h>
+#include <mach/mach_init.h>
+#define SEM_T semaphore_t
+#define SEM_INIT(x) semaphore_create(mach_task_self(), &x, SYNC_POLICY_FIFO, 0);
+#define SEM_POST(x) semaphore_signal(x)
+#define SEM_WAIT(x) semaphore_wait(x)
+#else
+#include <semaphore.h>
+#define SEM_T sem_t
+#define SEM_INIT(x) sem_init(&x, 0, 0)
+#define SEM_POST(x) sem_post(&x)
+#define SEM_WAIT(x) sem_wait(&x)
+#endif
+
+#if 0
+#define print_sema(...) (printf(__VA_ARGS__))
+#else
+#define print_sema(...) do {} while (0)
+#endif
+
+enum {
+	CMD_F,
+	CMD_SERIALIZE,
+};
+
+struct thread_cmd_t {
+	int   cmd;
+	void* f;
+	void* arg1;
+	void* arg2;
+	void* arg3;
+	void* arg4;
+	void* res;
+};
+
+struct thread_cmd_t s_job;
 static pthread_t s_thread;
-static uintptr_t s_current_framebuffer = 0;
+static SEM_T s_sem_do;
+static SEM_T s_sem_done;
+static bool s_use_thread = false;
 
-// Go can track libco's alternate callback stacks only on a C-created thread.
-static void *emu_thread_loop(void *unused) {
-	void coreThreadLoop();
-	coreThreadLoop();
-	return NULL;
+void* emu_thread_loop(void *a0) {
+	print_sema("begin thread\n");
+
+	SEM_POST(s_sem_done);
+
+	print_sema("signal thread\n");
+
+	while (1) {
+		print_sema("wait do\n");
+		SEM_WAIT(s_sem_do);
+
+		print_sema("do\n");
+		switch (s_job.cmd) {
+		case CMD_F:
+			((void (*)(void))s_job.f)();
+			break;
+		case CMD_SERIALIZE: {
+			bool res = ((bool (*)(void*, size_t))s_job.f)(s_job.arg1, *(size_t*)s_job.arg2);
+			*(bool*)s_job.res = res;
+			break;
+		}
+		default:
+			break;
+		}
+
+		print_sema("signal done\n");
+		SEM_POST(s_sem_done);
+	}
 }
 
-int cothread_init() {
-	return pthread_create(&s_thread, NULL, emu_thread_loop, NULL);
+void thread_sync() {
+	// Fire the job
+	print_sema("signal do\n");
+	SEM_POST(s_sem_do);
+
+	// Wait the result
+	print_sema("wait done\n");
+	SEM_WAIT(s_sem_done);
+
+	print_sema("done\n");
 }
 
-void cothread_deinit() {
-	pthread_join(s_thread, NULL);
+void run_wrapper(void *f) {
+	if (s_use_thread) {
+		s_job.cmd = CMD_F;
+		s_job.f = f;
+		thread_sync();
+	} else {
+		((void (*)(void))f)();
+	}
 }
 
-bool cothread_is_current() {
-	return pthread_equal(pthread_self(), s_thread);
+void cothread_init() {
+	s_use_thread = true;
+
+	SEM_INIT(s_sem_do);
+	SEM_INIT(s_sem_done);
+
+	print_sema("create thread\n");
+	pthread_create(&s_thread, NULL, emu_thread_loop, NULL);
+
+	print_sema("wait thread\n");
+	SEM_WAIT(s_sem_done);
 }
 
 void bridge_retro_init(void *f) {
-	((void (*)(void))f)();
+	run_wrapper(f);
 }
 
 void bridge_retro_deinit(void *f) {
-	((void (*)(void))f)();
+	run_wrapper(f);
 }
 
 unsigned bridge_retro_api_version(void *f) {
@@ -46,14 +131,6 @@ void bridge_retro_frame_time_callback(retro_frame_time_callback_t f, retro_usec_
 	f(usec);
 }
 
-void bridge_retro_hw_context_reset(retro_hw_context_reset_t f) {
-	f();
-}
-
-void bridge_retro_hw_context_destroy(retro_hw_context_reset_t f) {
-	f();
-}
-
 void bridge_retro_audio_callback(retro_audio_callback_t f) {
 	f();
 }
@@ -75,7 +152,7 @@ void bridge_retro_set_environment(void *f, void *callback) {
 }
 
 void bridge_retro_set_video_refresh(void *f, void *callback) {
-	((void (*)(retro_video_refresh_t))f)((retro_video_refresh_t)callback);
+	((bool (*)(retro_video_refresh_t))f)((retro_video_refresh_t)callback);
 }
 
 void bridge_retro_set_controller_port_device(void *f, unsigned port, unsigned device) {
@@ -83,23 +160,23 @@ void bridge_retro_set_controller_port_device(void *f, unsigned port, unsigned de
 }
 
 void bridge_retro_set_input_poll(void *f, void *callback) {
-	((void (*)(retro_input_poll_t))f)((retro_input_poll_t)callback);
+	((bool (*)(retro_input_poll_t))f)((retro_input_poll_t)callback);
 }
 
 void bridge_retro_set_input_state(void *f, void *callback) {
-	((void (*)(retro_input_state_t))f)((retro_input_state_t)callback);
+	((bool (*)(retro_input_state_t))f)((retro_input_state_t)callback);
 }
 
 void bridge_retro_set_audio_sample(void *f, void *callback) {
-	((void (*)(retro_audio_sample_t))f)((retro_audio_sample_t)callback);
+	((bool (*)(retro_audio_sample_t))f)((retro_audio_sample_t)callback);
 }
 
 void bridge_retro_set_audio_sample_batch(void *f, void *callback) {
-	((void (*)(retro_audio_sample_batch_t))f)((retro_audio_sample_batch_t)callback);
+	((bool (*)(retro_audio_sample_batch_t))f)((retro_audio_sample_batch_t)callback);
 }
 
 bool bridge_retro_load_game(void *f, struct retro_game_info *gi) {
-  return ((bool (*)(const struct retro_game_info *))f)(gi);
+  return ((bool (*)(struct retro_game_info *))f)(gi);
 }
 
 size_t bridge_retro_serialize_size(void *f) {
@@ -107,23 +184,49 @@ size_t bridge_retro_serialize_size(void *f) {
 }
 
 bool bridge_retro_serialize(void *f, void *data, size_t size) {
-	return ((bool (*)(void*, size_t))f)(data, size);
+	if (s_use_thread) {
+		bool res;
+		s_job.cmd = CMD_SERIALIZE;
+		s_job.f = f;
+		s_job.arg1 = data;
+		s_job.arg2 = &size;
+		s_job.res  = &res;
+
+		thread_sync();
+
+		return s_job.res;
+	} else {
+		return ((bool (*)(void*, size_t))f)(data, size);
+	}
 }
 
 bool bridge_retro_unserialize(void *f, void *data, size_t size) {
-	return ((bool (*)(const void*, size_t))f)(data, size);
+	if (s_use_thread) {
+		bool res;
+		s_job.cmd = CMD_SERIALIZE; // Same command format for both serialize & unserialize
+		s_job.f = f;
+		s_job.arg1 = data;
+		s_job.arg2 = &size;
+		s_job.res  = &res;
+
+		thread_sync();
+
+		return s_job.res;
+	} else {
+		return ((bool (*)(void*, size_t))f)(data, size);
+	}
 }
 
 void bridge_retro_unload_game(void *f) {
-	((void (*)(void))f)();
+	run_wrapper(f);
 }
 
 void bridge_retro_run(void *f) {
-	((void (*)(void))f)();
+	run_wrapper(f);
 }
 
 void bridge_retro_reset(void *f) {
-	((void (*)(void))f)();
+	run_wrapper(f);
 }
 
 size_t bridge_retro_get_memory_size(void *f, unsigned id) {
@@ -200,18 +303,5 @@ int64_t coreGetTimeUsec_cgo() {
 	return coreGetTimeUsec();
 }
 
-uintptr_t coreGetCurrentFramebuffer_cgo() {
-	return s_current_framebuffer;
-}
-
-void coreSetCurrentFramebuffer_cgo(uintptr_t fb) {
-	s_current_framebuffer = fb;
-}
-
-uintptr_t coreGetProcAddress_cgo(const char *sym) {
-	uintptr_t coreGetProcAddress(const char *sym);
-	return coreGetProcAddress(sym);
-}
-
 */
 import "C"

libretro/libretro.go

@@ -14,9 +14,7 @@ package libretro
 #include <stdio.h>
 #include <string.h>
 
-int cothread_init();
-void cothread_deinit();
-bool cothread_is_current();
+void cothread_init();
 
 void bridge_retro_init(void *f);
 void bridge_retro_deinit(void *f);
@@ -38,8 +36,6 @@ void bridge_retro_unload_game(void *f);
 void bridge_retro_run(void *f);
 void bridge_retro_reset(void *f);
 void bridge_retro_frame_time_callback(retro_frame_time_callback_t f, retro_usec_t usec);
-void bridge_retro_hw_context_reset(retro_hw_context_reset_t f);
-void bridge_retro_hw_context_destroy(retro_hw_context_reset_t f);
 void bridge_retro_audio_callback(retro_audio_callback_t f);
 void bridge_retro_audio_set_state(retro_audio_set_state_callback_t f, bool state);
 size_t bridge_retro_get_memory_size(void *f, unsigned id);
@@ -58,15 +54,10 @@ size_t coreAudioSampleBatch_cgo(const int16_t *data, size_t frames);
 int16_t coreInputState_cgo(unsigned port, unsigned device, unsigned index, unsigned id);
 void coreLog_cgo(enum retro_log_level level, const char *msg);
 int64_t coreGetTimeUsec_cgo();
-uintptr_t coreGetCurrentFramebuffer_cgo();
-void coreSetCurrentFramebuffer_cgo(uintptr_t fb);
-uintptr_t coreGetProcAddress_cgo(const char *sym);
 */
 import "C"
 import (
 	"errors"
-	"fmt"
-	"runtime"
 	"strings"
 	"unsafe"
 )
@@ -228,20 +219,6 @@ type FrameTimeCallback struct {
 	Reference int64
 }
 
-// HWRenderCallback sets an interface to let a libretro core render with
-// hardware acceleration.
-type HWRenderCallback struct {
-	HWContextType              uint32
-	ContextReset               func()
-	Depth                      bool
-	Stencil                    bool
-	BottomLeftOrigin           bool
-	VersionMajor, VersionMinor uint
-	CacheContext               bool
-	ContextDestroy             func()
-	DebugContext               bool
-}
-
 // AudioCallback stores the audio callback itself and the SetState callback
 type AudioCallback struct {
 	Callback func()
@@ -435,35 +412,15 @@ const (
 	MemoryVideoRAM  = uint32(C.RETRO_MEMORY_VIDEO_RAM)
 )
 
-// Hardware contexts
-const (
-	HWContextNone            = uint32(C.RETRO_HW_CONTEXT_NONE)
-	HWContextOpenGL          = uint32(C.RETRO_HW_CONTEXT_OPENGL)
-	HWContextOpenGLES2       = uint32(C.RETRO_HW_CONTEXT_OPENGLES2)
-	HWContextOpenGLCore      = uint32(C.RETRO_HW_CONTEXT_OPENGL_CORE)
-	HWContextOpenGLES3       = uint32(C.RETRO_HW_CONTEXT_OPENGLES3)
-	HWContextOpenGLESVersion = uint32(C.RETRO_HW_CONTEXT_OPENGLES_VERSION)
-	HWContextVulkan          = uint32(C.RETRO_HW_CONTEXT_VULKAN)
-	HWContextDummy           = uint32(C.RETRO_HW_CONTEXT_DUMMY)
-)
-
-// Pass this to retro_video_refresh_t if rendering to hardware.
-// Passing NULL to retro_video_refresh_t is still a frame dupe as normal.
-var (
-	HWFrameBufferValid = unsafe.Pointer(C.RETRO_HW_FRAME_BUFFER_VALID)
-)
-
 type (
-	environmentFunc           func(uint32, unsafe.Pointer) bool
-	videoRefreshFunc          func(unsafe.Pointer, int32, int32, int32)
-	audioSampleFunc           func(int16, int16)
-	audioSampleBatchFunc      func([]byte, int32) int32
-	inputPollFunc             func()
-	inputStateFunc            func(uint, uint32, uint, uint) int16
-	logFunc                   func(uint32, string)
-	getTimeUsecFunc           func() int64
-	getCurrentFramebufferFunc func() uintptr
-	getProcAddressFunc        func(string) uintptr
+	environmentFunc      func(uint32, unsafe.Pointer) bool
+	videoRefreshFunc     func(unsafe.Pointer, int32, int32, int32)
+	audioSampleFunc      func(int16, int16)
+	audioSampleBatchFunc func([]byte, int32) int32
+	inputPollFunc        func()
+	inputStateFunc       func(uint, uint32, uint, uint) int16
+	logFunc              func(uint32, string)
+	getTimeUsecFunc      func() int64
 )
 
 var (
@@ -475,84 +432,8 @@ var (
 	inputState       inputStateFunc
 	log              logFunc
 	getTimeUsec      getTimeUsecFunc
-	getProcAddress   getProcAddressFunc
-	releaseContext   func()
-	acquireContext   func()
-	coreCalls        chan func()
-	frontendCalls    chan func()
 )
 
