gl_rasterizer: Use the shared texture buffer for the fog lut.

src/video_core/renderer_opengl/gl_rasterizer.cpp

@@ -135,16 +135,6 @@ RasterizerOpenGL::RasterizerOpenGL()
     glActiveTexture(TextureUnits::TextureBufferLUT_RGBA.Enum());
     glTexBuffer(GL_TEXTURE_BUFFER, GL_RGBA32F, texture_buffer.GetHandle());
 
-    // Setup the LUT for the fog
-    fog_lut.Create();
-    state.fog_lut.texture_buffer = fog_lut.handle;
-    state.Apply();
-    fog_lut_buffer.Create();
-    glBindBuffer(GL_TEXTURE_BUFFER, fog_lut_buffer.handle);
-    glBufferData(GL_TEXTURE_BUFFER, sizeof(GLfloat) * 2 * 128, nullptr, GL_DYNAMIC_DRAW);
-    glActiveTexture(TextureUnits::FogLUT.Enum());
-    glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, fog_lut_buffer.handle);
-
     // Setup the noise LUT for proctex
     proctex_noise_lut.Create();
     state.proctex_noise_lut.texture_buffer = proctex_noise_lut.handle;
@@ -1978,7 +1968,7 @@ void RasterizerOpenGL::SyncAndUploadLUTs() {
     uniform_block_data.lighting_lut_dirty_any = false;
 
     // Sync the fog lut
-    if (uniform_block_data.fog_lut_dirty) {
+    if (uniform_block_data.fog_lut_dirty || invalidate) {
         std::array<GLvec2, 128> new_data;
 
         std::transform(Pica::g_state.fog.lut.begin(), Pica::g_state.fog.lut.end(), new_data.begin(),
@@ -1986,11 +1976,12 @@ void RasterizerOpenGL::SyncAndUploadLUTs() {
                            return GLvec2{entry.ToFloat(), entry.DiffToFloat()};
                        });
 
-        if (new_data != fog_lut_data) {
+        if (new_data != fog_lut_data || invalidate) {
             fog_lut_data = new_data;
-            glBindBuffer(GL_TEXTURE_BUFFER, fog_lut_buffer.handle);
+            std::memcpy(buffer + bytes_used, new_data.data(), new_data.size() * sizeof(GLvec2));
-            glBufferSubData(GL_TEXTURE_BUFFER, 0, new_data.size() * sizeof(GLvec2),
+            uniform_block_data.data.fog_lut_offset = (offset + bytes_used) / sizeof(GLvec2);
-                            new_data.data());
+            uniform_block_data.dirty = true;
+            bytes_used += new_data.size() * sizeof(GLvec2);
         }
         uniform_block_data.fog_lut_dirty = false;
     }

src/video_core/renderer_opengl/gl_rasterizer.h

@@ -290,9 +290,6 @@ private:
     OGLTexture texture_buffer_lut_rgba;
 
     std::array<std::array<GLvec2, 256>, Pica::LightingRegs::NumLightingSampler> lighting_lut_data{};
-
-    OGLBuffer fog_lut_buffer;
-    OGLTexture fog_lut;
     std::array<GLvec2, 128> fog_lut_data{};
 
     OGLBuffer proctex_noise_lut_buffer;

src/video_core/renderer_opengl/gl_shader_gen.cpp

@@ -1224,7 +1224,6 @@ uniform sampler2D tex2;
 uniform samplerCube tex_cube;
 uniform samplerBuffer texture_buffer_lut_rg;
 uniform samplerBuffer texture_buffer_lut_rgba;
-uniform samplerBuffer fog_lut;
 uniform samplerBuffer proctex_noise_lut;
 uniform samplerBuffer proctex_color_map;
 uniform samplerBuffer proctex_alpha_map;
@@ -1494,7 +1493,8 @@ vec4 secondary_fragment_color = vec4(0.0);
         // Generate clamped fog factor from LUT for given fog index
         out += "float fog_i = clamp(floor(fog_index), 0.0, 127.0);\n";
         out += "float fog_f = fog_index - fog_i;\n";
-        out += "vec2 fog_lut_entry = texelFetch(fog_lut, int(fog_i) + fog_lut_offset).rg;\n";
+        out += "vec2 fog_lut_entry = texelFetch(texture_buffer_lut_rg, int(fog_i) + "
+               "fog_lut_offset).rg;\n";
         out += "float fog_factor = fog_lut_entry.r + fog_lut_entry.g * fog_f;\n";
         out += "fog_factor = clamp(fog_factor, 0.0, 1.0);\n";
 

