Replace the previous OpenGL loader with a glad-generated 3.3 one

The main advantage of switching to glad from glLoadGen is that, apart
from being actively maintained, it supports a customizable entrypoint
loader function, which makes it possible to also support OpenGL ES.

src/citra/CMakeLists.txt

@@ -15,7 +15,7 @@ create_directory_groups(${SRCS} ${HEADERS})
 
 add_executable(citra ${SRCS} ${HEADERS})
 target_link_libraries(citra core video_core common)
-target_link_libraries(citra ${GLFW_LIBRARIES} ${OPENGL_gl_LIBRARY} inih)
+target_link_libraries(citra ${GLFW_LIBRARIES} ${OPENGL_gl_LIBRARY} inih glad)
 if (MSVC)
     target_link_libraries(citra getopt)
 endif()
@@ -23,4 +23,4 @@ target_link_libraries(citra ${PLATFORM_LIBRARIES})
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Linux|FreeBSD|OpenBSD|NetBSD")
     install(TARGETS citra RUNTIME DESTINATION "${CMAKE_INSTALL_PREFIX}/bin")
-endif()
+endif()

src/citra/emu_window/emu_window_glfw.cpp

@@ -7,7 +7,7 @@
 #include <string>
 
 // Let’s use our own GL header, instead of one from GLFW.
-#include "video_core/renderer_opengl/generated/gl_3_2_core.h"
+#include <glad/glad.h>
 #define GLFW_INCLUDE_NONE
 #include <GLFW/glfw3.h>
 

src/video_core/CMakeLists.txt

@@ -1,5 +1,4 @@
 set(SRCS
-            renderer_opengl/generated/gl_3_2_core.c
             renderer_opengl/gl_rasterizer.cpp
             renderer_opengl/gl_rasterizer_cache.cpp
             renderer_opengl/gl_shader_util.cpp
@@ -19,7 +18,6 @@ set(SRCS
 
 set(HEADERS
             debug_utils/debug_utils.h
-            renderer_opengl/generated/gl_3_2_core.h
             renderer_opengl/gl_rasterizer.h
             renderer_opengl/gl_rasterizer_cache.h
             renderer_opengl/gl_resource_manager.h
@@ -53,6 +51,7 @@ endif()
 create_directory_groups(${SRCS} ${HEADERS})
 
 add_library(video_core STATIC ${SRCS} ${HEADERS})
+target_link_libraries(video_core glad)
 
 if (PNG_FOUND)
     target_link_libraries(video_core ${PNG_LIBRARIES})

src/video_core/renderer_opengl/generated/Readme.md

@@ -1,5 +0,0 @@
-These file were generated by the [glLoadGen](https://bitbucket.org/alfonse/glloadgen/wiki/Home) OpenGL loader generator and have been checked in as-is. You can re-generate them using version 2.0.2 of glLoadGen and executing the following command:
-
-```
-lua LoadGen.lua -version 3.2 -profile core -indent space 3_2_core
-```

src/video_core/renderer_opengl/gl_rasterizer.cpp

@@ -5,6 +5,8 @@
 #include <cstring>
 #include <memory>
 
+#include <glad/glad.h>
+
 #include "common/color.h"
 #include "common/math_util.h"
 #include "common/microprofile.h"
@@ -21,8 +23,6 @@
 #include "video_core/renderer_opengl/gl_shader_util.h"
 #include "video_core/renderer_opengl/pica_to_gl.h"
 
-#include "generated/gl_3_2_core.h"
-
 static bool IsPassThroughTevStage(const Pica::Regs::TevStageConfig& stage) {
     return (stage.color_op == Pica::Regs::TevStageConfig::Operation::Replace &&
             stage.alpha_op == Pica::Regs::TevStageConfig::Operation::Replace &&

src/video_core/renderer_opengl/gl_resource_manager.h

@@ -6,9 +6,10 @@
 
 #include <utility>
 
+#include <glad/glad.h>
+
 #include "common/common_types.h"
 
-#include "video_core/renderer_opengl/generated/gl_3_2_core.h"
 #include "video_core/renderer_opengl/gl_shader_util.h"
 #include "video_core/renderer_opengl/gl_state.h"
 

src/video_core/renderer_opengl/gl_shader_util.h

@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include "generated/gl_3_2_core.h"
+#include <glad/glad.h>
 
 namespace ShaderUtil {
 

src/video_core/renderer_opengl/gl_state.h

@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include "generated/gl_3_2_core.h"
+#include <glad/glad.h>
 
 class OpenGLState {
 public:

src/video_core/renderer_opengl/pica_to_gl.h

@@ -4,12 +4,12 @@
 
 #pragma once
 
+#include <glad/glad.h>
+
 #include "common/common_types.h"
 
 #include "video_core/pica.h"
 
-#include "generated/gl_3_2_core.h"
-
 namespace PicaToGL {
 
 inline GLenum TextureFilterMode(Pica::Regs::TextureConfig::TextureFilter mode) {

src/video_core/renderer_opengl/renderer_opengl.cpp

@@ -373,8 +373,8 @@ void RendererOpenGL::SetWindow(EmuWindow* window) {
 void RendererOpenGL::Init() {
     render_window->MakeCurrent();
 
-    int err = ogl_LoadFunctions();
-    if (ogl_LOAD_SUCCEEDED != err) {
+    // TODO: Make frontends initialize this, so they can use gladLoadGLLoader with their own loaders
+    if (!gladLoadGL()) {
         LOG_CRITICAL(Render_OpenGL, "Failed to initialize GL functions! Exiting...");
         exit(-1);
     }

src/video_core/renderer_opengl/renderer_opengl.h

@@ -6,7 +6,7 @@
 
 #include <array>
 
-#include "generated/gl_3_2_core.h"
+#include <glad/glad.h>
 
 #include "common/math_util.h"