OpenGL renderer support in melonDS!

waterbox/melon/BizGLPresenter.cpp

@@ -0,0 +1,207 @@
+#include "GPU.h"
+#include "OpenGLSupport.h"
+#include "frontend/FrontendUtil.h"
+
+#include "BizGLPresenter.h"
+
+#include <emulibc.h>
+
+// half of this is taken from melonDS/src/frontend/qt_sdl/main.cpp
+
+namespace GLPresenter
+{
+
+static const char* VertexShader = R"(#version 140
+
+uniform vec2 uSize;
+uniform mat2x3 uTransform;
+
+in vec2 vPosition;
+in vec2 vTexcoord;
+
+smooth out vec2 fTexcoord;
+
+void main()
+{
+	vec4 fpos;
+
+	fpos.xy = vec3(vPosition, 1.0) * uTransform;
+
+	fpos.xy = ((fpos.xy * 2.0) / uSize) - 1.0;
+	// fpos.y *= -1;
+	fpos.z = 0.0;
+	fpos.w = 1.0;
+
+	gl_Position = fpos;
+	fTexcoord = vTexcoord;
+}
+)";
+
+static const char* FragmentShader = R"(#version 140
+
+uniform sampler2D Tex;
+
+smooth in vec2 fTexcoord;
+
+out vec4 oColor;
+
+void main()
+{
+	vec4 pixel = texture(Tex, fTexcoord);
+
+	oColor = vec4(pixel.bgr, 1.0);
+}
+)";
+
+
+ECL_INVISIBLE static GLuint ShaderProgram[3];
+ECL_INVISIBLE static GLuint ShaderTransformULoc, ShaderSizeULoc;
+
+ECL_INVISIBLE static GLuint VertexBuffer, VertexArray;
+
+ECL_INVISIBLE static float TransformMatrix[2 * 6];
+
+ECL_INVISIBLE static u32 Width, Height;
+
+ECL_INVISIBLE static GLuint TextureID;
+ECL_INVISIBLE static GLuint FboID;
+ECL_INVISIBLE static GLuint PboID;
+
+void Init(u32 scale)
+{
+	Width = 256 * scale;
+	Height = 384 * scale;
+
+	OpenGL::BuildShaderProgram(VertexShader, FragmentShader, ShaderProgram, "GLPresenterShader");
+
+	GLuint pid = ShaderProgram[2];
+	glBindAttribLocation(pid, 0, "vPosition");
+	glBindAttribLocation(pid, 1, "vTexcoord");
+	glBindFragDataLocation(pid, 0, "oColor");
+
+	OpenGL::LinkShaderProgram(ShaderProgram);
+
+	glUseProgram(pid);
+	glUniform1i(glGetUniformLocation(pid, "Tex"), 0);
+
+	ShaderSizeULoc = glGetUniformLocation(pid, "uSize");
+	ShaderTransformULoc = glGetUniformLocation(pid, "uTransform");
+
+	constexpr int paddedHeight = 192 * 2 + 2;
+	constexpr float padPixels = 1.f / paddedHeight;
+
+	static const float vertices[] =
+	{
+		0.f,   0.f,    0.f, 0.f,
+		0.f,   192.f,  0.f, 0.5f - padPixels,
+		256.f, 192.f,  1.f, 0.5f - padPixels,
+		0.f,   0.f,    0.f, 0.f,
+		256.f, 192.f,  1.f, 0.5f - padPixels,
+		256.f, 0.f,    1.f, 0.f,
+
+		0.f,   0.f,    0.f, 0.5f + padPixels,
+		0.f,   192.f,  0.f, 1.f,
+		256.f, 192.f,  1.f, 1.f,
+		0.f,   0.f,    0.f, 0.5f + padPixels,
+		256.f, 192.f,  1.f, 1.f,
+		256.f, 0.f,    1.f, 0.5f + padPixels
+	};
+
+	glGenBuffers(1, &VertexBuffer);
+	glBindBuffer(GL_ARRAY_BUFFER, VertexBuffer);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+	glGenVertexArrays(1, &VertexArray);
+	glBindVertexArray(VertexArray);
+	glEnableVertexAttribArray(0); // position
+	glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4 * 4, (void*)(0));
+	glEnableVertexAttribArray(1); // texcoord
+	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4 * 4, (void*)(2 * 4));
+
+	// TODO: Could we use this instead of all the screen transforming code in the frontend?
+	// see https://github.com/TASEmulators/BizHawk/issues/3772
+	Frontend::SetupScreenLayout(Width, Height, Frontend::screenLayout_Natural, Frontend::screenRot_0Deg, Frontend::screenSizing_Even, 0, true, false, 1, 1);
+	int discard[2];
+	Frontend::GetScreenTransforms(TransformMatrix, discard);
+
+	glGenTextures(1, &TextureID);
+	glActiveTexture(GL_TEXTURE0);
+	glBindTexture(GL_TEXTURE_2D, TextureID);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, Width, Height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
+	glBindTexture(GL_TEXTURE_2D, 0);
+
+	glGenFramebuffers(1, &FboID);
+	glBindFramebuffer(GL_FRAMEBUFFER, FboID);
+	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, TextureID, 0);
+	glDrawBuffer(GL_COLOR_ATTACHMENT0);
+
+	glGenBuffers(1, &PboID);
+}
+
+std::pair<u32, u32> Present(bool filter)
+{
+	glBindFramebuffer(GL_FRAMEBUFFER, FboID);
+	glDisable(GL_DEPTH_TEST);
+	glDepthMask(false);
+	glDisable(GL_BLEND);
+	glDisable(GL_SCISSOR_TEST);
+	glDisable(GL_STENCIL_TEST);
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	glViewport(0, 0, Width, Height);
+
+	glUseProgram(ShaderProgram[2]);
+	glUniform2f(ShaderSizeULoc, Width, Height);
+
+	glActiveTexture(GL_TEXTURE0);
+	GPU::CurGLCompositor->BindOutputTexture(GPU::FrontBuffer);
+
+	GLint texFilter = filter ? GL_LINEAR : GL_NEAREST;
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, texFilter);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, texFilter);
+
+	glBindBuffer(GL_ARRAY_BUFFER, VertexBuffer);
+	glBindVertexArray(VertexArray);
+
+	glUniformMatrix2x3fv(ShaderTransformULoc, 1, GL_TRUE, &TransformMatrix[0]);
+	glDrawArrays(GL_TRIANGLES, 0, 6);
+
+	glUniformMatrix2x3fv(ShaderTransformULoc, 1, GL_TRUE, &TransformMatrix[6]);
+	glDrawArrays(GL_TRIANGLES, 6, 6);
+
+	glFlush();
+
+	glBindBuffer(GL_PIXEL_PACK_BUFFER, PboID);
+	glBufferData(GL_PIXEL_PACK_BUFFER, Width * Height * sizeof(u32), nullptr, GL_STREAM_READ);
+	glReadPixels(0, 0, Width, Height, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, static_cast<void*>(0));
+
+	return std::make_pair(Width, Height);
+}
+
+ECL_EXPORT u32 GetGLTexture()
+{
+	return TextureID;
+}
+
+ECL_EXPORT void ReadFrameBuffer(u32* buffer)
+{
+	glBindBuffer(GL_PIXEL_PACK_BUFFER, PboID);
+	const auto p = static_cast<const u32*>(glMapBuffer(GL_PIXEL_PACK_BUFFER, GL_READ_ONLY));
+	if (p) {
+		// FBOs render upside down, so flip vertically to counteract that
+		buffer += Width * (Height - 1);
+		const int w = Width;
+		const int h = Height;
+		for (int i = 0; i < h; i++) {
+			std::memcpy(&buffer[-i * w], &p[i * w], Width * sizeof(u32));
+		}
+
+		glUnmapBuffer(GL_PIXEL_PACK_BUFFER);
+	}
+}
+
+}