src/video_core/renderer_opengl/gl_shader_manager.cpp

@@ -57,7 +57,6 @@ static void SetShaderSamplerBindings(GLuint shader) {
     // Set the texture samplers to correspond to different lookup table texture units
     SetShaderSamplerBinding(shader, "texture_buffer_lut_rg", TextureUnits::TextureBufferLUT_RG);
     SetShaderSamplerBinding(shader, "texture_buffer_lut_rgba", TextureUnits::TextureBufferLUT_RGBA);
-    SetShaderSamplerBinding(shader, "fog_lut", TextureUnits::FogLUT);
     SetShaderSamplerBinding(shader, "proctex_noise_lut", TextureUnits::ProcTexNoiseLUT);
     SetShaderSamplerBinding(shader, "proctex_color_map", TextureUnits::ProcTexColorMap);
     SetShaderSamplerBinding(shader, "proctex_alpha_map", TextureUnits::ProcTexAlphaMap);

src/video_core/renderer_opengl/gl_state.cpp

@@ -58,8 +58,6 @@ OpenGLState::OpenGLState() {
     texture_buffer_lut_rg.texture_buffer = 0;
     texture_buffer_lut_rgba.texture_buffer = 0;
 
-    fog_lut.texture_buffer = 0;
-
     proctex_lut.texture_buffer = 0;
     proctex_diff_lut.texture_buffer = 0;
     proctex_color_map.texture_buffer = 0;
@@ -235,12 +233,6 @@ void OpenGLState::Apply() const {
         glBindTexture(GL_TEXTURE_BUFFER, texture_buffer_lut_rgba.texture_buffer);
     }
 
-    // Fog LUT
-    if (fog_lut.texture_buffer != cur_state.fog_lut.texture_buffer) {
-        glActiveTexture(TextureUnits::FogLUT.Enum());
-        glBindTexture(GL_TEXTURE_BUFFER, fog_lut.texture_buffer);
-    }
-
     // ProcTex Noise LUT
     if (proctex_noise_lut.texture_buffer != cur_state.proctex_noise_lut.texture_buffer) {
         glActiveTexture(TextureUnits::ProcTexNoiseLUT.Enum());
@@ -386,8 +378,6 @@ OpenGLState& OpenGLState::ResetTexture(GLuint handle) {
         texture_buffer_lut_rg.texture_buffer = 0;
     if (texture_buffer_lut_rgba.texture_buffer == handle)
         texture_buffer_lut_rgba.texture_buffer = 0;
-    if (fog_lut.texture_buffer == handle)
-        fog_lut.texture_buffer = 0;
     if (proctex_noise_lut.texture_buffer == handle)
         proctex_noise_lut.texture_buffer = 0;
     if (proctex_color_map.texture_buffer == handle)

src/video_core/renderer_opengl/gl_state.h

@@ -20,7 +20,6 @@ constexpr TextureUnit PicaTexture(int unit) {
     return TextureUnit{unit};
 }
 
-constexpr TextureUnit FogLUT{4};
 constexpr TextureUnit ProcTexNoiseLUT{5};
 constexpr TextureUnit ProcTexColorMap{6};
 constexpr TextureUnit ProcTexAlphaMap{7};
@@ -112,10 +111,6 @@ public:
         GLuint texture_buffer; // GL_TEXTURE_BINDING_BUFFER
     } texture_buffer_lut_rgba;
 
-    struct {
-        GLuint texture_buffer; // GL_TEXTURE_BINDING_BUFFER
-    } fog_lut;
-
     struct {
         GLuint texture_buffer; // GL_TEXTURE_BINDING_BUFFER
     } proctex_noise_lut;