Add stereoscopic feature to 3DS

3ds/gfx/gfx.t3s

@@ -5,6 +5,7 @@ battery2.png
 battery3.png
 battery4.png
 batteryCharge.png
+bubble.png
 c3dlogo.png
 wifiNull.png
 wifi1.png

CMakeLists.txt

@@ -214,7 +214,7 @@ elseif(NINTENDO_3DS)
 	endif()
 
 	target_compile_definitions(${FTPD_TARGET} PRIVATE
-		ANTI_ALIAS=1
+		ANTI_ALIAS=0
 	)
 
 	find_package(PkgConfig REQUIRED)
@@ -250,6 +250,7 @@ elseif(NINTENDO_3DS)
 			3ds/gfx/battery3.png
 			3ds/gfx/battery4.png
 			3ds/gfx/batteryCharge.png
+			3ds/gfx/bubble.png
 			3ds/gfx/c3dlogo.png
 			3ds/gfx/wifi1.png
 			3ds/gfx/wifi2.png

source/3ds/imgui_citro3d.cpp

@@ -5,7 +5,7 @@
 //
 // The MIT License (MIT)
 //
-// Copyright (C) 2023 Michael Theall
+// Copyright (C) 2024 Michael Theall
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -35,6 +35,7 @@
 #include "imgui.h"
 
 #include <algorithm>
+#include <bit>
 #include <cstdint>
 #include <cstdlib>
 #include <cstring>
@@ -42,6 +43,13 @@
 
 namespace
 {
+/// \brief Slider value
+float s_slider;
+/// \brief Z offset (for stereoscopic effect)
+float s_z;
+/// \brief Z offset uniform location
+int s_zLocation;
+
 /// \brief 3DS font glyph ranges
 std::vector<ImWchar> s_fontRanges;
 
@@ -175,6 +183,9 @@ void imgui::citro3d::init ()
 	shaderProgramInit (&s_program);
 	shaderProgramSetVsh (&s_program, &s_vsh->DVLE[0]);
 
+	// get projection matrix uniform location
+	s_zLocation = shaderInstanceGetUniformLocation (s_program.vertexShader, "z");
+
 	// get projection matrix uniform location
 	s_projLocation = shaderInstanceGetUniformLocation (s_program.vertexShader, "proj");
 
@@ -417,7 +428,9 @@ void imgui::citro3d::exit ()
 	DVLB_Free (s_vsh);
 }
 
-void imgui::citro3d::render (C3D_RenderTarget *const top_, C3D_RenderTarget *const bottom_)
+void imgui::citro3d::render (C3D_RenderTarget *const topLeft_,
+    C3D_RenderTarget *const topRight_,
+    C3D_RenderTarget *const bottom_)
 {
 	// get draw data
 	auto const drawData = ImGui::GetDrawData ();
@@ -497,12 +510,27 @@ void imgui::citro3d::render (C3D_RenderTarget *const top_, C3D_RenderTarget *con
 		offsetIdx += cmdList.IdxBuffer.Size;
 	}
 
-	for (auto const &screen : {GFX_TOP, GFX_BOTTOM})
+	auto const slider = osGet3DSliderState ();
+
+	for (auto const &[target, screen, side] : {
+	         // clang-format off
+	         std::make_tuple (topLeft_, GFX_TOP, GFX_LEFT),
+	         std::make_tuple (slider ? topRight_ : nullptr, GFX_TOP, GFX_RIGHT),
+	         std::make_tuple (bottom_, GFX_BOTTOM, GFX_LEFT)
+	         // clang-format on
+	     })
 	{
-		if (screen == GFX_TOP)
+		if (!target)
-			C3D_FrameDrawOn (top_);
+			continue;
+
+		if (target == topLeft_)
+			s_slider = slider;
+		else if (target == topRight_)
+			s_slider = -slider;
 		else
-			C3D_FrameDrawOn (bottom_);
+			s_slider = 0.0f;
+
+		C3D_FrameDrawOn (target);
 
 		setupRenderState (screen);
 
@@ -534,14 +562,24 @@ void imgui::citro3d::render (C3D_RenderTarget *const top_, C3D_RenderTarget *con
 					clip.z = (cmd.ClipRect.z - clipOff.x) * clipScale.x;
 					clip.w = (cmd.ClipRect.w - clipOff.y) * clipScale.y;
 
