renderer_base: Make creation of the rasterizer, the responsibility of the renderers themselves

Given we use a base-class type within the renderer for the rasterizer
(RasterizerInterface), we want to allow renderers to perform more
complex initialization if they need to do such a thing. This makes it
important to reserve type information.

Given the OpenGL renderer is quite simple settings-wise, this is just a
simple shuffling of the initialization code. For something like Vulkan
however this might involve doing something like:

// Initialize and call rasterizer-specific function that requires
// the full type of the instance created.
auto raster = std::make_unique<VulkanRasterizer>(some, params);
raster->CallSomeVulkanRasterizerSpecificFunction();

// Assign to base class variable
rasterizer = std::move(raster)

src/video_core/renderer_opengl/renderer_opengl.cpp

@@ -16,6 +16,7 @@
 #include "core/memory.h"
 #include "core/settings.h"
 #include "core/tracer/recorder.h"
+#include "video_core/renderer_opengl/gl_rasterizer.h"
 #include "video_core/renderer_opengl/renderer_opengl.h"
 #include "video_core/utils.h"
 
@@ -142,7 +143,6 @@ void RendererOpenGL::SwapBuffers(boost::optional<const Tegra::FramebufferConfig&
 
     // Restore the rasterizer state
     prev_state.Apply();
-    RefreshRasterizerSetting();
 }
 
 /**
@@ -276,6 +276,14 @@ void RendererOpenGL::InitOpenGLObjects() {
     LoadColorToActiveGLTexture(0, 0, 0, 0, screen_info.texture);
 }
 
+void RendererOpenGL::CreateRasterizer() {
+    if (rasterizer) {
+        return;
+    }
+
+    rasterizer = std::make_unique<RasterizerOpenGL>(render_window);
+}
+
 void RendererOpenGL::ConfigureFramebufferTexture(TextureInfo& texture,
                                                  const Tegra::FramebufferConfig& framebuffer) {
 
@@ -463,8 +471,7 @@ bool RendererOpenGL::Init() {
     }
 
     InitOpenGLObjects();
-
-    RefreshRasterizerSetting();
+    CreateRasterizer();
 
     return true;
 }

src/video_core/renderer_opengl/renderer_opengl.h

@@ -59,6 +59,8 @@ public:
 
 private:
     void InitOpenGLObjects();
+    void CreateRasterizer();
+
     void ConfigureFramebufferTexture(TextureInfo& texture,
                                      const Tegra::FramebufferConfig& framebuffer);
     void DrawScreen();