-// SetContextCallbacks hands the current graphics context between the calling
-// thread and the native core thread. Calls remain synchronous.
-func SetContextCallbacks(release, acquire func()) {
-	releaseContext, acquireContext = release, acquire
-}
-
-func coreReleaseContext() {
-	if releaseContext != nil {
-		releaseContext()
-	}
-}
-
-func coreAcquireContext() {
-	if acquireContext != nil {
-		acquireContext()
-	}
-}
-
-//export coreThreadLoop
-func coreThreadLoop() {
-	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
-	for call := range coreCalls {
-		call()
-	}
-}
-
-// Calls are synchronous, but must service callbacks on the waiting thread.
-// Pumping both directions also permits a callback to make a nested core call.
-func threadCall(calls, callbacks chan func(), f func()) {
-	coreReleaseContext()
-	done := make(chan struct{})
-	calls <- func() {
-		coreAcquireContext()
-		f()
-		coreReleaseContext()
-		close(done)
-	}
-	for {
-		select {
-		case callback := <-callbacks:
-			callback()
-		case <-done:
-			coreAcquireContext()
-			return
-		}
-	}
-}
-
-// The frontend calls from its locked OS thread; core callbacks can reenter here.
-func coreCall(f func()) {
-	if coreCalls == nil || bool(C.cothread_is_current()) {
-		f()
-		return
-	}
-	threadCall(coreCalls, frontendCalls, f)
-}
-
-func coreResult[T any](f func() T) (result T) {
-	coreCall(func() { result = f() })
-	return
-}
-
-func frontendCall(f func()) {
-	if coreCalls == nil || !bool(C.cothread_is_current()) {
-		f()
-		return
-	}
-	threadCall(frontendCalls, coreCalls, f)
-}
-
 // Load dynamically loads a libretro core at the given path and returns a Core instance
 func Load(sofile string) (*Core, error) {
 	core := Core{}
@@ -563,12 +444,7 @@ func Load(sofile string) (*Core, error) {
 		return nil, err
 	}
 
-	coreCalls, frontendCalls = make(chan func()), make(chan func())
-	if err := C.cothread_init(); err != 0 {
-		coreCalls, frontendCalls = nil, nil
-		DlClose(core.handle)
-		return nil, fmt.Errorf("start core thread: %s", C.GoString(C.strerror(err)))
-	}
+	C.cothread_init()
 
 	core.symRetroInit = DlSym(core.handle, "retro_init")
 	core.symRetroDeinit = DlSym(core.handle, "retro_deinit")
@@ -597,21 +473,18 @@ func Load(sofile string) (*Core, error) {
 
 // Init takes care of the library global initialization
 func (core *Core) Init() {
-	coreCall(func() { C.bridge_retro_init(core.symRetroInit) })
+	C.bridge_retro_init(core.symRetroInit)
 }
 
 // APIVersion returns the RETRO_API_VERSION.
 // Used to validate ABI compatibility when the API is revised.
 func (core *Core) APIVersion() uint {
-	return coreResult(func() uint { return uint(C.bridge_retro_api_version(core.symRetroAPIVersion)) })
+	return uint(C.bridge_retro_api_version(core.symRetroAPIVersion))
 }
 
 // Deinit takes care of the library global deinitialization
 func (core *Core) Deinit() {
-	coreCall(func() { C.bridge_retro_deinit(core.symRetroDeinit) })
-	close(coreCalls)
-	C.cothread_deinit()
-	coreCalls, frontendCalls = nil, nil
+	C.bridge_retro_deinit(core.symRetroDeinit)
 	DlClose(core.handle)
 	core.MemoryMap = nil
 	environment = nil
@@ -622,7 +495,6 @@ func (core *Core) Deinit() {
 	inputState = nil
 	log = nil
 	getTimeUsec = nil
-	getProcAddress = nil
 }
 
 // Run runs the game for one video frame.
@@ -632,12 +504,12 @@ func (core *Core) Deinit() {
 // a frame if GET_CAN_DUPE returns true.
 // In this case, the video callback can take a NULL argument for data.
 func (core *Core) Run() {
-	coreCall(func() { C.bridge_retro_run(core.symRetroRun) })
+	C.bridge_retro_run(core.symRetroRun)
 }
 
 // Reset resets the current game.
 func (core *Core) Reset() {
-	coreCall(func() { C.bridge_retro_reset(core.symRetroReset) })
+	C.bridge_retro_reset(core.symRetroReset)
 }
 
 // GetSystemInfo returns statically known system info. Pointers provided in *info
@@ -645,7 +517,7 @@ func (core *Core) Reset() {
 // Can be called at any time, even before retro_init().
 func (core *Core) GetSystemInfo() SystemInfo {
 	rsi := C.struct_retro_system_info{}
-	coreCall(func() { C.bridge_retro_get_system_info(core.symRetroGetSystemInfo, &rsi) })
+	C.bridge_retro_get_system_info(core.symRetroGetSystemInfo, &rsi)
 	return SystemInfo{
 		LibraryName:     C.GoString(rsi.library_name),
 		LibraryVersion:  C.GoString(rsi.library_version),
@@ -663,7 +535,7 @@ func (core *Core) GetSystemInfo() SystemInfo {
 // desire a particular aspect ratio.
 func (core *Core) GetSystemAVInfo() SystemAVInfo {
 	avi := C.struct_retro_system_av_info{}
-	coreCall(func() { C.bridge_retro_get_system_av_info(core.symRetroGetSystemAVInfo, &avi) })
+	C.bridge_retro_get_system_av_info(core.symRetroGetSystemAVInfo, &avi)
 	return SystemAVInfo{
 		Geometry: GameGeometry{
 			AspectRatio: float64(avi.geometry.aspect_ratio),
@@ -685,7 +557,7 @@ func (core *Core) LoadGame(gi GameInfo) bool {
 	rgi.path = C.CString(gi.Path)
 	rgi.size = C.size_t(gi.Size)
 	rgi.data = gi.Data
-	return coreResult(func() bool { return bool(C.bridge_retro_load_game(core.symRetroLoadGame, &rgi)) })
+	return bool(C.bridge_retro_load_game(core.symRetroLoadGame, &rgi))
 }
 
 // SerializeSize returns the amount of data the implementation requires to serialize
@@ -694,18 +566,18 @@ func (core *Core) LoadGame(gi GameInfo) bool {
 // returned size is never allowed to be larger than a previous returned
 // value, to ensure that the frontend can allocate a save state buffer once.
 func (core *Core) SerializeSize() uint {
-	return coreResult(func() uint { return uint(C.bridge_retro_serialize_size(core.symRetroSerializeSize)) })
+	return uint(C.bridge_retro_serialize_size(core.symRetroSerializeSize))
 }
 
 // Serialize serializes internal state and returns the state as a byte slice.
 func (core *Core) Serialize(size uint) ([]byte, error) {
 	data := C.malloc(C.size_t(size))
-	defer C.free(data)
-	ok := coreResult(func() bool { return bool(C.bridge_retro_serialize(core.symRetroSerialize, data, C.size_t(size))) })
+	ok := bool(C.bridge_retro_serialize(core.symRetroSerialize, data, C.size_t(size)))
 	if !ok {
 		return nil, errors.New("retro_serialize failed")
 	}
 	bytes := C.GoBytes(data, C.int(size))
+	C.free(data)
 	return bytes, nil
 }
 
@@ -717,9 +589,7 @@ func (core *Core) Unserialize(bytes []byte, size uint) error {
 	if uint(len(bytes)) > size {
 		size = uint(len(bytes))
 	}
-	ok := coreResult(func() bool {
-		return bool(C.bridge_retro_unserialize(core.symRetroUnserialize, unsafe.Pointer(&bytes[0]), C.size_t(size)))
-	})
+	ok := bool(C.bridge_retro_unserialize(core.symRetroUnserialize, unsafe.Pointer(&bytes[0]), C.size_t(size)))
 	if !ok {
 		return errors.New("retro_unserialize failed")
 	}
@@ -728,51 +598,49 @@ func (core *Core) Unserialize(bytes []byte, size uint) error {
 
 // UnloadGame unloads a currently loaded game
 func (core *Core) UnloadGame() {
-	coreCall(func() { C.bridge_retro_unload_game(core.symRetroUnloadGame) })
+	C.bridge_retro_unload_game(core.symRetroUnloadGame)
 }
 
 // SetEnvironment sets the environment callback.
 // Must be called before Init
 func (core *Core) SetEnvironment(f environmentFunc) {
 	environment = f
-	coreCall(func() { C.bridge_retro_set_environment(core.symRetroSetEnvironment, C.coreEnvironment_cgo) })
+	C.bridge_retro_set_environment(core.symRetroSetEnvironment, C.coreEnvironment_cgo)
 }
 
 // SetVideoRefresh sets the video refresh callback.
 // Must be set before the first Run call
 func (core *Core) SetVideoRefresh(f videoRefreshFunc) {
 	videoRefresh = f
-	coreCall(func() { C.bridge_retro_set_video_refresh(core.symRetroSetVideoRefresh, C.coreVideoRefresh_cgo) })
+	C.bridge_retro_set_video_refresh(core.symRetroSetVideoRefresh, C.coreVideoRefresh_cgo)
 }
 
 // SetAudioSample sets the audio sample callback.
 // Must be set before the first Run call
 func (core *Core) SetAudioSample(f audioSampleFunc) {
 	audioSample = f
-	coreCall(func() { C.bridge_retro_set_audio_sample(core.symRetroSetAudioSample, C.coreAudioSample_cgo) })
+	C.bridge_retro_set_audio_sample(core.symRetroSetAudioSample, C.coreAudioSample_cgo)
 }
 
 // SetAudioSampleBatch sets the audio sample batch callback.
 // Must be set before the first Run call
 func (core *Core) SetAudioSampleBatch(f audioSampleBatchFunc) {
 	audioSampleBatch = f
-	coreCall(func() {
-		C.bridge_retro_set_audio_sample_batch(core.symRetroSetAudioSampleBatch, C.coreAudioSampleBatch_cgo)
-	})
+	C.bridge_retro_set_audio_sample_batch(core.symRetroSetAudioSampleBatch, C.coreAudioSampleBatch_cgo)
 }
 
 // SetInputPoll sets the input poll callback.
 // Must be set before the first Run call
 func (core *Core) SetInputPoll(f inputPollFunc) {
 	inputPoll = f
-	coreCall(func() { C.bridge_retro_set_input_poll(core.symRetroSetInputPoll, C.coreInputPoll_cgo) })
+	C.bridge_retro_set_input_poll(core.symRetroSetInputPoll, C.coreInputPoll_cgo)
 }
 
 // SetInputState sets the input state callback.
 // Must be set before the first Run call
 func (core *Core) SetInputState(f inputStateFunc) {
 	inputState = f
-	coreCall(func() { C.bridge_retro_set_input_state(core.symRetroSetInputState, C.coreInputState_cgo) })
+	C.bridge_retro_set_input_state(core.symRetroSetInputState, C.coreInputState_cgo)
 }
 
 // BindLogCallback binds f to the log callback
@@ -791,9 +659,7 @@ func (core *Core) BindPerfCallback(data unsafe.Pointer, f getTimeUsecFunc) {
 
 // SetControllerPortDevice sets the device type attached to a controller port
 func (core *Core) SetControllerPortDevice(port uint, device uint32) {
-	coreCall(func() {
-		C.bridge_retro_set_controller_port_device(core.symRetroSetControllerPortDevice, C.unsigned(port), C.unsigned(device))
-	})
+	C.bridge_retro_set_controller_port_device(core.symRetroSetControllerPortDevice, C.unsigned(port), C.unsigned(device))
 }
 
 //export coreEnvironment
@@ -801,12 +667,6 @@ func coreEnvironment(cmd C.unsigned, data unsafe.Pointer) bool {
 	if environment == nil {
 		return false
 	}
-	// Only window operations need the frontend thread. Routine queries stay here.
-	if cmd == C.RETRO_ENVIRONMENT_SET_HW_RENDER || cmd == C.RETRO_ENVIRONMENT_SHUTDOWN {
-		var result bool
-		frontendCall(func() { result = environment(uint32(cmd), data) })
-		return result
-	}
 	return environment(uint32(cmd), data)
 }
 
@@ -831,12 +691,6 @@ func coreInputState(port C.unsigned, device C.unsigned, index C.unsigned, id C.u
 	if inputState == nil {
 		return 0
 	}
-	// Mouse state is queried through GLFW rather than the polled input snapshot.
-	if device == C.RETRO_DEVICE_MOUSE {
-		var result C.int16_t
-		frontendCall(func() { result = C.int16_t(inputState(uint(port), uint32(device), uint(index), uint(id))) })
-		return result
-	}
 	return C.int16_t(inputState(uint(port), uint32(device), uint(index), uint(id)))
 }
 
@@ -872,16 +726,6 @@ func coreGetTimeUsec() C.uint64_t {
 	return C.uint64_t(getTimeUsec())
 }
 
-//export coreGetProcAddress
-func coreGetProcAddress(sym *C.char) C.uintptr_t {
-	return C.uintptr_t(getProcAddress(C.GoString(sym)))
-}
-
-// SetCurrentFramebufferValue updates the C-side framebuffer callback target
-func SetCurrentFramebufferValue(fb uintptr) {
-	C.coreSetCurrentFramebuffer_cgo(C.uintptr_t(fb))
-}
-
 // SetData is a setter for the data of a GameInfo type
 func (gi *GameInfo) SetData(bytes []byte) {
 	cstr := C.CString(string(bytes))
@@ -1039,58 +883,20 @@ func (core *Core) SetFrameTimeCallback(data unsafe.Pointer) {
 	ftc := &FrameTimeCallback{}
 	ftc.Reference = int64(c.reference)
 	ftc.Callback = func(usec int64) {
-		coreCall(func() { C.bridge_retro_frame_time_callback(c.callback, C.retro_usec_t(usec)) })
+		C.bridge_retro_frame_time_callback(c.callback, C.retro_usec_t(usec))
 	}
 	core.FrameTimeCallback = ftc
 }
 