+					if (s_slider && s_z && screen == GFX_TOP)
+					{
+						clip.x -= s_slider * s_z;
+						clip.z += s_slider * s_z;
+					}
+
 					if (clip.x >= width || clip.y >= height || clip.z < 0.0f || clip.w < 0.0f)
 						continue;
+
 					if (clip.x < 0.0f)
 						clip.x = 0.0f;
+
 					if (clip.y < 0.0f)
 						clip.y = 0.0f;
+
 					if (clip.z > width)
 						clip.z = width;
+
 					if (clip.w > height)
 						clip.z = height;
 
@@ -732,4 +770,13 @@ void imgui::citro3d::render (C3D_RenderTarget *const top_, C3D_RenderTarget *con
 		}
 	}
 }
+
+void imgui::citro3d::setZ (ImDrawList const *const drawList_, ImDrawCmd const *const drawCmd_)
+{
+	(void)drawList_;
+
+	s_z = std::bit_cast<float> (drawCmd_->UserCallbackData);
+
+	C3D_FVUnifSet (GPU_VERTEX_SHADER, s_zLocation, s_slider * s_z, 0.0f, 0.0f, 0.0f);
+}
 #endif

source/3ds/imgui_citro3d.h

@@ -5,7 +5,7 @@
 //
 // The MIT License (MIT)
 //
-// Copyright (C) 2020 Michael Theall
+// Copyright (C) 2024 Michael Theall
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -30,6 +30,9 @@
 #ifndef CLASSIC
 #include <citro3d.h>
 
+struct ImDrawList;
+struct ImDrawCmd;
+
 namespace imgui
 {
 namespace citro3d
@@ -40,7 +43,15 @@ void init ();
 void exit ();
 
 /// \brief Render ImGui draw list
-void render (C3D_RenderTarget *top_, C3D_RenderTarget *bottom_);
+/// \param topLeft_ Top left render target
+/// \param topRight_ Top right render target (skipped if not stereoscopic)
+/// \param bottom_ Bottom render target
+void render (C3D_RenderTarget *topLeft_, C3D_RenderTarget *topRight_, C3D_RenderTarget *bottom_);
+
+/// \brief Set Z offset (for stereoscopic effect)
+/// \param drawList_ Draw list
+/// \param drawCmd_ Draw command
+void setZ (ImDrawList const *drawList_, ImDrawCmd const *drawCmd_);
 }
 }
 #endif

source/3ds/platform.cpp

@@ -39,12 +39,15 @@
 #include <arpa/inet.h>
 #include <malloc.h>
 
+#include <algorithm>
 #include <atomic>
 #include <cassert>
 #include <chrono>
 #include <cstring>
 #include <ctime>
 #include <mutex>
+#include <random>
+#include <vector>
 
 #ifdef CLASSIC
 PrintConsole g_statusConsole;
@@ -116,8 +119,10 @@ constexpr auto DISPLAY_TRANSFER_FLAGS =
     GX_TRANSFER_IN_FORMAT (GX_TRANSFER_FMT_RGBA8) | GX_TRANSFER_OUT_FORMAT (GX_TRANSFER_FMT_RGB8) |
     GX_TRANSFER_SCALING (TRANSFER_SCALING);
 
-/// \brief Top screen render target
+/// \brief Top left screen render target
-C3D_RenderTarget *s_top = nullptr;
+C3D_RenderTarget *s_topLeft = nullptr;
+/// \brief Top right screen render target
+C3D_RenderTarget *s_topRight = nullptr;
 /// \brief Bottom screen render target
 C3D_RenderTarget *s_bottom = nullptr;
 
@@ -271,12 +276,15 @@ void drawLogo ()
 	auto const uv1 = ImVec2 (subTex->left, subTex->top);
 	auto const uv2 = ImVec2 (subTex->right, subTex->bottom);
 
+	auto const drawList = ImGui::GetBackgroundDrawList ();
+
 	// draw to top screen
-	ImGui::GetBackgroundDrawList ()->AddImage (
+	drawList->AddCallback (&imgui::citro3d::setZ, std::bit_cast<void *> (-5.0f));
-	    &s_gfxTexture, ImVec2 (x1, y1), ImVec2 (x2, y2), uv1, uv2);
+	drawList->AddImage (&s_gfxTexture, ImVec2 (x1, y1), ImVec2 (x2, y2), uv1, uv2);
+	drawList->AddCallback (&imgui::citro3d::setZ, std::bit_cast<void *> (0.0f));
 
