[GPU] Surface cache vol 1

CMakeLists.txt

@@ -13,6 +13,7 @@ set (CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
 include_directories(${PROJECT_SOURCE_DIR}/include/)
 include_directories(${PROJECT_SOURCE_DIR}/include/kernel)
 include_directories (${FMT_INCLUDE_DIR})
+include_directories(third_party/boost/)
 include_directories(third_party/elfio/)
 include_directories(third_party/gl3w/)
 include_directories(third_party/imgui/)
@@ -79,6 +80,7 @@ set(HEADER_FILES include/emulator.hpp include/helpers.hpp include/opengl.hpp inc
                  include/services/dsp.hpp include/services/cfg.hpp include/services/region_codes.hpp
                  include/fs/archive_save_data.hpp include/fs/archive_sdmc.hpp include/services/ptm.hpp
                  include/services/mic.hpp include/services/cecd.hpp include/renderer_gl/renderer_gl.hpp
+                 include/renderer_gl/surfaces.hpp include/renderer_gl/surface_cache.hpp
 )
 
 set(THIRD_PARTY_SOURCE_FILES third_party/imgui/imgui.cpp

include/PICA/regs.hpp

@@ -14,6 +14,10 @@ namespace PICAInternalRegs {
 		// Framebuffer registers
 		AlphaTestConfig = 0x104,
 		DepthAndColorMask = 0x107,
+		ColourBufferFormat = 0x117,
+		DepthBufferLoc = 0x11C,
+		ColourBufferLoc = 0x11D,
+		FramebufferSize = 0x11E,
 
 		// Geometry pipeline registers
 		VertexAttribLoc = 0x200,

include/renderer_gl/renderer_gl.hpp

@@ -3,6 +3,7 @@
 #include "helpers.hpp"
 #include "logger.hpp"
 #include "opengl.hpp"
+#include "surface_cache.hpp"
 
 struct Vertex {
 	OpenGL::vec4 position;
@@ -21,6 +22,17 @@ class Renderer {
 	GLint alphaControlLoc = -1;
 	u32 oldAlphaControl = 0;
 
+	SurfaceCache<DepthBuffer, 10> depthBufferCache;
+	SurfaceCache<ColourBuffer, 10> colourBufferCache;
+	OpenGL::uvec2 fbSize; // The size of the framebuffer (ie both the colour and depth buffer)'
+
+	u32 colourBufferLoc; // Location in 3DS VRAM for the colour buffer
+	ColourBuffer::Formats colourBufferFormat; // Format of the colours stored in the colour buffer
+	
+	// Same for the depth/stencil buffer
+	u32 depthBufferLoc;
+	DepthBuffer::Formats depthBufferFormat;
+
 	// Dummy VAO/VBO for blitting the final output
 	OpenGL::VertexArray dummyVAO;
 	OpenGL::VertexBuffer dummyVBO;
@@ -28,6 +40,8 @@ class Renderer {
 	static constexpr u32 regNum = 0x300; // Number of internal PICA registers
 	const std::array<u32, regNum>& regs;
 
+	OpenGL::Framebuffer getColourFBO();
+
 	MAKE_LOG_FUNCTION(log, rendererLogger)
 
 public:
@@ -40,5 +54,19 @@ public:
 	void clearBuffer(u32 startAddress, u32 endAddress, u32 value, u32 control); // Clear a GPU buffer in VRAM
 	void drawVertices(OpenGL::Primitives primType, Vertex* vertices, u32 count); // Draw the given vertices
 
+	void setFBSize(u32 width, u32 height) {
+		fbSize.x() = width;
+		fbSize.y() = height;
+	}
+
+	void setColourFormat(ColourBuffer::Formats format) { colourBufferFormat = format; }
+	void setColourFormat(u32 format) { colourBufferFormat = static_cast<ColourBuffer::Formats>(format); }
+
+	void setDepthFormat(DepthBuffer::Formats format) { depthBufferFormat = format; }
+	void setDepthFormat(u32 format) { depthBufferFormat = static_cast<DepthBuffer::Formats>(format); }
+
+	void setColourBufferLoc(u32 loc) { colourBufferLoc = loc; }
+	void setDepthBufferLoc(u32 loc) { depthBufferLoc = loc; }
+
 	static constexpr u32 vertexBufferSize = 0x1500;
 };