-// SetHWRenderCallback is an environment callback helper to set the HWRenderCallback
-func SetHWRenderCallback(
-	data unsafe.Pointer,
-	currentFramebuffer getCurrentFramebufferFunc,
-	procAddress getProcAddressFunc,
-) *HWRenderCallback {
-	c := (*C.struct_retro_hw_render_callback)(data)
-	hwrc := HWRenderCallback{}
-	hwrc.HWContextType = uint32(c.context_type)
-
-	getProcAddress = procAddress
-	SetCurrentFramebufferValue(currentFramebuffer())
-	c.get_current_framebuffer = (C.retro_hw_get_current_framebuffer_t)(C.coreGetCurrentFramebuffer_cgo)
-	c.get_proc_address = (C.retro_hw_get_proc_address_t)(C.coreGetProcAddress_cgo)
-
-	// The request may be stack-allocated by the core. Keep callback values, not c.
-	reset, destroy := c.context_reset, c.context_destroy
-	if reset != nil {
-		hwrc.ContextReset = func() {
-			coreCall(func() { C.bridge_retro_hw_context_reset(reset) })
-		}
-	}
-
-	hwrc.Depth = bool(c.depth)
-	hwrc.Stencil = bool(c.stencil)
-	hwrc.BottomLeftOrigin = bool(c.bottom_left_origin)
-	hwrc.VersionMajor = uint(c.version_major)
-	hwrc.VersionMinor = uint(c.version_minor)
-	hwrc.CacheContext = bool(c.cache_context)
-	if destroy != nil {
-		hwrc.ContextDestroy = func() {
-			coreCall(func() { C.bridge_retro_hw_context_destroy(destroy) })
-		}
-	}
-	hwrc.DebugContext = bool(c.debug_context)
-	return &hwrc
-}
-
 // SetAudioCallback is an environment callback helper to set the AudioCallback
 func (core *Core) SetAudioCallback(data unsafe.Pointer) {
 	c := *(*C.struct_retro_audio_callback)(data)
 	auc := &AudioCallback{}
 	auc.Callback = func() {
-		coreCall(func() { C.bridge_retro_audio_callback(c.callback) })
+		C.bridge_retro_audio_callback(c.callback)
 	}
 	auc.SetState = func(state bool) {
-		coreCall(func() { C.bridge_retro_audio_set_state(c.set_state, C.bool(state)) })
+		C.bridge_retro_audio_set_state(c.set_state, C.bool(state))
 	}
 	core.AudioCallback = auc
 }
@@ -1098,15 +904,13 @@ func (core *Core) SetAudioCallback(data unsafe.Pointer) {
 // GetMemorySize returns the size of a region of the memory.
 // See memory constants.
 func (core *Core) GetMemorySize(id uint32) uint {
-	return coreResult(func() uint { return uint(C.bridge_retro_get_memory_size(core.symRetroGetMemorySize, C.unsigned(id))) })
+	return uint(C.bridge_retro_get_memory_size(core.symRetroGetMemorySize, C.unsigned(id)))
 }
 
 // GetMemoryData returns the size of a region of the memory.
 // See memory constants.
 func (core *Core) GetMemoryData(id uint32) unsafe.Pointer {
-	return coreResult(func() unsafe.Pointer {
-		return C.bridge_retro_get_memory_data(core.symRetroGetMemoryData, C.unsigned(id))
-	})
+	return C.bridge_retro_get_memory_data(core.symRetroGetMemoryData, C.unsigned(id))
 }
 
 // DiskControlCallback is an interface which frontend can use to eject and insert disk images
@@ -1126,19 +930,19 @@ func (core *Core) SetDiskControlCallback(data unsafe.Pointer) {
 	c := *(*C.struct_retro_disk_control_callback)(data)
 	dcc := &DiskControlCallback{}
 	dcc.SetEjectState = func(state bool) {
-		coreCall(func() { C.bridge_retro_set_eject_state(c.set_eject_state, C.bool(state)) })
+		C.bridge_retro_set_eject_state(c.set_eject_state, C.bool(state))
 	}
 	dcc.GetEjectState = func() bool {
-		return coreResult(func() bool { return bool(C.bridge_retro_get_eject_state(c.get_eject_state)) })
+		return bool(C.bridge_retro_get_eject_state(c.get_eject_state))
 	}
 	dcc.GetImageIndex = func() uint {
-		return coreResult(func() uint { return uint(C.bridge_retro_get_image_index(c.get_image_index)) })
+		return uint(C.bridge_retro_get_image_index(c.get_image_index))
 	}
 	dcc.SetImageIndex = func(index uint) {
-		coreCall(func() { C.bridge_retro_set_image_index(c.set_image_index, C.uint(index)) })
+		C.bridge_retro_set_image_index(c.set_image_index, C.uint(index))
 	}
 	dcc.GetNumImages = func() uint {
-		return coreResult(func() uint { return uint(C.bridge_retro_get_num_images(c.get_num_images)) })
+		return uint(C.bridge_retro_get_num_images(c.get_num_images))
 	}
 	core.DiskControlCallback = dcc
 }

libretro/libretro_core.go

@@ -31,7 +31,6 @@ type Core struct {
 	AudioCallback       *AudioCallback
 	FrameTimeCallback   *FrameTimeCallback
 	DiskControlCallback *DiskControlCallback
-	HWRenderCallback    *HWRenderCallback
 
 	MemoryMap []MemoryDescriptor
 }

libretro/libretro_notwindows.go

@@ -28,8 +28,8 @@ func DlOpen(path string) (DlHandle, error) {
 	defer C.free(unsafe.Pointer(cpath))
 
 	h := C.dlopen(cpath, C.RTLD_LAZY|C.RTLD_GLOBAL)
-	if h == nil {
-		cerr := C.dlerror()
+	cerr := C.dlerror()
+	if h == nil || cerr != nil {
 		err := C.GoString(cerr)
 		return nil, errors.New(err)
 	}

main.go

@@ -30,22 +30,6 @@ func init() {
 
 var frame = 0
 
-func fulfillPendingScreenshot(vid *video.Video) {
-	if state.PendingScreenshotName == "" {
-		return
-	}
-
-	name := state.PendingScreenshotName
-	done := state.PendingScreenshotDone
-	state.PendingScreenshotName = ""
-	state.PendingScreenshotDone = nil
-
-	err := vid.TakeScreenshotInFrontendFrame(name)
-	if done != nil {
-		done(err)
-	}
-}
-
 func runLoop(vid *video.Video, m *menu.Menu) {
 	var currTime time.Time
 	prevTime := time.Now()
@@ -55,19 +39,11 @@ func runLoop(vid *video.Video, m *menu.Menu) {
 		glfw.PollEvents()
 		m.ProcessHotkeys()
 		ntf.Process(dt)
+		vid.ResizeViewport()
 		m.UpdatePalette()
 		input.Poll()
-		menuActive := state.MenuActive
-		if menuActive {
-			m.Update(dt)
-		}
-		if state.MenuContextResetNeeded {
-			m.ContextReset()
-			state.MenuContextResetNeeded = false
-		}
-		if !menuActive {
+		if !state.MenuActive {
 			if state.CoreRunning {
-				vid.BeginCore()
 				state.Core.Run()
 				if state.Core.FrameTimeCallback != nil {
 					state.Core.FrameTimeCallback.Callback(state.Core.FrameTimeCallback.Reference)
@@ -75,23 +51,18 @@ func runLoop(vid *video.Video, m *menu.Menu) {
 				if state.Core.AudioCallback != nil {
 					state.Core.AudioCallback.Callback()
 				}
-				vid.EndCore()
 			}
-			vid.BeginFrontendFrame()
 			vid.Render()
-			vid.CachePresentedFrame()
-			m.RenderNotifications()
 			frame++
 			if frame%600 == 0 { // save sram about every 10 sec
 				savefiles.SaveSRAM()
 			}
 		} else {
-			vid.BeginFrontendFrame()
-			vid.RenderPresentedFrame()
-			fulfillPendingScreenshot(vid)
+			m.Update(dt)
+			vid.Render()
 			m.Render(dt)
-			m.RenderNotifications()
 		}
+		m.RenderNotifications()
 		if state.FastForward {
 			glfw.SwapInterval(0)
 		} else {
@@ -157,14 +128,18 @@ func main() {
 	input.Init(vid)
 
 	if len(state.CorePath) > 0 {
-		if err := core.Load(state.CorePath); err != nil {
-			ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
-		} else if len(gamePath) > 0 {
-			if err := core.LoadGame(gamePath); err != nil {
-				ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
-			} else {
-				m.WarpToQuickMenu()
+		err := core.Load(state.CorePath)
+		if err == nil {
+			if len(gamePath) > 0 {
+				err := core.LoadGame(gamePath)
+				if err != nil {
+					ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
+				} else {
+					m.WarpToQuickMenu()
+				}
 			}
+		} else {
+			ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
 		}
 	}
 

menu/input.go

@@ -196,7 +196,8 @@ func (m *Menu) ProcessHotkeys() {
 	// Toggle fullscreen if ActionFullscreenToggle is released
 	if input.Released[0][input.ActionFullscreenToggle] == 1 {
 		settings.Current.VideoFullscreen = !settings.Current.VideoFullscreen
-		m.SetFullscreen(settings.Current.VideoFullscreen)
+		m.Reconfigure(settings.Current.VideoFullscreen)
+		m.ContextReset()
 		err := settings.Save()
 		if err != nil {
 			ntf.DisplayAndLogf(ntf.Error, "Menu", "Error saving settings: %v", err)

menu/menu.go

@@ -102,12 +102,10 @@ func (m *Menu) ContextReset() {
 		m.icons[filename] = video.NewImage(path)
 	}
 
-	// Every retained scene's texture names belong to the old context.
-	for _, scene := range m.stack {
-		list := scene.Entry()
-		for i := range list.children {
-			list.children[i].thumbnail = 0
-		}
+	currentScreenIndex := len(m.stack) - 1
+	curList := m.stack[currentScreenIndex].Entry()
+	for i := range curList.children {
+		curList.children[i].thumbnail = 0
 	}
 }
 

menu/notifications.go

@@ -11,7 +11,6 @@ var severityBgColor map[ntf.Severity]video.Color
 // RenderNotifications draws the list of notification messages on the viewport
 func (m *Menu) RenderNotifications() {
 	fbw, fbh := m.GetFramebufferSize()
-	m.ratio = float32(fbw) / 1920
 	m.Font.UpdateResolution(fbw, fbh)
 	var h float32 = 75
 	stack := h

menu/scene_core_options.go

@@ -16,7 +16,7 @@ func buildCoreOptions() Scene {
 	var list sceneCoreOptions
 	list.label = "Core Options"
 
-	if core.Options == nil || len(core.Options.Vars) == 0 {
+	if core.Options == nil {
 		list.children = append(list.children, entry{
 			label: "No options",
 			icon:  "subsetting",

menu/scene_main.go

@@ -180,7 +180,7 @@ func gameExplorerCb(path string) {
 
 // Shutdown the operating system
 func cleanShutdown() {
-	core.Unload()
+	core.UnloadGame()
 	if err := exec.Command("/usr/sbin/shutdown", "-P", "now").Run(); err != nil {
 		ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
 	}
@@ -188,7 +188,7 @@ func cleanShutdown() {
 