 	// draw to bottom screen
-	ImGui::GetBackgroundDrawList ()->AddImage (&s_gfxTexture,
+	drawList->AddImage (&s_gfxTexture,
 	    ImVec2 (x1, y1 + screenHeight * 0.5f),
 	    ImVec2 (x2, y2 + screenHeight * 0.5f),
 	    uv1,
@@ -284,6 +292,94 @@ void drawLogo ()
 #endif
 }
 
+#ifndef CLASSIC
+struct Bubble
+{
+	float x;
+	float y;
+	float z;
+	float scale;
+	float dy;
+};
+
+std::vector<Bubble> &getBubbles ()
+{
+	static std::vector<Bubble> bubbles;
+
+	if (!bubbles.empty ())
+		return bubbles;
+
+	auto eng  = std::default_random_engine (std::random_device{}());
+	auto dist = std::uniform_real_distribution<float> (0.0f, 1.0f);
+
+	constexpr auto COUNT = 250;
+
+	bubbles.reserve (COUNT);
+	for (unsigned i = 0; i < COUNT; ++i)
+	{
+		auto &bubble = bubbles.emplace_back ();
+
+		bubble.x     = 500.0f * dist (eng) - 50.0f;
+		bubble.y     = 240.0f * dist (eng);
+		bubble.z     = std::floor (-5.0f * dist (eng));
+		bubble.scale = std::max (dist (eng) / 8.0f, 0.0625f);
+		bubble.dy    = std::max (1.5f * dist (eng), 0.25f);
+	}
+
+	std::ranges::sort (
+	    bubbles, [] (auto const &lhs_, auto const &rhs_) { return lhs_.z < rhs_.z; });
+
+	return bubbles;
+}
+#endif
+
+void drawBubbles ()
+{
+#ifndef CLASSIC
+	// only draw in stereoscopy
+	if (!osGet3DSliderState ())
+		return;
+
+	auto const &io = ImGui::GetIO ();
+
+	auto const screenHeight = io.DisplaySize.y / 2.0f;
+
+	auto const tex = Tex3DS_GetSubTexture (s_gfxT3x, gfx_bubble_idx);
+
+	auto const uv1 = ImVec2 (tex->left, tex->top);
+	auto const uv2 = ImVec2 (tex->right, tex->bottom);
+
+	float lastZ = 0.0f;
+
+	auto const drawList = ImGui::GetBackgroundDrawList ();
+	for (auto &bubble : getBubbles ())
+	{
+		if (bubble.z != lastZ)
+		{
+			lastZ = bubble.z;
+			drawList->AddCallback (&imgui::citro3d::setZ, std::bit_cast<void *> (lastZ));
+		}
+
+		bubble.y -= bubble.dy;
+
+		if (bubble.y < 0.0f)
+			bubble.y = screenHeight;
+
+		auto const width  = bubble.scale * tex->width;
+		auto const height = bubble.scale * tex->height;
+
+		auto const p1 = ImVec2 (
+		    bubble.x + 100.0f * bubble.scale * std::sin (bubble.z + bubble.y / 40.0f), bubble.y);
+		auto const p2 = ImVec2 (p1.x + width, p1.y + height);
+
+		drawList->AddImage (&s_gfxTexture, p1, p2, uv1, uv2);
+	}
+
+	if (lastZ != 0.0f)
+		drawList->AddCallback (&imgui::citro3d::setZ, std::bit_cast<void *> (0.0f));
+#endif
+}
+
 /// \brief Draw status
 void drawStatus ()
 {
@@ -389,9 +485,10 @@ bool platform::init ()
 	romfsInit ();
 #endif
 	gfxInitDefault ();
-	gfxSet3D (false);
 
 #ifdef CLASSIC
+	gfxSet3D (false);
+
 	consoleInit (GFX_TOP, &g_statusConsole);
 	consoleInit (GFX_TOP, &g_logConsole);
 	consoleInit (GFX_BOTTOM, &g_sessionConsole);
@@ -399,6 +496,8 @@ bool platform::init ()
 	consoleSetWindow (&g_statusConsole, 0, 0, 50, 1);
 	consoleSetWindow (&g_logConsole, 0, 1, 50, 29);
 	consoleSetWindow (&g_sessionConsole, 0, 0, 40, 30);
+#else
+	gfxSet3D (true);
 #endif
 