include/renderer_gl/surface_cache.hpp

@@ -0,0 +1,62 @@
+#pragma once
+#include <functional>
+#include <optional>
+#include "surfaces.hpp"
+
+// Surface cache class that can fit "capacity" instances of the "SurfaceType" class of surfaces
+// SurfaceType *must* have all of the following
+// - An "allocate" function that allocates GL resources for the surfaces
+// - A "free" function that frees up all resources the surface is taking up
+// - A "matches" function that, when provided with a SurfaceType object reference
+// Will tell us if the 2 surfaces match (Only as far as location in VRAM, format, dimensions, etc)
+// Are concerned. We could overload the == operator, but that implies full equality
+// Including equality of the allocated OpenGL resources, which we don't want
+// - A "valid" member that tells us whether the function is still valid or not
+template <typename SurfaceType, size_t capacity>
+class SurfaceCache {
+    // Vanilla std::optional can't hold actual references
+    using OptionalRef = std::optional<std::reference_wrapper<SurfaceType>>;
+    static_assert(std::is_same<SurfaceType, ColourBuffer>() || std::is_same<SurfaceType, DepthBuffer>(),
+        "Invalid surface type");
+
+    size_t size;
+    std::array<SurfaceType, capacity> buffer;
+
+public:
+    void reset() {
+        size = 0;
+        for (auto& e : buffer) { // Free the VRAM of all surfaces
+            e.free();
+        }
+    }
+
+    OptionalRef find(SurfaceType& other) {
+        for (auto& e : buffer) {
+            if (e.matches(other) && e.valid)
+                return e;
+        }
+
+        return std::nullopt;
+    }
+
+    // Adds a surface object to the cache and returns it
+    SurfaceType add(SurfaceType& surface) {
+        if (size >= capacity) {
+            Helpers::panic("Surface cache full! Add emptying!");
+        }
+        size++;
+
+        // Find an invalid entry in the cache and overwrite it with the new surface
+        for (auto& e : buffer) {
+            if (!e.valid) {
+                e = surface;
+                e.allocate();
+                Sleep(2000);
+                return e;
+            }
+        }
+
+        // This should be unreachable but helps to panic anyways
+        Helpers::panic("Couldn't add surface to cache\n");
+    }
+};

include/renderer_gl/surfaces.hpp

@@ -0,0 +1,125 @@
+#pragma once
+#include "boost/icl/interval.hpp"
+#include "helpers.hpp"
+#include "opengl.hpp"
+
+template <typename T>
+using Interval = boost::icl::right_open_interval<T>;
+
+struct ColourBuffer {
+    enum class Formats : u32 {
+        RGBA8 = 0,
+        BGR8 = 1,
+        RGB5A1 = 2,
+        RGB565 = 3,
+        RGBA4 = 4,
+        
+        Trash1 = 5, Trash2 = 6, Trash3 = 7 // Technically selectable, but their function is unknown
+    };
+
+    u32 location;
+    Formats format;
+    OpenGL::uvec2 size;
+    bool valid;
+
+    // Range of VRAM taken up by buffer
+    Interval<u32> range;
+    // OpenGL resources allocated to buffer
+    OpenGL::Texture texture;
+    OpenGL::Framebuffer fbo;
+
+    ColourBuffer() : valid(false) {}
+
+    ColourBuffer(u32 loc, Formats format, u32 x, u32 y, bool valid = true)
+        : location(loc), format(format), size({x, y}), valid(valid) {
+
+        u64 endLoc = (u64)loc + sizeInBytes();
+        // Check if start and end are valid here
+        range = Interval<u32>(loc, (u32)endLoc);
+    }
+
+    void allocate() {
+        printf("Make this colour buffer allocate itself\n");
+    }
+
+    void free() {
+        valid = false;
+        printf("Make this colour buffer free itself\n");
+    }
+
+    bool matches(ColourBuffer& other) {
+        return location == other.location && format == other.format &&
+            size.x() == other.size.x() && size.y() == other.size.y();
+    }
+
+    // Size occupied by each pixel in bytes
+    // All formats are 16BPP except for RGBA8 (32BPP) and BGR8 (24BPP)
+    size_t sizePerPixel() {
+        switch (format) {
+            case Formats::BGR8: return 3;
+            case Formats::RGBA8: return 4;
+            default: return 2;
+        }
+    }
+
+    size_t sizeInBytes() {
+        return (size_t)size.x() * (size_t)size.y() * sizePerPixel();
+    }
+};
+
+struct DepthBuffer {
+    enum class Formats : u32 {
+        Depth16 = 0,
+        Garbage = 1,
+        Depth24 = 2,
+        Depth24Stencil8 = 3
+    };
+
+    u32 location;
+    Formats format;
+    OpenGL::uvec2 size; // Implicitly set to the size of the framebuffer
+    bool valid;
+
+    // Range of VRAM taken up by buffer
+    Interval<u32> range;
+    // OpenGL texture used for storing depth/stencil
+    OpenGL::Texture texture;
+
+    DepthBuffer() : valid(false) {}
+
+    DepthBuffer(u32 loc, Formats format, u32 x, u32 y, bool valid = true) :
+        location(loc), format(format), size({x, y}), valid(valid) {}
+
+    bool hasStencil() {
+        return format == Formats::Depth24Stencil8;
+    }
+
+    void allocate() {
+        printf("Make this depth buffer allocate itself\n");
+    }
+
+    void free() {
+        valid = false;
+        printf("Make this depth buffer free itself\n");
+    }
+
+    bool matches(DepthBuffer& other) {
+        return location == other.location && format == other.format &&
+            size.x() == other.size.x() && size.y() == other.size.y();
+    }
+
+    // Size occupied by each pixel in bytes
+    size_t sizePerPixel() {
+        switch (format) {
+            case Formats::Depth16: return 2;
+            case Formats::Depth24: return 3;
+            case Formats::Depth24Stencil8: return 4;
+
+            default: return 1; // Invalid format
+        }
+    }
+
+    size_t sizeInBytes() {
+        return (size_t)size.x() * (size_t)size.y() * sizePerPixel();
+    }
+};