 // Reboots the operating system
 func cleanReboot() {
-	core.Unload()
+	core.UnloadGame()
 	if err := exec.Command("/usr/sbin/shutdown", "-r", "now").Run(); err != nil {
 		ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
 	}

menu/scene_quick.go

@@ -1,7 +1,6 @@
 package menu
 
 import (
-	"github.com/libretro/ludo/core"
 	ntf "github.com/libretro/ludo/notifications"
 	"github.com/libretro/ludo/state"
 	"github.com/libretro/ludo/utils"
@@ -28,7 +27,7 @@ func buildQuickMenu() Scene {
 		label: "Reset",
 		icon:  "reset",
 		callbackOK: func() {
-			core.Reset()
+			state.Core.Reset()
 			state.MenuActive = false
 			state.FastForward = false
 		},
@@ -48,13 +47,11 @@ func buildQuickMenu() Scene {
 		icon:  "screenshot",
 		callbackOK: func() {
 			name := utils.DatedName(state.GamePath)
-			state.PendingScreenshotName = name
-			state.PendingScreenshotDone = func(err error) {
-				if err != nil {
-					ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
-				} else {
-					ntf.DisplayAndLog(ntf.Success, "Menu", "Took a screenshot.")
-				}
+			err := menu.TakeScreenshot(name)
+			if err != nil {
+				ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
+			} else {
+				ntf.DisplayAndLog(ntf.Success, "Menu", "Took a screenshot.")
 			}
 		},
 	})

menu/scene_savestates.go

@@ -26,19 +26,17 @@ func buildSavestates() Scene {
 		icon:  "savestate",
 		callbackOK: func() {
 			name := utils.DatedName(state.GamePath)
-			state.PendingScreenshotName = name
-			state.PendingScreenshotDone = func(err error) {
-				if err != nil {
-					ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
-				}
-				err = savestates.Save(name)
-				if err != nil {
-					ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
-				} else {
-					menu.stack[len(menu.stack)-1] = buildSavestates()
-					menu.tweens.FastForward()
-					ntf.DisplayAndLog(ntf.Success, "Menu", "State saved.")
-				}
+			err := menu.TakeScreenshot(name)
+			if err != nil {
+				ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
+			}
+			err = savestates.Save(name)
+			if err != nil {
+				ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())
+			} else {
+				menu.stack[len(menu.stack)-1] = buildSavestates()
+				menu.tweens.FastForward()
+				ntf.DisplayAndLog(ntf.Success, "Menu", "State saved.")
 			}
 		},
 	})

menu/scene_settings.go

@@ -164,7 +164,8 @@ var incrCallbacks = map[string]callbackIncrement{
 		v := f.Value().(bool)
 		v = !v
 		f.Set(v)
-		menu.SetFullscreen(settings.Current.VideoFullscreen)
+		menu.Reconfigure(settings.Current.VideoFullscreen)
+		menu.ContextReset()
 		settings.Save()
 	},
 	"VideoMonitorIndex": func(f *structs.Field, direction int) {
@@ -177,7 +178,8 @@ var incrCallbacks = map[string]callbackIncrement{
 			v = len(glfw.GetMonitors()) - 1
 		}
 		f.Set(v)
-		menu.SetFullscreen(settings.Current.VideoFullscreen)
+		menu.Reconfigure(settings.Current.VideoFullscreen)
+		menu.ContextReset()
 		settings.Save()
 	},
 	"VideoFilter": func(f *structs.Field, direction int) {

menu/scene_updater.go

@@ -90,7 +90,7 @@ func (s *sceneUpdater) update(dt float32) {
 		s.children[0].icon = "reload"
 		s.children[0].callbackOK = func() {
 			cmd := exec.Command("/usr/sbin/shutdown", "-r", "now")
-			core.Unload()
+			core.UnloadGame()
 			err := cmd.Run()
 			if err != nil {
 				ntf.DisplayAndLog(ntf.Error, "Menu", err.Error())

options/options.go

@@ -50,17 +50,13 @@ func New(vars []VariableInterface) (*Options, error) {
 
 	// Cache core options
 	for _, v := range vars {
-		choices := v.Choices()
-		// A core may expose an empty selector, e.g. when no BIOS files are found.
-		if len(choices) == 0 {
-			continue
-		}
+		v := v
 		o.Vars = append(o.Vars, &Variable{
 			Key:     v.Key(),
 			Desc:    v.Desc(),
-			Choices: choices,
+			Choices: v.Choices(),
 			Default: v.DefaultValue(),
-			Choice:  utils.IndexOfString(v.DefaultValue(), choices),
+			Choice:  utils.IndexOfString(v.DefaultValue(), v.Choices()),
 		})
 	}
 	o.Updated = true

patch/ips.go

@@ -33,6 +33,7 @@ func ipsAllocTargetData(patch, source []byte) ([]byte, error) {
 				size |= int(patch[offset]) << 8
 				offset++
 				size |= int(patch[offset]) << 0
+				offset++
 				targetLength = size
 				prov := make([]byte, targetLength)
 				return prov, nil
@@ -116,7 +117,15 @@ func applyIPS(patch, source []byte) (*[]byte, error) {
 		offset++
 
 		if address == EOF {
-			if offset == len(patch) || offset == len(patch)-3 {
+			if offset == len(patch) {
+				return &targetData, nil
+			} else if offset == len(patch)-3 {
+				size := int(patch[offset]) << 16
+				offset++
+				size |= int(patch[offset]) << 8
+				offset++
+				size |= int(patch[offset]) << 0
+				offset++
 				return &targetData, nil
 			}
 		}

savestates/savestates.go

@@ -6,14 +6,15 @@ import (
 	"os"
 	"path/filepath"
 
-	"github.com/libretro/ludo/core"
 	"github.com/libretro/ludo/settings"
+	"github.com/libretro/ludo/state"
 )
 
 // Save the current state to the filesystem. name is the name of the
 // savestate file to save to, without extension.
 func Save(name string) error {
-	bytes, err := core.Serialize()
+	s := state.Core.SerializeSize()
+	bytes, err := state.Core.Serialize(s)
 	if err != nil {
 		return err
 	}
@@ -27,9 +28,11 @@ func Save(name string) error {
 
 // Load the state from the filesystem
 func Load(path string) error {
+	s := state.Core.SerializeSize()
 	bytes, err := os.ReadFile(path)
 	if err != nil {
 		return err
 	}
-	return core.Unserialize(bytes)
+	err = state.Core.Unserialize(bytes, s)
+	return err
 }

settings/defaults.go

@@ -43,17 +43,13 @@ func defaultSettings() Settings {
 			"Nintendo - Game Boy Advance":                    "mgba_libretro",
 			"Nintendo - Game Boy Color":                      "gambatte_libretro",
 			"Nintendo - Game Boy":                            "gambatte_libretro",
-			"Nintendo - GameCube":                            "dolphin_libretro",
-			"Nintendo - Nintendo 3DS":                        "citra_libretro",
 			"Nintendo - Nintendo 64":                         "mupen64plus_next_libretro",
 			"Nintendo - Nintendo Entertainment System":       "fceumm_libretro",
 			"Nintendo - Nintendo DS":                         "melonds_libretro",
 			"Nintendo - Pokemon Mini":                        "pokemini_libretro",
 			"Nintendo - Super Nintendo Entertainment System": "snes9x_libretro",
 			"Nintendo - Virtual Boy":                         "mednafen_vb_libretro",
-			"Nintendo - Wii":                                 "dolphin_libretro",
 			"Sega - 32X":                                     "picodrive_libretro",
-			"Sega - Dreamcast":                               "flycast_libretro",
 			"Sega - Game Gear":                               "genesis_plus_gx_libretro",
 			"Sega - Master System - Mark III":                "genesis_plus_gx_libretro",
 			"Sega - Mega Drive - Genesis":                    "genesis_plus_gx_libretro",
@@ -64,8 +60,6 @@ func defaultSettings() Settings {
 			"SNK - Neo Geo Pocket Color":                     "mednafen_ngp_libretro",
 			"SNK - Neo Geo Pocket":                           "mednafen_ngp_libretro",
 			"Sony - PlayStation":                             playstationCore,
-			"Sony - PlayStation 2":                           "pcsx2_libretro",
-			"Sony - PlayStation Portable":                    "ppsspp_libretro",
 		},
 		FileDirectory:        usr.HomeDir,
 		CoresDirectory:       "./cores",

state/state.go

@@ -33,13 +33,3 @@ var LudOS bool
 
 // FastForward will run the core as fast as possible
 var FastForward bool
-
-// PendingScreenshotName is the next screenshot capture requested by the UI.
-var PendingScreenshotName string
-
-// PendingScreenshotDone is called after the deferred screenshot capture completes.
-var PendingScreenshotDone func(error)
-
-// MenuContextResetNeeded requests re-uploading menu GL assets after the
-// frontend window/context is recreated.
-var MenuContextResetNeeded bool

video/context_gl_test.go

@@ -1,190 +0,0 @@
-//go:build gltest && !darwin
-
-package video
-
-import (
-	"runtime"
-	"testing"
-
-	"github.com/go-gl/gl/v2.1/gl"
-	"github.com/go-gl/glfw/v3.4/glfw"
-	"github.com/go-gl/mathgl/mgl32"
-	"github.com/libretro/ludo/libretro"
-	"github.com/libretro/ludo/state"
-)
-
-// Run with go test -tags 'wayland gltest' ./video on a graphical session.
-func TestHardwareContextIsolation(t *testing.T) {
-	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
-	if err := glfw.Init(); err != nil {
-		t.Fatal(err)
-	}
-	defer glfw.Terminate()
-	glfw.DefaultWindowHints()
-	glfw.WindowHint(glfw.Visible, glfw.False)
-	glfw.WindowHint(glfw.ContextVersionMajor, 3)
-	glfw.WindowHint(glfw.ContextVersionMinor, 3)
-	glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
-	w, err := glfw.CreateWindow(128, 96, "Ludo GL test", nil, nil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer w.Destroy()
-	w.MakeContextCurrent()
-	if err := initGL(); err != nil {
-		t.Fatal(err)
-	}
-	t.Log("GL:", gl.GoStr(gl.GetString(gl.VERSION)))
-
-	oldCore, oldRunning := state.Core, state.CoreRunning
-	defer func() { state.Core, state.CoreRunning = oldCore, oldRunning }()
-	hw := &libretro.HWRenderCallback{HWContextType: libretro.HWContextOpenGLCore, VersionMajor: 3, VersionMinor: 3}
-	state.Core = &libretro.Core{HWRenderCallback: hw}
-	state.CoreRunning = true
-	v := &Video{Window: w, identityMat: mgl32.Ident4(), Geom: libretro.GameGeometry{MaxWidth: 64, MaxHeight: 64}}
-	v.SetHWRenderContext(hw)
-	v.ensurePixelFormatDefaults()
-	v.resetGameTexture(64, 64)
-	hw.ContextReset = func() {
-		if glfw.GetCurrentContext() != v.HWWindow {
-			t.Fatal("context_reset ran outside the HW context")
-		}
-	}
-	if err := v.ResetHWContext(); err != nil {
-		t.Fatal(err)
-	}
-	defer v.DestroySharedHWContext()
-	if glfw.GetCurrentContext() != w || v.HWWindow == nil || v.HWWindow == w {
-		t.Fatal("reset did not return to an independent frontend context")
-	}
-
-	v.BeginCore()
-	var readFBO, texture, pbo uint32
-	gl.GenFramebuffers(1, &readFBO)
-	gl.BindFramebuffer(gl.READ_FRAMEBUFFER, readFBO)
-	gl.GenTextures(1, &texture)
-	gl.ActiveTexture(gl.TEXTURE1)
-	gl.BindTexture(gl.TEXTURE_2D, texture)
-	gl.GenBuffers(1, &pbo)
-	gl.BindBuffer(gl.PIXEL_PACK_BUFFER, pbo)
-	gl.PixelStorei(gl.PACK_ROW_LENGTH, 256)
-	gl.Enable(gl.BLEND)
-	gl.Enable(gl.SCISSOR_TEST)
-	gl.BlendEquation(gl.FUNC_REVERSE_SUBTRACT)
-	v.EndCore()
-	v.BeginFrontendFrame()
-	checkInt := func(name uint32, want int32) {
-		t.Helper()
-		var got int32
-		gl.GetIntegerv(name, &got)
-		if got != want {
-			t.Errorf("GL state %#x: got %d, want %d", name, got, want)
-		}
-	}
-	checkInt(gl.PIXEL_PACK_BUFFER_BINDING, 0)
-	checkInt(gl.PACK_ROW_LENGTH, 0)
-	checkInt(gl.READ_FRAMEBUFFER_BINDING, 0)
-	checkInt(gl.BLEND_EQUATION_RGB, gl.FUNC_ADD)
-	v.BeginCore()
-	checkInt(gl.PIXEL_PACK_BUFFER_BINDING, int32(pbo))
-	checkInt(gl.PACK_ROW_LENGTH, 256)
-	checkInt(gl.READ_FRAMEBUFFER_BINDING, int32(readFBO))
-	checkInt(gl.DRAW_FRAMEBUFFER_BINDING, int32(v.fboID))
-	checkInt(gl.BLEND_EQUATION_RGB, gl.FUNC_REVERSE_SUBTRACT)
-	checkInt(gl.ACTIVE_TEXTURE, gl.TEXTURE1)
-	checkInt(gl.TEXTURE_BINDING_2D, int32(texture))
-	if !gl.IsEnabled(gl.BLEND) || !gl.IsEnabled(gl.SCISSOR_TEST) {
-		t.Error("frontend rendering changed core enables")
-	}
-	gl.BindBuffer(gl.PIXEL_PACK_BUFFER, 0)
-	gl.PixelStorei(gl.PACK_ROW_LENGTH, 0)
-	gl.Disable(gl.SCISSOR_TEST)
-	gl.Disable(gl.BLEND)
-	gl.BindFramebuffer(gl.READ_FRAMEBUFFER, v.fboID)
-
-	// Verify the produced pixels are visible through the shared texture.
-	gl.ClearColor(1, 0, 0, 1)
-	gl.Clear(gl.COLOR_BUFFER_BIT)
-	v.EndCore()
-	var frontendFBO uint32
-	gl.GenFramebuffers(1, &frontendFBO)
-	gl.BindFramebuffer(gl.FRAMEBUFFER, frontendFBO)
-	gl.FramebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, v.texID, 0)
-	var pixel [4]byte
-	gl.ReadPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(&pixel[0]))
-	if pixel != [4]byte{255, 0, 0, 255} {
-		t.Errorf("shared frame: got %v, want red", pixel)
-	}
-	v.BeginFrontendFrame()
-
-	// Backbuffer snapshots must retain their orientation for either core origin.
-	v.defaultProgram, err = newProgram(vertexShader, defaultFragmentShader)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gl.GenVertexArrays(1, &v.vao)
-	gl.BindVertexArray(v.vao)
-	gl.GenBuffers(1, &v.vbo)
-	gl.BindBuffer(gl.ARRAY_BUFFER, v.vbo)
-	vert := uint32(gl.GetAttribLocation(v.defaultProgram, gl.Str("vert\x00")))
-	uv := uint32(gl.GetAttribLocation(v.defaultProgram, gl.Str("vertTexCoord\x00")))
-	gl.EnableVertexAttribArray(vert)
-	gl.VertexAttribPointerWithOffset(vert, 2, gl.FLOAT, false, 16, 0)
-	gl.EnableVertexAttribArray(uv)
-	gl.VertexAttribPointerWithOffset(uv, 2, gl.FLOAT, false, 16, 8)
-	v.width, v.height = 64, 64
-	for _, bottomLeft := range []bool{false, true} {
-		hw.BottomLeftOrigin = bottomLeft
-		v.BeginFrontendFrame()
-		fbw, fbh := w.GetFramebufferSize()
-		v.Geom.AspectRatio = float64(fbw) / float64(fbh)
-		v.presentW, v.presentH = int32(fbw), int32(fbh)
-		gl.ClearColor(1, 0, 0, 1)
-		gl.Clear(gl.COLOR_BUFFER_BIT)
-		gl.Enable(gl.SCISSOR_TEST)
-		gl.Scissor(0, int32(fbh/2), int32(fbw), int32(fbh/2))
-		gl.ClearColor(0, 0, 1, 1)
-		gl.Clear(gl.COLOR_BUFFER_BIT)
-		gl.Disable(gl.SCISSOR_TEST)
-		v.CachePresentedFrame()
-		if !v.RenderCachedFrame() {
-			t.Fatal("cached frame unavailable")
-		}
-		gl.ReadPixels(1, 1, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(&pixel[0]))
-		if pixel != [4]byte{255, 0, 0, 255} {
-			t.Errorf("cached frame, bottom-left=%v: got %v, want red", bottomLeft, pixel)
-		}
-	}
-
-	hw.ContextDestroy = func() {
-		if glfw.GetCurrentContext() != v.HWWindow {
-			t.Error("context_destroy ran outside the HW context")
-		}
-	}
-	v.RunContextDestroy()
-	v.ResetCoreState()
-	if !gl.IsFramebuffer(frontendFBO) {
-		t.Error("HW teardown deleted a frontend framebuffer with the same name")
-	}
-	if v.fboID != 0 || v.HWWindow != nil || v.cachedFrameValid || v.width != 0 {
-		t.Error("HW teardown left stale core resources")
-	}
-
-	// A subsequent core must get a fresh context, including on the GL 2.x sync fallback.
-	if err := v.ResetHWContext(); err != nil {
-		t.Fatal(err)
-	}
-	v.hwSync = false
-	v.BeginCore()
-	checkInt(gl.PACK_ROW_LENGTH, 0)
-	checkInt(gl.PIXEL_PACK_BUFFER_BINDING, 0)
-	checkInt(gl.BLEND_EQUATION_RGB, gl.FUNC_ADD)
-	if gl.IsEnabled(gl.BLEND) || gl.IsEnabled(gl.SCISSOR_TEST) {
-		t.Error("new core inherited the previous core's enables")
-	}
-	v.EndCore()
-	if e := gl.GetError(); e != gl.NO_ERROR {
-		t.Errorf("GL error: %#x", e)
-	}
-}