 #ifndef NDEBUG
@@ -410,12 +509,17 @@ bool platform::init ()
 
 #ifndef CLASSIC
 	// initialize citro3d
-	C3D_Init (2 * C3D_DEFAULT_CMDBUF_SIZE);
+	C3D_Init (4 * C3D_DEFAULT_CMDBUF_SIZE);
 
-	// create top screen render target
+	// create top left screen render target
-	s_top =
+	s_topLeft =
 	    C3D_RenderTargetCreate (FB_HEIGHT * 0.5f, FB_WIDTH, GPU_RB_RGBA8, GPU_RB_DEPTH24_STENCIL8);
-	C3D_RenderTargetSetOutput (s_top, GFX_TOP, GFX_LEFT, DISPLAY_TRANSFER_FLAGS);
+	C3D_RenderTargetSetOutput (s_topLeft, GFX_TOP, GFX_LEFT, DISPLAY_TRANSFER_FLAGS);
+
+	// create top right screen render target
+	s_topRight =
+	    C3D_RenderTargetCreate (FB_HEIGHT * 0.5f, FB_WIDTH, GPU_RB_RGBA8, GPU_RB_DEPTH24_STENCIL8);
+	C3D_RenderTargetSetOutput (s_topRight, GFX_TOP, GFX_RIGHT, DISPLAY_TRANSFER_FLAGS);
 
 	// create bottom screen render target
 	s_bottom = C3D_RenderTargetCreate (
@@ -530,6 +634,7 @@ bool platform::loop ()
 void platform::render ()
 {
 	drawLogo ();
+	drawBubbles ();
 	drawStatus ();
 
 #ifdef CLASSIC
@@ -542,10 +647,11 @@ void platform::render ()
 	C3D_FrameBegin (C3D_FRAME_SYNCDRAW);
 
 	// clear frame/depth buffers
-	C3D_RenderTargetClear (s_top, C3D_CLEAR_ALL, CLEAR_COLOR, 0);
+	C3D_RenderTargetClear (s_topLeft, C3D_CLEAR_ALL, CLEAR_COLOR, 0);
+	C3D_RenderTargetClear (s_topRight, C3D_CLEAR_ALL, CLEAR_COLOR, 0);
 	C3D_RenderTargetClear (s_bottom, C3D_CLEAR_ALL, CLEAR_COLOR, 0);
 
-	imgui::citro3d::render (s_top, s_bottom);
+	imgui::citro3d::render (s_topLeft, s_topRight, s_bottom);
 
 	C3D_FrameEnd (0);
 #endif
@@ -562,7 +668,8 @@ void platform::exit ()
 
 	// free render targets
 	C3D_RenderTargetDelete (s_bottom);
-	C3D_RenderTargetDelete (s_top);
+	C3D_RenderTargetDelete (s_topRight);
+	C3D_RenderTargetDelete (s_topLeft);
 
 	// deinitialize citro3d
 	C3D_Fini ();

source/3ds/vshader.v.pica

@@ -3,7 +3,7 @@
 ; - RFC 3659 (https://tools.ietf.org/html/rfc3659)
 ; - suggested implementation details from https://cr.yp.to/ftp/filesystem.html
 ; 
-; Copyright (C) 2020 Michael Theall
+; Copyright (C) 2024 Michael Theall
 ; 
 ; This program is free software: you can redistribute it and/or modify
 ; it under the terms of the GNU General Public License as published by
@@ -23,6 +23,7 @@
 ; uniforms
 ; Projection matrix
 .fvec proj[4]
+.fvec z
 
 ; constants
 ; [1.0, 0.0, 1.0/255.0, 0.0]
@@ -43,6 +44,9 @@
 	mov r0.xy, inPos.xy
 	mov r0.zw, constants.yx
 
+	; offset stereoscopy
+	add r0.x, z.x, r0.x
+
 	; outPos = proj * inPos
 	dp4 outPos.x, proj[0], r0
 	dp4 outPos.y, proj[1], r0