src/core/PICA/regs.cpp

@@ -59,6 +59,31 @@ void GPU::writeInternalReg(u32 index, u32 value, u32 mask) {
 			fixedAttribMask = (value >> 16) & 0xfff; // Determines which vertex attributes are fixed for all vertices
 			break;
 
+		case ColourBufferLoc: {
+			u32 loc = (value & 0x0fffffff) << 3;
+			renderer.setColourBufferLoc(loc);
+			break;
+		};
+
+		case ColourBufferFormat: {
+			u32 format = (value >> 16) & 7;
+			renderer.setColourFormat(format);
+			break;
+		}
+
+		case DepthBufferLoc: {
+			u32 loc = (value & 0x0fffffff) << 3;
+			renderer.setDepthBufferLoc(loc);
+			break;
+		}
+
+		case FramebufferSize: {
+			const u32 width = value & 0x7ff;
+			const u32 height = ((value >> 12) & 0x3ff) + 1;
+			renderer.setFBSize(width, height);
+			break;
+		}
+
 		case VertexFloatUniformIndex:
 			shaderUnit.vs.setFloatUniformIndex(value);
 			break;

src/core/renderer_gl/renderer_gl.cpp

@@ -105,6 +105,18 @@ const char* displayFragmentShader = R"(
     }
 )";
 
+void Renderer::reset() {
+	depthBufferCache.reset();
+	colourBufferCache.reset();
+
+	// Init the colour/depth buffer settings to some random defaults on reset
+	colourBufferLoc = 0;
+	colourBufferFormat = ColourBuffer::Formats::RGBA8;
+
+	depthBufferLoc = 0;
+	depthBufferFormat = DepthBuffer::Formats::Depth16;
+}
+
 void Renderer::initGraphicsContext() {
 	// Set up texture for top screen
 	fboTexture.create(400, 240, GL_RGBA8);
@@ -156,6 +168,7 @@ void Renderer::initGraphicsContext() {
 
 	dummyVBO.create();
 	dummyVAO.create();
+	reset();
 }
 
 void Renderer::getGraphicsContext() {
@@ -168,6 +181,8 @@ void Renderer::getGraphicsContext() {
 	triangleProgram.use();
 }
 
+OpenGL::Framebuffer poop;
+
 void Renderer::drawVertices(OpenGL::Primitives primType, Vertex* vertices, u32 count) {
 	// Adjust alpha test if necessary
 	const u32 alphaControl = regs[PICAInternalRegs::AlphaTestConfig];
@@ -176,6 +191,8 @@ void Renderer::drawVertices(OpenGL::Primitives primType, Vertex* vertices, u32 c
 		glUniform1ui(alphaControlLoc, alphaControl);
 	}
 
+	poop = getColourFBO();
+
 	const u32 depthControl = regs[PICAInternalRegs::DepthAndColorMask];
 	bool depthEnable = depthControl & 1;
 	bool depthWriteEnable = (depthControl >> 12) & 1;
@@ -253,3 +270,16 @@ void Renderer::clearBuffer(u32 startAddress, u32 endAddress, u32 value, u32 cont
 	OpenGL::setClearColor(r, g, b, a);
 	OpenGL::clearColor();
 }
+
+OpenGL::Framebuffer Renderer::getColourFBO() {
+	//We construct a colour buffer object and see if our cache has any matching colour buffers in it
+	// If not, we allocate a texture & FBO for our framebuffer and store it in the cache 
+	ColourBuffer sampleBuffer(colourBufferLoc, colourBufferFormat, fbSize.x(), fbSize.y());
+	auto buffer = colourBufferCache.find(sampleBuffer);
+
+	if (buffer.has_value()) {
+		return buffer.value().get().fbo;
+	} else {
+		return colourBufferCache.add(sampleBuffer).fbo;
+	}
+}