video/default_vert_shader.go

@@ -4,9 +4,14 @@ var vertexShader = `
 #if __VERSION__ >= 130
 #define COMPAT_VARYING out
 #define COMPAT_ATTRIBUTE in
+#define COMPAT_TEXTURE texture
+#define COMPAT_FRAGCOLOR FragColor
+out vec4 COMPAT_FRAGCOLOR;
 #else
 #define COMPAT_VARYING varying
 #define COMPAT_ATTRIBUTE attribute
+#define COMPAT_TEXTURE texture2D
+#define COMPAT_FRAGCOLOR gl_FragColor
 #endif
 
 COMPAT_ATTRIBUTE vec2 vert;
@@ -14,10 +19,8 @@ COMPAT_ATTRIBUTE vec2 vertTexCoord;
 
 COMPAT_VARYING vec2 fragTexCoord;
 
-uniform mat4 MVP;
-
 void main() {
   fragTexCoord = vertTexCoord;
-  gl_Position = vec4(vert, 0.0, 1.0) * MVP;
+  gl_Position = vec4(vert, 0.0, 1.0);
 }
 ` + "\x00"

video/framebuffer.go

@@ -1,83 +0,0 @@
-package video
-
-import (
-	"log"
-
-	"github.com/go-gl/gl/v2.1/gl"
-	"github.com/go-gl/mathgl/mgl32"
-	"github.com/libretro/ludo/libretro"
-	"github.com/libretro/ludo/state"
-)
-
-// InitFramebuffer initializes and configures the video frame buffer based on
-// informations from the HWRenderCallback of the libretro core.
-func (video *Video) InitFramebuffer() {
-	width := int32(video.Geom.MaxWidth)
-	height := int32(video.Geom.MaxHeight)
-	video.texWidth = width
-	video.texHeight = height
-
-	log.Printf("[Video]: Initializing HW render (%v x %v).\n", width, height)
-
-	gl.ActiveTexture(gl.TEXTURE0)
-	gl.BindTexture(gl.TEXTURE_2D, video.texID)
-	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, width, height, 0, gl.RGBA, gl.UNSIGNED_BYTE, nil)
-
-	genFramebuffers(1, &video.fboID)
-	bindFramebuffer(gl.FRAMEBUFFER, video.fboID)
-	libretro.SetCurrentFramebufferValue(uintptr(video.fboID))
-	framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, video.texID, 0)
-
-	hw := state.Core.HWRenderCallback
-	if hw.Depth {
-		genRenderbuffers(1, &video.rboID)
-		bindRenderbuffer(gl.RENDERBUFFER, video.rboID)
-		format := gl.DEPTH_COMPONENT16
-		if hw.Stencil {
-			format = gl.DEPTH24_STENCIL8
-		}
-		renderbufferStorage(gl.RENDERBUFFER, uint32(format), width, height)
-		bindRenderbuffer(gl.RENDERBUFFER, 0)
-
-		// Separate attachment points work with both core and EXT framebuffers.
-		framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, gl.RENDERBUFFER, video.rboID)
-		if hw.Stencil {
-			framebufferRenderbuffer(gl.FRAMEBUFFER, gl.STENCIL_ATTACHMENT, gl.RENDERBUFFER, video.rboID)
-		}
-	}
-
-	// Default origin is top left
-	video.orthoMat = mgl32.Ortho2D(-1, 1, -1, 1)
-	if hw.BottomLeftOrigin {
-		video.orthoMat = mgl32.Ortho2D(-1, 1, 1, -1)
-	}
-
-	if st := checkFramebufferStatus(gl.FRAMEBUFFER); st != gl.FRAMEBUFFER_COMPLETE {
-		log.Fatalf("[Video] Framebuffer is not complete. Error: %v\n", st)
-	}
-
-	gl.ClearColor(0, 0, 0, 1)
-	if hw.Depth && hw.Stencil {
-		gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT | gl.STENCIL_BUFFER_BIT)
-	} else if hw.Depth {
-		gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
-	} else {
-		gl.Clear(gl.COLOR_BUFFER_BIT)
-	}
-}
-
-func bindBackbuffer() {
-	bindFramebuffer(gl.FRAMEBUFFER, 0)
-}
-
-func (video *Video) destroyFramebuffer() {
-	bindBackbuffer()
-	if video.rboID != 0 {
-		deleteRenderbuffers(1, &video.rboID)
-		video.rboID = 0
-	}
-	if video.fboID != 0 {
-		deleteFramebuffers(1, &video.fboID)
-		video.fboID = 0
-	}
-}

video/gfx.go

@@ -124,7 +124,11 @@ func (video *Video) ScissorEnd() {
 	gl.Disable(gl.SCISSOR_TEST)
 }
 
-func vertexArrayForFramebuffer(x, y, w, h, scale, ffbw, ffbh float32) []float32 {
+func (video *Video) vertexArray(x, y, w, h, scale float32) []float32 {
+	fbw, fbh := video.Window.GetFramebufferSize()
+	ffbw := float32(fbw)
+	ffbh := float32(fbh)
+
 	w *= scale
 	h *= scale
 
@@ -139,11 +143,6 @@ func vertexArrayForFramebuffer(x, y, w, h, scale, ffbw, ffbh float32) []float32
 	}
 }
 
-func (video *Video) vertexArray(x, y, w, h, scale float32) []float32 {
-	fbw, fbh := video.Window.GetFramebufferSize()
-	return vertexArrayForFramebuffer(x, y, w, h, scale, float32(fbw), float32(fbh))
-}
-
 // DrawBorder draws a colored rectangle border
 func (video *Video) DrawBorder(x, y, w, h, borderWidth float32, c Color) {
 	va := video.vertexArray(x, y, w, h, 1.0)

video/gl.go

@@ -1,63 +0,0 @@
-package video
-
-import (
-	"errors"
-
-	"github.com/go-gl/gl/v2.1/gl"
-	"github.com/go-gl/glfw/v3.4/glfw"
-)
-
-var (
-	glslVersion             = "#version 120\n"
-	genVertexArrays         = gl.GenVertexArrays
-	bindVertexArray         = gl.BindVertexArray
-	genFramebuffers         = gl.GenFramebuffers
-	bindFramebuffer         = gl.BindFramebuffer
-	deleteFramebuffers      = gl.DeleteFramebuffers
-	framebufferTexture2D    = gl.FramebufferTexture2D
-	checkFramebufferStatus  = gl.CheckFramebufferStatus
-	genRenderbuffers        = gl.GenRenderbuffers
-	bindRenderbuffer        = gl.BindRenderbuffer
-	deleteRenderbuffers     = gl.DeleteRenderbuffers
-	renderbufferStorage     = gl.RenderbufferStorage
-	framebufferRenderbuffer = gl.FramebufferRenderbuffer
-)
-
-// The frontend and hidden core context use the same hints. Select their API
-// from the actual context capabilities, including macOS's legacy extensions.
-func initGL() error {
-	if err := gl.Init(); err != nil {
-		return err
-	}
-	window := glfw.GetCurrentContext()
-	major, minor := window.GetAttrib(glfw.ContextVersionMajor), window.GetAttrib(glfw.ContextVersionMinor)
-	glslVersion = "#version 120\n"
-	if major > 3 || (major == 3 && minor >= 2) {
-		glslVersion = "#version 150\n"
-	} else if major == 3 {
-		glslVersion = "#version 130\n"
-	}
-
-	genVertexArrays, bindVertexArray = gl.GenVertexArrays, gl.BindVertexArray
-	genFramebuffers, bindFramebuffer, deleteFramebuffers = gl.GenFramebuffers, gl.BindFramebuffer, gl.DeleteFramebuffers
-	framebufferTexture2D, checkFramebufferStatus = gl.FramebufferTexture2D, gl.CheckFramebufferStatus
-	genRenderbuffers, bindRenderbuffer, deleteRenderbuffers = gl.GenRenderbuffers, gl.BindRenderbuffer, gl.DeleteRenderbuffers
-	renderbufferStorage, framebufferRenderbuffer = gl.RenderbufferStorage, gl.FramebufferRenderbuffer
-
-	if major < 3 && !glfw.ExtensionSupported("GL_ARB_vertex_array_object") {
-		if !glfw.ExtensionSupported("GL_APPLE_vertex_array_object") {
-			return errors.New("OpenGL vertex array objects are not supported")
-		}
-		genVertexArrays, bindVertexArray = gl.GenVertexArraysAPPLE, gl.BindVertexArrayAPPLE
-	}
-	if major < 3 && !glfw.ExtensionSupported("GL_ARB_framebuffer_object") {
-		if !glfw.ExtensionSupported("GL_EXT_framebuffer_object") {
-			return errors.New("OpenGL framebuffer objects are not supported")
-		}
-		genFramebuffers, bindFramebuffer, deleteFramebuffers = gl.GenFramebuffersEXT, gl.BindFramebufferEXT, gl.DeleteFramebuffersEXT
-		framebufferTexture2D, checkFramebufferStatus = gl.FramebufferTexture2DEXT, gl.CheckFramebufferStatusEXT
-		genRenderbuffers, bindRenderbuffer, deleteRenderbuffers = gl.GenRenderbuffersEXT, gl.BindRenderbufferEXT, gl.DeleteRenderbuffersEXT
-		renderbufferStorage, framebufferRenderbuffer = gl.RenderbufferStorageEXT, gl.FramebufferRenderbufferEXT
-	}
-	return nil
-}

video/refresh_test.go

@@ -1,25 +0,0 @@
-package video
-
-import (
-	"testing"
-
-	"github.com/libretro/ludo/libretro"
-)
-
-func TestDuplicateFramePreservesDimensions(t *testing.T) {
-	v := &Video{}
-	v.Refresh(libretro.HWFrameBufferValid, 320, 240, 0)
-	v.Refresh(nil, 0, 0, 0)
-	if v.width != 320 || v.height != 240 || v.data != libretro.HWFrameBufferValid || !v.needUpload {
-		t.Fatal("NULL refresh discarded the pending frame")
-	}
-	v.needUpload = false
-	v.Refresh(nil, 640, 480, 0)
-	if v.width != 320 || v.height != 240 || v.needUpload {
-		t.Fatal("NULL refresh changed the previously presented frame")
-	}
-}
-
-func TestContextDestroyWithoutCore(t *testing.T) {
-	(&Video{}).RunContextDestroy()
-}

video/screenshot.go

@@ -1,7 +1,6 @@
 package video
 
 import (
-	"errors"
 	"image"
 	"image/png"
 	"os"
@@ -14,33 +13,41 @@ import (
 	"github.com/libretro/ludo/state"
 )
 