waterbox/melon/BizGLPresenter.h

@@ -0,0 +1,14 @@
+#ifndef BIZGLPRESENTER_H
+#define BIZGLPRESENTER_H
+
+#include "types.h"
+
+namespace GLPresenter
+{
+
+void Init(u32 scale);
+std::pair<u32, u32> Present(bool filter);
+
+}
+
+#endif

waterbox/melon/BizInterface.cpp

@@ -8,7 +8,10 @@
 #include "BizPlatform/BizConfig.h"
 #include "BizPlatform/BizFile.h"
 #include "BizPlatform/BizLog.h"
+#include "BizPlatform/BizOGL.h"
+
 #include "BizFileManager.h"
+#include "BizGLPresenter.h"
 
 #include <emulibc.h>
 #include <waterboxcore.h>
@@ -23,6 +26,7 @@ struct InitConfig
 	bool DSi;
 	bool ClearNAND;
 	bool LoadDSiWare;
+	bool IsWinApi;
 	int ThreeDeeRenderer;
 	GPU::RenderSettings RenderSettings;
 };
@@ -30,7 +34,8 @@ struct InitConfig
 ECL_EXPORT const char* Init(InitConfig* initConfig,
 	Platform::ConfigCallbackInterface* configCallbackInterface,
 	Platform::FileCallbackInterface* fileCallbackInterface,
-	Platform::LogCallback_t logCallback)
+	Platform::LogCallback_t logCallback,
+	BizOGL::LoadGLProc loadGLProc)
 {
 	Platform::SetConfigCallbacks(*configCallbackInterface);
 	Platform::SetFileCallbacks(*fileCallbackInterface);
@@ -55,6 +60,27 @@ ECL_EXPORT const char* Init(InitConfig* initConfig,
 		return "Failed to init core!";
 	}
 
