From 1a8369e51c30b8f4486e32c819f890f011adc637 Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Mon, 26 May 2014 11:40:46 -0700
Subject: [PATCH] Apply a very specific hack for Danganronpa.

This should allow playing at non-1x resolutions, and without slowing down
the entire game just for one small framebuffer.

Generally, hacks are a bad thing.  But even with memcpy and block transfer
stuff, we'll never be able to solve this game without some sort of hack.
Detecting memory reads will complicate cross-platform compat or slow
things down.
---
 GPU/GLES/Framebuffer.cpp | 22 +++++++++++++++++++---
 GPU/GLES/Framebuffer.h   |  3 +++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/GPU/GLES/Framebuffer.cpp b/GPU/GLES/Framebuffer.cpp
index dd31e3fd8..ad6119e7d 100644
--- a/GPU/GLES/Framebuffer.cpp
+++ b/GPU/GLES/Framebuffer.cpp
@@ -30,6 +30,7 @@
 #include "Core/Config.h"
 #include "Core/System.h"
 #include "Core/Reporting.h"
+#include "Core/ELF/ParamSFO.h"
 #include "Core/HLE/sceDisplay.h"
 #include "GPU/ge_constants.h"
 #include "GPU/GPUState.h"
@@ -344,7 +345,13 @@ FramebufferManager::FramebufferManager() :
 
 	useBufferedRendering_ = g_Config.iRenderingMode != FB_NON_BUFFERED_MODE;
 	updateVRAM_ = !(g_Config.iRenderingMode == FB_NON_BUFFERED_MODE || g_Config.iRenderingMode == FB_BUFFERED_MODE);
-	
+
+	const std::string gameId = g_paramSFO.GetValueString("DISC_ID");
+	// This applies a hack to Dangan Ronpa, its demo, and its sequel.
+	// The game draws solid colors to a small framebuffer, and then reads this directly in VRAM.
+	// We force this framebuffer to 1x and force download it automatically.
+	hackForce04154000Download_ = gameId == "NPJH50631" || gameId == "NPJH50372" || gameId == "NPJH90164";
+
 	SetLineWidth();
 }
 
@@ -770,6 +777,11 @@ void FramebufferManager::DoSetRenderFrameBuffer() {
 	float renderWidthFactor = (float)PSP_CoreParameter().renderWidth / 480.0f;
 	float renderHeightFactor = (float)PSP_CoreParameter().renderHeight / 272.0f;
 
+	if (hackForce04154000Download_ && MaskedEqual(fb_address, 0x04154000)) {
+		renderWidthFactor = 1.0;
+		renderHeightFactor = 1.0;
+	}
+
 	// None found? Create one.
 	if (!vfb) {
 		gstate_c.textureChanged |= TEXCHANGE_PARAMSONLY;
@@ -873,7 +885,7 @@ void FramebufferManager::DoSetRenderFrameBuffer() {
 	// We already have it!
 	} else if (vfb != currentRenderVfb_) {
 	
-		if (updateVRAM_ && !vfb->memoryUpdated) {
+		if (ShouldDownloadFramebuffer(vfb) && !vfb->memoryUpdated) {
 			ReadFramebufferToMemory(vfb, true, 0, 0, vfb->width, vfb->height);
 		}
 		// Use it as a render target.
@@ -1145,6 +1157,10 @@ void FramebufferManager::CopyDisplayToOutput() {
 	}
 }
 
+inline bool FramebufferManager::ShouldDownloadFramebuffer(const VirtualFramebuffer *vfb) const {
+	return updateVRAM_ || (hackForce04154000Download_ && MaskedEqual(vfb->fb_address, 0x04154000));
+}
+
 void FramebufferManager::ReadFramebufferToMemory(VirtualFramebuffer *vfb, bool sync, int x, int y, int w, int h) {
 
 #ifndef USING_GLES2
@@ -1736,7 +1752,7 @@ void FramebufferManager::DecimateFBOs() {
 		VirtualFramebuffer *vfb = vfbs_[i];
 		int age = frameLastFramebufUsed - std::max(vfb->last_frame_render, vfb->last_frame_used);
 
-		if (updateVRAM_ && age == 0 && !vfb->memoryUpdated) {
+		if (ShouldDownloadFramebuffer(vfb) && age == 0 && !vfb->memoryUpdated) {
 #ifdef USING_GLES2
 			bool sync = true;
 #else
diff --git a/GPU/GLES/Framebuffer.h b/GPU/GLES/Framebuffer.h
index e23ae84cd..3eef9aef3 100644
--- a/GPU/GLES/Framebuffer.h
+++ b/GPU/GLES/Framebuffer.h
@@ -209,6 +209,7 @@ public:
 		}
 		return true;
 	}
+	inline bool ShouldDownloadFramebuffer(const VirtualFramebuffer *vfb) const;
 
 	bool NotifyFramebufferCopy(u32 src, u32 dest, int size);
 
@@ -274,6 +275,8 @@ private:
 	bool updateVRAM_;
 	bool gameUsesSequentialCopies_;
 
+	bool hackForce04154000Download_;
+
 	// The range of PSP memory that may contain FBOs.  So we can skip iterating.
 	u32 framebufRangeEnd_;