-func (video *Video) captureBackbufferScreenshot(name string) error {
-	outW, outH := video.Geom.BaseWidth, video.Geom.BaseHeight
-	if outW < 1 || outH < 1 {
-		return errors.New("invalid screenshot output size")
-	}
+// During the TakeScreenshot step, we need to render the current game frame at
+// the right resolution to later capture it using ReadPixels. renderScreenshot
+// taking care of this.
+func (video *Video) renderScreenshot() {
+	va := video.vertexArray(0, 0, float32(video.Geom.BaseWidth), float32(video.Geom.BaseHeight), 1.0)
+	gl.BindBuffer(gl.ARRAY_BUFFER, video.vbo)
+	gl.BufferData(gl.ARRAY_BUFFER, len(va)*4, gl.Ptr(va), gl.STATIC_DRAW)
 
-	x := video.presentX
-	y := video.presentY
-	w := video.presentW
-	h := video.presentH
-	if !state.CoreRunning || video.width < 1 || video.height < 1 || w < 1 || h < 1 {
-		return errors.New("no game frame to capture")
-	}
+	bindVertexArray(video.vao)
 
-	var oldReadBuffer int32
-	gl.GetIntegerv(gl.READ_BUFFER, &oldReadBuffer)
-	gl.ReadBuffer(gl.BACK)
+	gl.BindTexture(gl.TEXTURE_2D, video.texID)
+	gl.BindBuffer(gl.ARRAY_BUFFER, video.vbo)
 
-	img := image.NewRGBA(image.Rect(0, 0, int(w), int(h)))
-	gl.Finish()
-	gl.ReadPixels(x, y, w, h, gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(img.Pix))
-	gl.ReadBuffer(uint32(oldReadBuffer))
+	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
+}
 
-	flipped := imaging.FlipV(img)
-	if flipped.Bounds().Dx() != outW || flipped.Bounds().Dy() != outH {
-		flipped = imaging.Resize(flipped, outW, outH, imaging.Linear)
-	}
+// TakeScreenshot captures the ouput of video.Render and writes it to a file
+func (video *Video) TakeScreenshot(name string) error {
+	state.MenuActive = false
+	defer func() { state.MenuActive = true }()
+
+	gl.UseProgram(video.defaultProgram)
+
+	video.renderScreenshot()
+
+	img := image.NewRGBA(image.Rect(0, 0, video.Geom.BaseWidth, video.Geom.BaseHeight))
+
+	_, fbh := video.Window.GetFramebufferSize()
+
+	gl.ReadPixels(
+		0, int32(fbh-video.Geom.BaseHeight),
+		int32(video.Geom.BaseWidth), int32(video.Geom.BaseHeight),
+		gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(img.Pix))
+
+	gl.UseProgram(video.program)
 
 	err := os.MkdirAll(settings.Current.ScreenshotsDirectory, os.ModePerm)
 	if err != nil {
@@ -52,13 +59,8 @@ func (video *Video) captureBackbufferScreenshot(name string) error {
 	if err != nil {
 		return err
 	}
-	defer fd.Close()
+
+	flipped := imaging.FlipV(img)
 
 	return png.Encode(fd, flipped)
 }
-
-// TakeScreenshotInFrontendFrame captures a screenshot while the caller already
-// owns a frontend frame and has already rendered the current game frame.
-func (video *Video) TakeScreenshotInFrontendFrame(name string) error {
-	return video.captureBackbufferScreenshot(name)
-}

video/shader_utils.go

@@ -5,7 +5,6 @@ import (
 	"strings"
 
 	"github.com/go-gl/gl/v2.1/gl"
-	"github.com/go-gl/mathgl/mgl32"
 )
 
 func newProgram(vertexShaderSource, fragmentShaderSource string) (uint32, error) {
@@ -23,9 +22,6 @@ func newProgram(vertexShaderSource, fragmentShaderSource string) (uint32, error)
 
 	gl.AttachShader(program, vertexShader)
 	gl.AttachShader(program, fragmentShader)
-	// Game and menu programs share a VAO, so their attribute locations must match.
-	gl.BindAttribLocation(program, 0, gl.Str("vert\x00"))
-	gl.BindAttribLocation(program, 1, gl.Str("vertTexCoord\x00"))
 	gl.LinkProgram(program)
 
 	var status int32
@@ -43,24 +39,13 @@ func newProgram(vertexShaderSource, fragmentShaderSource string) (uint32, error)
 	gl.DeleteShader(vertexShader)
 	gl.DeleteShader(fragmentShader)
 
-	// Only the core rendering code uses MVPs so we set it to identity
-	// to avoid issues with other parts of the program
-	gl.UseProgram(program)
-	mvp := gl.GetUniformLocation(program, gl.Str("MVP\x00"))
-
-	if mvp != -1 {
-		IdentityMatrix := mgl32.Ident4()
-		gl.UniformMatrix4fv(mvp, 1, false, &IdentityMatrix[0])
-	}
-	gl.UseProgram(0)
-
 	return program, nil
 }
 
 func compileShader(source string, shaderType uint32) (uint32, error) {
 	shader := gl.CreateShader(shaderType)
 
-	csources, free := gl.Strs(glslVersion + source)
+	csources, free := gl.Strs(source)
 	gl.ShaderSource(shader, 1, csources, nil)
 	free()
 	gl.CompileShader(shader)

video/upload_gl_test.go

@@ -1,78 +0,0 @@
-//go:build gltest && linux
-
-package video
-
-import (
-	"bytes"
-	"runtime"
-	"testing"
-	"unsafe"
-
-	"github.com/go-gl/gl/v2.1/gl"
-	"github.com/go-gl/glfw/v3.4/glfw"
-	"github.com/libretro/ludo/libretro"
-	"golang.org/x/sys/unix"
-)
-
-func TestSoftwareFrameUploadBounds(t *testing.T) {
-	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
-	if err := glfw.Init(); err != nil {
-		t.Fatal(err)
-	}
-	defer glfw.Terminate()
-	glfw.DefaultWindowHints()
-	glfw.WindowHint(glfw.Visible, glfw.False)
-	w, err := glfw.CreateWindow(32, 32, "Ludo upload test", nil, nil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer w.Destroy()
-	w.MakeContextCurrent()
-	if err := initGL(); err != nil {
-		t.Fatal(err)
-	}
-
-	v := &Video{Geom: libretro.GameGeometry{MaxWidth: 64, MaxHeight: 64}}
-	v.SetPixelFormat(libretro.PixelFormatXRGB8888)
-	v.resetGameTexture(1, 1)
-	defer gl.DeleteTextures(1, &v.texID)
-	v.program, err = newProgram(vertexShader, defaultFragmentShader)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer gl.DeleteProgram(v.program)
-
-	const width, height, pitch = 32, 32, 32 * 4
-	page := unix.Getpagesize()
-	memory, err := unix.Mmap(-1, 0, page*2, unix.PROT_READ|unix.PROT_WRITE, unix.MAP_ANON|unix.MAP_PRIVATE)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer unix.Munmap(memory)
-	if err := unix.Mprotect(memory[page:], unix.PROT_NONE); err != nil {
-		t.Fatal(err)
-	}
-	// The core supplies only the current frame, ending at a protected page.
-	frame := memory[page-pitch*height : page]
-	for i := range frame {
-		frame[i] = byte(i)
-	}
-	v.Refresh(unsafe.Pointer(&frame[0]), width, height, pitch)
-	v.uploadTexture()
-
-	var texWidth, texHeight int32
-	gl.GetTexLevelParameteriv(gl.TEXTURE_2D, 0, gl.TEXTURE_WIDTH, &texWidth)
-	gl.GetTexLevelParameteriv(gl.TEXTURE_2D, 0, gl.TEXTURE_HEIGHT, &texHeight)
-	if texWidth != width || texHeight != height {
-		t.Fatalf("texture size = %dx%d, want %dx%d", texWidth, texHeight, width, height)
-	}
-	pixels := make([]byte, len(frame))
-	gl.GetTexImage(gl.TEXTURE_2D, 0, v.pixType, v.pixFmt, gl.Ptr(pixels))
-	if !bytes.Equal(pixels, frame) {
-		t.Error("uploaded pixels differ from the supplied frame")
-	}
-	if err := gl.GetError(); err != gl.NO_ERROR {
-		t.Errorf("GL error: %#x", err)
-	}
-}

video/video.go

@@ -4,14 +4,12 @@
 package video
 
 import (
-	"errors"
 	"log"
 	"path/filepath"
 	"unsafe"
 
 	"github.com/go-gl/gl/v2.1/gl"
 	"github.com/go-gl/glfw/v3.4/glfw"
-	"github.com/go-gl/mathgl/mgl32"
 	"github.com/libretro/ludo/libretro"
 	"github.com/libretro/ludo/settings"
 	"github.com/libretro/ludo/state"
@@ -19,16 +17,11 @@ import (
 
 // Video holds the state of the video package
 type Video struct {
-	Window   *glfw.Window
-	HWWindow *glfw.Window // hidden core context; shares objects, not GL state, with Window
-	Geom     libretro.GameGeometry
-	Font     *Font
-	FontSm   *Font
-	FontLg   *Font
-	title    string
-
-	windowedX, windowedY          int
-	windowedWidth, windowedHeight int
+	Window *glfw.Window
+	Geom   libretro.GameGeometry
+	Font   *Font
+	FontSm *Font
+	FontLg *Font
 
 	program              uint32 // current program used for the game quad
 	defaultProgram       uint32 // default program used for the game quad
@@ -41,20 +34,6 @@ type Video struct {
 	vao                  uint32 // vertex array object
 	vbo                  uint32 // vertex buffer object
 	texID                uint32 // texture id
-	fboID                uint32 // framebuffer id for hw-render cores
-	rboID                uint32 // depth/stencil renderbuffer for hw-render cores
-	identityMat          mgl32.Mat4
-	orthoMat             mgl32.Mat4
-	texWidth             int32
-	texHeight            int32
-	presentX             int32
-	presentY             int32
-	presentW             int32
-	presentH             int32
-	cachedFrameTexID     uint32
-	cachedFrameW         int32
-	cachedFrameH         int32
-	cachedFrameValid     bool
 
 	pitch         int32  // pitch set by the refresh callback
 	pixFmt        uint32 // format set by the environment callback
@@ -65,190 +44,21 @@ type Video struct {
 
 	needUpload bool // true when the texture needs to be uploaded to the GPU
 	data       unsafe.Pointer
-
-	hwContextType       uint32
-	hwContextMajor      int
-	hwContextMinor      int
-	hwDebugContext      bool
-	hwContextConfigured bool
-	hwSync              bool
 }
 
 // Init instanciates the video package
 func Init(fullscreen bool) *Video {
-	vid := &Video{title: "Ludo"}
-	vid.identityMat = mgl32.Ident4()
+	vid := &Video{}
 	vid.Configure(fullscreen)
 	return vid
 }
 