+	switch (initConfig->ThreeDeeRenderer)
+	{
+		case 0:
+			break;
+		case 1:
+			BizOGL::LoadGL(loadGLProc, BizOGL::LoadGLVersion::V3_2, initConfig->IsWinApi);
+			break;
+#if false
+		case 2:
+			BizOGL::LoadGL(loadGLProc, BizOGL::LoadGLVersion::V4_3, initConfig->IsWinApi);
+			break;
+#endif
+		default:
+			return "Unknown 3DRenderer!";
+	}
+
+	if (initConfig->ThreeDeeRenderer)
+	{
+		GLPresenter::Init(initConfig->RenderSettings.GL_ScaleFactor);
+	}
+
 	GPU::InitRenderer(initConfig->ThreeDeeRenderer);
 	GPU::SetRenderSettings(initConfig->ThreeDeeRenderer, initConfig->RenderSettings);
 
@@ -166,17 +192,22 @@ ECL_EXPORT void FrameAdvance(MyFrameInfo* f)
 
 	NDS::RunFrame();
 
-	if (auto softRenderer = dynamic_cast<GPU3D::SoftRenderer*>(GPU3D::CurrentRenderer.get()))
+	if (GPU3D::CurrentRenderer->Accelerated)
 	{
-		softRenderer->StopRenderThread();
+		std::tie(f->Width, f->Height) = GLPresenter::Present(false);
 	}
+	else
+	{
+		auto softRenderer = reinterpret_cast<GPU3D::SoftRenderer*>(GPU3D::CurrentRenderer.get());
+		softRenderer->StopRenderThread();
 
-	const u32 SingleScreenSize = 256 * 192;
-	memcpy(f->VideoBuffer, GPU::Framebuffer[GPU::FrontBuffer][0], SingleScreenSize * sizeof (u32));
-	memcpy(f->VideoBuffer + SingleScreenSize, GPU::Framebuffer[GPU::FrontBuffer][1], SingleScreenSize * sizeof (u32));
+		constexpr u32 SingleScreenSize = 256 * 192;
+		memcpy(f->VideoBuffer, GPU::Framebuffer[GPU::FrontBuffer][0], SingleScreenSize * sizeof(u32));
+		memcpy(f->VideoBuffer + SingleScreenSize, GPU::Framebuffer[GPU::FrontBuffer][1], SingleScreenSize * sizeof(u32));
 
-	f->Width = 256;
-	f->Height = 384;
+		f->Width = 256;
+		f->Height = 384;
+	}
 
 	f->Samples = SPU::ReadOutput(f->SoundBuffer);
 	if (f->Samples == 0) // hack

waterbox/melon/Makefile

@@ -1,7 +1,7 @@
 CCFLAGS := -Wno-incompatible-pointer-types-discards-qualifiers -Wno-pointer-sign
 
-CXXFLAGS := -DMELONDS_VERSION="" \
-	-I./melonDS/src -I./melonDS/src/teakra/include \
+CXXFLAGS := -DMELONDS_VERSION="" -DOGLRENDERER_ENABLED \
+	-I. -I./melonDS/src -I./melonDS/src/teakra/include \
 	-Wall -Wextra -Werror=int-to-pointer-cast \
 	-Wfatal-errors -Wno-unused-parameter -Wno-unused-variable \
 	-Wno-unused-but-set-variable -Wno-unused-function \
@@ -49,6 +49,12 @@ CORE_SRCS = \
 	Wifi.cpp \
 	WifiAP.cpp
 
+CORE_GL_SRCS = \
+	GPU_OpenGL.cpp \
+	GPU3D_OpenGL.cpp \
+	OpenGLSupport.cpp \
+	frontend/Util_Video.cpp
+
 TEAKRA_SRCS = \
 	ahbm.cpp \
 	apbp.cpp \
@@ -76,18 +82,21 @@ BIZPLATFORM_SRCS = \
 	BizPlatform/BizConfig.cpp \
 	BizPlatform/BizFile.cpp \
 	BizPlatform/BizLog.cpp \
+	BizPlatform/BizOGL.cpp \
 	BizPlatform/BizPlatformStubs.cpp \
 	BizPlatform/BizSaveManager.cpp \
 	BizPlatform/BizThread.cpp \
 
 SRCS = \
 	$(addprefix melonDS/src/,$(CORE_SRCS)) \
+	$(addprefix melonDS/src/,$(CORE_GL_SRCS)) \
 	$(addprefix melonDS/src/teakra/src/,$(TEAKRA_SRCS)) \
 	$(addprefix melonDS/src/fatfs/,$(FATFS_SRCS)) \
 	$(addprefix melonDS/src/,$(MISC_SRCS)) \
 	$(BIZPLATFORM_SRCS) \
 	BizDebugging.cpp \
 	BizFileManager.cpp \
+	BizGLPresenter.cpp \
 	BizInterface.cpp \
 	dthumb.c
 

waterbox/melon/melonDS

@@ -1 +1 @@
-Subproject commit 270f7083caaf477b7ca3456eed9721c3ef239f41
+Subproject commit b200c5476bce4a0c127c304105b3cb7d54f0cee4