Trongle

src/core/PICA/renderer_opengl.cpp

@@ -0,0 +1,160 @@
+#include "PICA/gpu.hpp"
+#include "opengl.hpp"
+
+// This is all hacked up to display our first triangle
+
+const char* vertexShader = R"(
+	#version 420 core
+	
+	layout (location = 0) in vec4 coords;
+	layout (location = 1) in vec4 vertexColour;
+
+	out vec4 colour;
+
+	void main() {
+		gl_Position = coords;
+		colour = vertexColour;
+	}
+)";
+
+const char* fragmentShader = R"(
+	#version 420 core
+	
+	in vec4 colour;
+	out vec4 fragColour;
+
+	void main() {
+		fragColour = colour;
+	}
+)";
+
+const char* displayVertexShader = R"(
+	#version 420 core
+	out vec2 UV;
+
+	void main() {
+		const vec4 positions[4] = vec4[](
+          vec4(-1.0, 1.0, 1.0, 1.0),    // Top-left
+          vec4(1.0, 1.0, 1.0, 1.0),     // Top-right
+          vec4(-1.0, -1.0, 1.0, 1.0),   // Bottom-left
+          vec4(1.0, -1.0, 1.0, 1.0)     // Bottom-right
+        );
+
+		// The 3DS displays both screens' framebuffer rotated 90 deg counter clockwise
+		// So we adjust our texcoords accordingly
+		const vec2 texcoords[4] = vec2[](
+				vec2(1.0, 1.0), // Top-right
+				vec2(1.0, 0.0), // Bottom-right
+				vec2(0.0, 1.0), // Top-left
+				vec2(0.0, 0.0)  // Bottom-left
+        );
+
+		gl_Position = positions[gl_VertexID];
+        UV = texcoords[gl_VertexID];
+	}
+)";
+
+const char* displayFragmentShader = R"(
+    #version 420 core
+    in vec2 UV;
+    out vec4 FragColor;
+
+    uniform sampler2D u_texture; // TODO: Properly init this to 0 when I'm not lazy
+    void main() {
+		FragColor = texture(u_texture, UV);
+    }
+)";
+
+void GPU::initGraphicsContext() {
+	// Set up texture for top screen
+	fboTexture.create(400, 240, GL_RGBA8);
+	fboTexture.bind();
+
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glBindTexture(GL_TEXTURE_2D, 0);
+
+	fbo.createWithDrawTexture(fboTexture);
+	fbo.bind(OpenGL::DrawFramebuffer);
+
+	OpenGL::setViewport(400, 240);
+	OpenGL::setClearColor(0.0, 0.0, 0.0, 1.0);
+	OpenGL::clearColor();
+
+	OpenGL::Shader vert(vertexShader, OpenGL::Vertex);
+	OpenGL::Shader frag(fragmentShader, OpenGL::Fragment);
+	triangleProgram.create({ vert, frag });
+
+	OpenGL::Shader vertDisplay(displayVertexShader, OpenGL::Vertex);
+	OpenGL::Shader fragDisplay(displayFragmentShader, OpenGL::Fragment);
+	displayProgram.create({ vertDisplay, fragDisplay });
+
+	vbo.createFixedSize(sizeof(Vertex) * vertexBufferSize, GL_STREAM_DRAW);
+	vbo.bind();
+	vao.create();
+	vao.bind();
+
+	// Position (x, y, z, w) attributes
+	vao.setAttributeFloat<float>(0, 4, sizeof(Vertex), offsetof(Vertex, position));
+	vao.enableAttribute(0);
+	// Colour attribute
+	vao.setAttributeFloat<float>(1, 4, sizeof(Vertex), offsetof(Vertex, colour));
+	vao.enableAttribute(1);
+
+	dummyVBO.create();
+	dummyVAO.create();
+}
+
+void GPU::getGraphicsContext() {
+	OpenGL::disableDepth();
+	OpenGL::disableScissor();
+	OpenGL::setViewport(400, 240);
+	fbo.bind(OpenGL::DrawAndReadFramebuffer);
+
+	vbo.bind();
+	vao.bind();
+	triangleProgram.use();
+}
+
+void GPU::drawVertices(OpenGL::Primitives primType, Vertex* vertices, u32 count) {
+	vbo.bufferVertsSub(vertices, count);
+	OpenGL::draw(primType, count);
+}
+
+constexpr u32 topScreenBuffer = 0x1f000000;
+constexpr u32 bottomScreenBuffer = 0x1f300000;
+
+// Quick hack to display top screen for now
+void GPU::display() {
+	OpenGL::disableScissor();
+	OpenGL::bindScreenFramebuffer();
+	fboTexture.bind();
+	displayProgram.use();
+
+	dummyVBO.bind();
+	dummyVAO.bind();
+	OpenGL::setViewport(0, 240, 400, 240);
+
+	OpenGL::draw(OpenGL::TriangleStrip, 4);
+}
+
+void GPU::clearBuffer(u32 startAddress, u32 endAddress, u32 value, u32 control) {
+	log("GPU: Clear buffer\nStart: %08X End: %08X\nValue: %08X Control: %08X\n", startAddress, endAddress, value, control);
+
+	const float r = float((value >> 24) & 0xff) / 255.0;
+	const float g = float((value >> 16) & 0xff) / 255.0;
+	const float b = float((value >> 8) & 0xff) / 255.0;
+	const float a = float(value & 0xff) / 255.0;
+
+	if (startAddress == topScreenBuffer) {
+		log("GPU: Cleared top screen\n");
+	} else if (startAddress == bottomScreenBuffer) {
+		log("GPU: Tried to clear bottom screen\n");
+		return;
+	} else {
+		log("GPU: Clearing some unknown buffer\n");
+	}
+
+	OpenGL::setClearColor(r, g, b, a);
+	OpenGL::clearColor();
+}