-// SetFullscreen changes the window mode or monitor without recreating GL contexts.
-func (video *Video) SetFullscreen(fullscreen bool) {
-	if fullscreen {
-		if video.Window.GetMonitor() == nil {
-			video.windowedWidth, video.windowedHeight = video.Window.GetSize()
-			// Wayland does not expose window positions.
-			if glfw.GetPlatform() != glfw.PlatformWayland {
-				video.windowedX, video.windowedY = video.Window.GetPos()
-			}
-		}
-		monitor := glfw.GetMonitors()[settings.Current.VideoMonitorIndex]
-		modes := monitor.GetVideoModes()
-		mode := modes[len(modes)-1]
-		video.Window.SetMonitor(monitor, 0, 0, mode.Width, mode.Height, mode.RefreshRate)
-	} else if video.Window.GetMonitor() != nil {
-		video.Window.SetMonitor(nil, video.windowedX, video.windowedY,
-			video.windowedWidth, video.windowedHeight, glfw.DontCare)
-	}
-}
-
-// ReconfigureHWContext recreates the visible window using the currently stored
-// HW context hints while preserving the current window size when windowed.
-func (video *Video) ReconfigureHWContext(fullscreen bool) error {
-	width := 384 * 2
-	height := 240 * 2
-	if video.Window != nil && !fullscreen {
-		width, height = video.Window.GetSize()
-		if width < 1 {
-			width = 384 * 2
-		}
-		if height < 1 {
-			height = 240 * 2
-		}
-	}
-	return video.configureWithSize(width, height, fullscreen)
-}
-
-// CreateSharedHWContext creates a hidden context shared with the visible frontend context.
-func (video *Video) CreateSharedHWContext() error {
-	if video.HWWindow != nil {
-		return nil
-	}
-
-	video.configureWindowHints()
-	glfw.WindowHint(glfw.Visible, glfw.False)
-	glfw.WindowHint(glfw.Focused, glfw.False)
-
-	width, height := video.Window.GetSize()
-	if width < 1 {
-		width = 1
-	}
-	if height < 1 {
-		height = 1
-	}
-
-	hwWindow, err := glfw.CreateWindow(width, height, "", nil, video.Window)
-	if err != nil {
-		return err
-	}
-
-	video.HWWindow = hwWindow
-	major := video.Window.GetAttrib(glfw.ContextVersionMajor)
-	minor := video.Window.GetAttrib(glfw.ContextVersionMinor)
-	video.hwSync = major > 3 || (major == 3 && minor >= 2) || glfw.ExtensionSupported("GL_ARB_sync")
-	return nil
-}
-
-// DestroySharedHWContext destroys the hidden shared context if it exists.
-func (video *Video) DestroySharedHWContext() {
-	if video.HWWindow != nil {
-		video.BeginCore()
-		video.destroyFramebuffer()
-		libretro.SetCurrentFramebufferValue(0)
-		video.EndCore()
-		video.HWWindow.Destroy()
-		video.HWWindow = nil
-	}
-}
-
-// MakeFrontendContextCurrent switches back to the visible frontend context.
-func (video *Video) MakeFrontendContextCurrent() {
+// Reconfigure destroys and recreates the window with new attributes
+func (video *Video) Reconfigure(fullscreen bool) {
 	if video.Window != nil {
-		video.Window.MakeContextCurrent()
-	}
-}
-
-// RunContextDestroy notifies the active core before its GL context is destroyed.
-func (video *Video) RunContextDestroy() {
-	if !state.CoreRunning || state.Core == nil || video.HWWindow == nil {
-		return
-	}
-	hw := state.Core.HWRenderCallback
-	if hw != nil && hw.ContextDestroy != nil {
-		video.BeginCore()
-		hw.ContextDestroy()
-		video.EndCore()
-	}
-}
-
-// ResetHWContext creates the core's render target and resets its renderer.
-func (video *Video) ResetHWContext() error {
-	if err := video.CreateSharedHWContext(); err != nil {
-		return err
-	}
-	video.BeginCore()
-	defer video.EndCore()
-	video.InitFramebuffer()
-	state.Core.HWRenderCallback.ContextReset()
-	return nil
-}
-
-// BeginCore enters the isolated context for run, reset, serialization or teardown.
-func (video *Video) BeginCore() {
-	if video.HWWindow != nil {
-		video.switchContext(video.HWWindow)
-	}
-}
-
-// EndCore returns to the frontend after the core's GL work.
-func (video *Video) EndCore() {
-	if video.HWWindow != nil {
-		video.switchContext(video.Window)
-	}
-}
-
-// ContextCallbacks returns paired release/acquire callbacks for synchronous
-// context handoffs between the frontend and native core threads.
-func (video *Video) ContextCallbacks() (release, acquire func()) {
-	var current *glfw.Window
-	release = func() {
-		current = nil
-		if video.Window == nil || state.Core == nil || state.Core.HWRenderCallback == nil {
-			return
-		}
-		current = glfw.GetCurrentContext()
-		// Before context_reset, HW negotiation may still use the visible context.
-		// Once the hidden context exists, leave the menu context on its own thread.
-		if video.HWWindow != nil && current != video.HWWindow {
-			current = nil
-		}
-		if current != nil {
-			glfw.DetachCurrentContext()
-		}
-	}
-	acquire = func() {
-		if current != nil {
-			current.MakeContextCurrent()
-		}
-	}
-	return
-}
-
-func (video *Video) switchContext(window *glfw.Window) {
-	if glfw.GetCurrentContext() == window {
-		return
-	}
-	// Order shared-texture writes and reads in both directions without a CPU wait.
-	if video.hwSync {
-		fence := gl.FenceSync(gl.SYNC_GPU_COMMANDS_COMPLETE, 0)
-		gl.Flush()
-		window.MakeContextCurrent()
-		gl.WaitSync(fence, 0, gl.TIMEOUT_IGNORED)
-		gl.DeleteSync(fence)
-	} else {
-		gl.Finish()
-		window.MakeContextCurrent()
+		video.Window.Destroy()
 	}
+	video.Configure(fullscreen)
 }
 
 // GetFramebufferSize retrieves the size, in pixels, of the framebuffer of the specified window.
@@ -261,69 +71,12 @@ func (video *Video) GetFramebufferSize() (int, int) {
 
 // SetTitle sets the window title, encoded as UTF-8, of the window.
 func (video *Video) SetTitle(title string) {
-	video.title = title
 	if video.Window == nil {
 		return
 	}
 	video.Window.SetTitle(title)
 }
 
-// SetHWRenderContext stores the context requested by the current libretro core.
-func (video *Video) SetHWRenderContext(hw *libretro.HWRenderCallback) {
-	if hw == nil {
-		video.hwContextType = 0
-		video.hwContextMajor = 0
-		video.hwContextMinor = 0
-		video.hwDebugContext = false
-		video.hwContextConfigured = false
-		return
-	}
-
-	video.hwContextType = hw.HWContextType
-	video.hwContextMajor = int(hw.VersionMajor)
-	video.hwContextMinor = int(hw.VersionMinor)
-	video.hwDebugContext = hw.DebugContext
-	video.hwContextConfigured = true
-}
-
-func (video *Video) configureWindowHints() {
-	glfw.DefaultWindowHints()
-
-	if !video.hwContextConfigured {
-		return
-	}
-
-	switch video.hwContextType {
-	case libretro.HWContextOpenGLCore:
-		major := video.hwContextMajor
-		minor := video.hwContextMinor
-		glfw.WindowHint(glfw.ClientAPI, glfw.OpenGLAPI)
-		glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLAnyProfile)
-		if major > 0 {
-			glfw.WindowHint(glfw.ContextVersionMajor, major)
-			glfw.WindowHint(glfw.ContextVersionMinor, minor)
-			if major > 3 || (major == 3 && minor >= 2) {
-				glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
-				glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
-			}
-		}
-	case libretro.HWContextOpenGL:
-		glfw.WindowHint(glfw.ClientAPI, glfw.OpenGLAPI)
-		if video.hwContextMajor > 0 {
-			glfw.WindowHint(glfw.ContextVersionMajor, video.hwContextMajor)
-			glfw.WindowHint(glfw.ContextVersionMinor, video.hwContextMinor)
-			if video.hwContextMajor > 3 || (video.hwContextMajor == 3 && video.hwContextMinor >= 2) {
-				glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCompatProfile)
-				glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.False)
-			}
-		}
-	}
-
-	if video.hwDebugContext {
-		glfw.WindowHint(glfw.OpenGLDebugContext, glfw.True)
-	}
-}
-
 // SetShouldClose sets the value of the close flag of the window.
 func (video *Video) SetShouldClose(b bool) {
 	if video.Window == nil {
@@ -339,85 +92,37 @@ func panicOnErr(v uint32, err error) uint32 {
 	return v
 }
 
-func (video *Video) ensurePixelFormatDefaults() {
-	if video.pixFmt == 0 {
-		video.pixFmt = gl.UNSIGNED_SHORT_5_5_5_1
-		video.pixType = gl.BGRA
-		video.bpp = 2
-	}
-}
-
-func (video *Video) resetGameTexture(width, height int32) {
-	if width < 1 {
-		width = 1
-	}
-	if height < 1 {
-		height = 1
-	}
-
-	if video.texID != 0 {
-		gl.DeleteTextures(1, &video.texID)
-		video.texID = 0
-	}
-
-	gl.GenTextures(1, &video.texID)
-	gl.ActiveTexture(gl.TEXTURE0)
-	gl.BindTexture(gl.TEXTURE_2D, video.texID)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
-	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, width, height, 0, video.pixType, video.pixFmt, nil)
-	video.texWidth = width
-	video.texHeight = height
-}
-
 // Configure instanciates the video package
 func (video *Video) Configure(fullscreen bool) {
-	if err := video.configureWithSize(384*2, 240*2, fullscreen); err != nil {
+	var width, height int
+	var m *glfw.Monitor
+
+	if fullscreen {
+		m = glfw.GetMonitors()[settings.Current.VideoMonitorIndex]
+		vms := m.GetVideoModes()
+		vm := vms[len(vms)-1]
+		width = vm.Width
+		height = vm.Height
+	} else {
+		width = 384 * 2
+		height = 240 * 2
+	}
+
+	var err error
+	video.Window, err = glfw.CreateWindow(width, height, "Ludo", m, nil)
+	if err != nil {
 		panic("Window creation failed:" + err.Error())
 	}
-}
 
-func (video *Video) configureWithSize(width, height int, fullscreen bool) error {
-	if fullscreen && video.windowedWidth != 0 {
-		width, height = video.windowedWidth, video.windowedHeight
-	}
-	video.configureWindowHints()
-	window, err := glfw.CreateWindow(width, height, video.title, nil, nil)
-	if err != nil {
-		return err
-	}
-	// GLFW may report a platform error without returning it through the Go binding.
-	if window == nil {
-		return errors.New("window creation failed")
-	}
-
-	// Keep the old context and its resources until the replacement exists.
-	if video.Window != nil {
-		video.RunContextDestroy()
-		video.DestroySharedHWContext()
-		video.Window.Destroy()
-	}
-	video.Window = window
-
-	// Object names from the old share group must not be reused in this context.
-	video.texID = 0
-	video.cachedFrameTexID = 0
-	video.cachedFrameW, video.cachedFrameH = 0, 0
-	video.cachedFrameValid = false
-	video.width, video.height = 0, 0
-	video.data = nil
-	video.needUpload = false
 	video.Window.MakeContextCurrent()
 
 	// Force a minimum size for the window.
 	video.Window.SetSizeLimits(160, 120, glfw.DontCare, glfw.DontCare)
-	video.SetFullscreen(fullscreen)
 
 	video.Window.SetInputMode(glfw.CursorMode, glfw.CursorHidden)
 
-	if err := initGL(); err != nil {
+	// Initialize Glow
+	if err := gl.Init(); err != nil {
 		panic(err)
 	}
 
@@ -447,9 +152,8 @@ func (video *Video) configureWithSize(width, height int, fullscreen bool) error
 	video.borderProgram = panicOnErr(newProgram(vertexShader, borderFragmentShader))
 	video.circleProgram = panicOnErr(newProgram(vertexShader, circleFragmentShader))
 
-	video.program = video.defaultProgram
+	video.UpdateFilter(settings.Current.VideoFilter)
 
-	gl.UseProgram(video.program)
 	textureUniform := gl.GetUniformLocation(video.program, gl.Str("Texture\x00"))
 	gl.Uniform1i(textureUniform, 0)
 
@@ -470,33 +174,28 @@ func (video *Video) configureWithSize(width, height int, fullscreen bool) error
 	gl.VertexAttribPointerWithOffset(texCoordAttrib, 2, gl.FLOAT, false, 4*4, 2*4)
 
 	// Some cores won't call SetPixelFormat, provide default values
-	video.ensurePixelFormatDefaults()
-
-	if video.Geom.MaxWidth == 0 || video.Geom.MaxHeight == 0 {
-		video.Geom.MaxWidth = video.Geom.BaseWidth
-		video.Geom.MaxHeight = video.Geom.BaseHeight
+	if video.pixFmt == 0 {
+		video.pixFmt = gl.UNSIGNED_SHORT_5_5_5_1
+		video.pixType = gl.BGRA
+		video.bpp = 2
 	}
 
-	video.texWidth = int32(video.Geom.MaxWidth)
-	video.texHeight = int32(video.Geom.MaxHeight)
-	if video.texWidth < 1 {
-		video.texWidth = 1
+	gl.GenTextures(1, &video.texID)
+
+	gl.ActiveTexture(gl.TEXTURE0)
+	if video.texID == 0 && state.Verbose {
+		log.Println("[Video]: Failed to create the vid texture")
 	}
-	if video.texHeight < 1 {
-		video.texHeight = 1
-	}
-	video.resetGameTexture(video.texWidth, video.texHeight)
+
+	gl.BindTexture(gl.TEXTURE_2D, video.texID)
 
 	video.UpdateFilter(settings.Current.VideoFilter)
 
-	video.coreRatioViewport(fbw, fbh, video.Geom.BaseWidth, video.Geom.BaseHeight)
+	video.coreRatioViewport(fbw, fbh)
 
-	bindVertexArray(0)
-
-	for e := gl.GetError(); e != gl.NO_ERROR; e = gl.NO_ERROR {
+	if e := gl.GetError(); e != gl.NO_ERROR {
 		log.Printf("[Video] OpenGL error: %d\n", e)
 	}
-	return nil
 }
 
 // UpdateFilter configures the game texture filter and shader. We currently
@@ -507,7 +206,6 @@ func (video *Video) configureWithSize(width, height int, fullscreen bool) error
 // CRT: zfast-crt
 // LCD: zfast-lcd
 func (video *Video) UpdateFilter(filter string) {
-	gl.ActiveTexture(gl.TEXTURE0)
 	gl.BindTexture(gl.TEXTURE_2D, video.texID)
 	switch filter {
 	case "Smooth":
@@ -536,9 +234,8 @@ func (video *Video) UpdateFilter(filter string) {
 	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
 	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
 	gl.UseProgram(video.program)
-	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("TextureSize\x00")), float32(video.texWidth), float32(video.texHeight))
+	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("TextureSize\x00")), float32(video.width), float32(video.height))
 	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("InputSize\x00")), float32(video.width), float32(video.height))
-	gl.UseProgram(0)
 }
 
 // SetPixelFormat is a callback passed to the libretro implementation.
@@ -586,38 +283,9 @@ func (video *Video) ResetRot() {
 	video.rot = 0
 }
 
-// ResetCoreState clears per-core video state and destroys its GL context.
-func (video *Video) ResetCoreState() {
-	video.DestroySharedHWContext()
-	video.MakeFrontendContextCurrent()
-	libretro.SetCurrentFramebufferValue(0)
-	video.ResetPitch()
-	video.ResetRot()
-	video.needUpload = false
-	video.data = nil
-	video.width = 0
-	video.height = 0
-	video.pixFmt = 0
-	video.pixType = 0
-	video.bpp = 0
-	video.ensurePixelFormatDefaults()
-	if video.texID != 0 {
-		video.resetGameTexture(1, 1)
-		video.UpdateFilter(settings.Current.VideoFilter)
-	}
-	video.texWidth = 0
-	video.texHeight = 0
-	if video.cachedFrameTexID != 0 {
-		gl.DeleteTextures(1, &video.cachedFrameTexID)
-		video.cachedFrameTexID = 0
-	}
-	video.cachedFrameW = 0
-	video.cachedFrameH = 0
-	video.cachedFrameValid = false
-}
-
-// gameViewport fits the game to the framebuffer and records its screenshot bounds.
-func (video *Video) gameViewport(fbWidth, fbHeight int) (x, y, w, h float32) {
+// coreRatioViewport configures the vertex array to display the game at the center of the window
+// while preserving the original ascpect ratio of the game or core
+func (video *Video) coreRatioViewport(fbWidth int, fbHeight int) (x, y, w, h float32) {
 	// Scale the content to fit in the viewport.
 	fbw := float32(fbWidth)
 	fbh := float32(fbHeight)
@@ -635,36 +303,11 @@ func (video *Video) gameViewport(fbWidth, fbHeight int) (x, y, w, h float32) {
 		w = fbw
 	}
 
-	// Keep centered, pixel-aligned bounds so the cached copy needs no resampling.
-	x = float32(int32((fbw - w) / 2))
-	y = float32(int32((fbh - h) / 2))
-	w = fbw - 2*x
-	h = fbh - 2*y
-
-	video.presentX = int32(x)
-	video.presentY = int32(y)
-	video.presentW = int32(w)
-	video.presentH = int32(h)
-	return
-}
-
-// coreRatioViewport configures the game quad's placement and core texture coordinates.
-func (video *Video) coreRatioViewport(fbWidth, fbHeight, clipWidth, clipHeight int) (x, y, w, h float32) {
-	x, y, w, h = video.gameViewport(fbWidth, fbHeight)
-	va := vertexArrayForFramebuffer(x, y, w, h, 1.0, float32(fbWidth), float32(fbHeight))
-
-	if clipWidth == 0 {
-		clipWidth = int(video.texWidth)
-	}
-	if clipHeight == 0 {
-		clipHeight = int(video.texHeight)
-	}
-
-	va[3] = float32(clipHeight) / float32(video.texHeight)
-	va[10] = float32(clipWidth) / float32(video.texWidth)
-	va[11] = va[3]
-	va[14] = va[10]
+	// Place the content in the middle of the window.
+	x = (fbw - w) / 2
+	y = (fbh - h) / 2
 
+	va := video.vertexArray(x, y, w, h, 1.0)
 	va = rotateUV(va, video.rot)
 	gl.BindBuffer(gl.ARRAY_BUFFER, video.vbo)
 	gl.BufferData(gl.ARRAY_BUFFER, len(va)*4, gl.Ptr(va), gl.STATIC_DRAW)
@@ -672,29 +315,6 @@ func (video *Video) coreRatioViewport(fbWidth, fbHeight, clipWidth, clipHeight i
 	return
 }
 
-// BeginFrontendFrame sets the state used by Ludo's game quad and menu.
-// Core GL state lives in HWWindow and is never modified here.
-func (video *Video) BeginFrontendFrame() {
-	// Render directly to the screen.
-	bindBackbuffer()
-	gl.DrawBuffer(gl.BACK)
-	gl.ReadBuffer(gl.BACK)
-
-	// Establish a frontend-owned GL baseline before drawing the game quad/menu.
-	gl.Disable(gl.DEPTH_TEST)
-	gl.Disable(gl.CULL_FACE)
-	gl.Disable(gl.DITHER)
-	gl.Disable(gl.SCISSOR_TEST)
-	gl.Disable(gl.STENCIL_TEST)
-	gl.Disable(gl.BLEND)
-	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
-	gl.BlendEquation(gl.FUNC_ADD)
-	gl.ColorMask(true, true, true, true)
-	gl.DepthMask(true)
-
-	video.ResizeViewport()
-}
-
 // ResizeViewport resizes the GL viewport to the framebuffer size
 func (video *Video) ResizeViewport() {
 	fbw, fbh := video.Window.GetFramebufferSize()
@@ -710,156 +330,45 @@ func (video *Video) ResizeViewport() {
 	}
 }
 
-// Render draws the current game frame using the frontend context/state.
+// Render the current frame
 func (video *Video) Render() {
 	if !state.CoreRunning {
 		gl.ClearColor(1, 1, 1, 1)
 		gl.Clear(gl.COLOR_BUFFER_BIT)
 		return
 	}
-
 	gl.ClearColor(0, 0, 0, 1)
 	gl.Clear(gl.COLOR_BUFFER_BIT)
 
-	// Wait for a valid refresh, not merely an allocated HW framebuffer.
-	if video.width == 0 || video.height == 0 {
+	// Early return to not render the first frame of a newly loaded game with the
+	// previous game pitch. A sane pitch must be set by video.Refresh first.
+	if video.pitch == 0 {
 		return
 	}
 
 	video.uploadTexture()
 
 	fbw, fbh := video.Window.GetFramebufferSize()
-	_, _, w, h := video.coreRatioViewport(fbw, fbh, int(video.width), int(video.height))
+	_, _, w, h := video.coreRatioViewport(fbw, fbh)
 
 	gl.UseProgram(video.program)
-	if loc := gl.GetUniformLocation(video.program, gl.Str("color\x00")); loc >= 0 {
-		gl.Uniform4f(loc, 1, 1, 1, 1)
-	}
 	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("OutputSize\x00")), w, h)
 
-	if state.Core.HWRenderCallback != nil {
-		gl.UniformMatrix4fv(gl.GetUniformLocation(video.program, gl.Str("MVP\x00")), 1, false, &video.orthoMat[0])
-	}
+	bindVertexArray(video.vao)
 
-	gl.ActiveTexture(gl.TEXTURE0)
 	gl.BindTexture(gl.TEXTURE_2D, video.texID)
 	gl.BindBuffer(gl.ARRAY_BUFFER, video.vbo)
 
-	bindVertexArray(video.vao)
-	// Preserve opaque alpha even when the core leaves its alpha channel unset.
-	gl.ColorMask(true, true, true, false)
 	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
-	gl.ColorMask(true, true, true, true)
-	bindVertexArray(0)
-
-	// Reset MVP to identity to avoid menu issues
-	gl.UniformMatrix4fv(gl.GetUniformLocation(video.program, gl.Str("MVP\x00")), 1, false, &video.identityMat[0])
-	gl.UseProgram(0)
-}
-
-func (video *Video) ensureCachedFrameTexture(width, height int32) {
-	if width < 1 || height < 1 {
-		return
-	}
-
-	if video.cachedFrameTexID == 0 {
-		gl.GenTextures(1, &video.cachedFrameTexID)
-	}
-
-	gl.ActiveTexture(gl.TEXTURE0)
-	gl.BindTexture(gl.TEXTURE_2D, video.cachedFrameTexID)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
-
-	if video.cachedFrameW != width || video.cachedFrameH != height {
-		gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, width, height, 0, gl.RGBA, gl.UNSIGNED_BYTE, nil)
-		video.cachedFrameW = width
-		video.cachedFrameH = height
-	}
-}
-
-// CachePresentedFrame copies the game rectangle, without borders or UI, so menu-mode
-// rendering does not depend on the core keeping its paused framebuffer alive.
-func (video *Video) CachePresentedFrame() {
-	if !state.CoreRunning || video.width == 0 || video.height == 0 {
-		video.cachedFrameValid = false
-		return
-	}
-
-	if video.presentW < 1 || video.presentH < 1 {
-		video.cachedFrameValid = false
-		return
-	}
-
-	video.ensureCachedFrameTexture(video.presentW, video.presentH)
-	if video.cachedFrameTexID == 0 {
-		video.cachedFrameValid = false
-		return
-	}
-
-	gl.ActiveTexture(gl.TEXTURE0)
-	gl.BindTexture(gl.TEXTURE_2D, video.cachedFrameTexID)
-	gl.CopyTexSubImage2D(gl.TEXTURE_2D, 0, 0, 0, video.presentX, video.presentY, video.presentW, video.presentH)
-	video.cachedFrameValid = true
-}
-
-// RenderCachedFrame draws the last cached frontend-presented game frame.
-func (video *Video) RenderCachedFrame() bool {
-	if !video.cachedFrameValid || video.cachedFrameTexID == 0 || video.cachedFrameW < 1 || video.cachedFrameH < 1 {
-		return false
-	}
-
-	gl.ClearColor(0, 0, 0, 1)
-	gl.Clear(gl.COLOR_BUFFER_BIT)
-
-	fbw, fbh := video.Window.GetFramebufferSize()
-	x, y, w, h := video.gameViewport(fbw, fbh)
-	va := vertexArrayForFramebuffer(x, y, w, h, 1.0, float32(fbw), float32(fbh))
-	// A backbuffer copy always has bottom-left origin, regardless of the core.
-	va[3] = 0
-	va[7] = 1
-	va[11] = 0
-	va[15] = 1
-	gl.BindBuffer(gl.ARRAY_BUFFER, video.vbo)
-	gl.BufferData(gl.ARRAY_BUFFER, len(va)*4, gl.Ptr(va), gl.STATIC_DRAW)
-
-	gl.UseProgram(video.defaultProgram)
-	gl.Uniform4f(gl.GetUniformLocation(video.defaultProgram, gl.Str("color\x00")), 1, 1, 1, 1)
-	gl.Uniform2f(gl.GetUniformLocation(video.defaultProgram, gl.Str("OutputSize\x00")), w, h)
-	gl.Uniform2f(gl.GetUniformLocation(video.defaultProgram, gl.Str("TextureSize\x00")), float32(video.cachedFrameW), float32(video.cachedFrameH))
-	gl.Uniform2f(gl.GetUniformLocation(video.defaultProgram, gl.Str("InputSize\x00")), float32(video.cachedFrameW), float32(video.cachedFrameH))
-
-	gl.ActiveTexture(gl.TEXTURE0)
-	gl.BindTexture(gl.TEXTURE_2D, video.cachedFrameTexID)
-	bindVertexArray(video.vao)
-	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
-	bindVertexArray(0)
-	gl.UseProgram(0)
-	return true
-}
-
-// RenderPresentedFrame redraws the current game image for menu-mode frontend
-// rendering, preferring the cached last-good frame when available.
-func (video *Video) RenderPresentedFrame() {
-	if !video.RenderCachedFrame() {
-		video.Render()
-		video.CachePresentedFrame()
-	}
 }
 
 // Refresh the texture framebuffer
 func (video *Video) Refresh(data unsafe.Pointer, width int32, height int32, pitch int32) {
-	// NULL duplicates the last frame; its dimensions need not be supplied.
-	if data == nil {
-		return
-	}
 	video.needUpload = true
 	video.width = width
 	video.height = height
 	video.pitch = pitch
-	video.data = data
+	video.data = data // maybe need a full copy
 }
 
 func (video *Video) uploadTexture() {
@@ -869,29 +378,13 @@ func (video *Video) uploadTexture() {
 
 	gl.ActiveTexture(gl.TEXTURE0)
 	gl.BindTexture(gl.TEXTURE_2D, video.texID)
-
-	if video.data != libretro.HWFrameBufferValid {
-		video.texWidth = video.width
-		video.texHeight = video.height
-		gl.PixelStorei(gl.UNPACK_ROW_LENGTH, video.pitch/video.bpp)
-		gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, video.texWidth, video.texHeight, 0, video.pixType, video.pixFmt, video.data)
-	}
+	gl.PixelStorei(gl.UNPACK_ROW_LENGTH, video.pitch/video.bpp)
 
 	gl.UseProgram(video.program)
-	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("TextureSize\x00")), float32(video.texWidth), float32(video.texHeight))
+	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("TextureSize\x00")), float32(video.width), float32(video.height))
 	gl.Uniform2f(gl.GetUniformLocation(video.program, gl.Str("InputSize\x00")), float32(video.width), float32(video.height))
-	gl.UseProgram(0)
-	video.needUpload = false
-}
 
-// CurrentFramebuffer returns the current FBO ID
-func (video *Video) CurrentFramebuffer() uintptr {
-	return uintptr(video.fboID)
-}
-
-// ProcAddress returns the address of the proc from GLFW
-func (video *Video) ProcAddress(procName string) uintptr {
-	return uintptr(glfw.GetProcAddress(procName))
+	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, video.width, video.height, 0, video.pixType, video.pixFmt, video.data)
 }
 
 // SetRotation rotates the game image as requested by the core

video/video_darwin.go

@@ -0,0 +1,15 @@
+// +build darwin
+
+package video
+
+import (
+	"github.com/go-gl/gl/v2.1/gl"
+)
+
+func genVertexArrays(n int32, arrays *uint32) {
+	gl.GenVertexArraysAPPLE(n, arrays)
+}
+
+func bindVertexArray(array uint32) {
+	gl.BindVertexArrayAPPLE(array)
+}

video/video_notdarwin.go

@@ -0,0 +1,15 @@
+// +build !darwin
+
+package video
+
+import (
+	"github.com/go-gl/gl/v2.1/gl"
+)
+
+func genVertexArrays(n int32, arrays *uint32) {
+	gl.GenVertexArrays(n, arrays)
+}
+
+func bindVertexArray(array uint32) {
+	gl.BindVertexArray(array)
+}