From be9e952bdc33b6763618ee66046ce84c0ff18a34 Mon Sep 17 00:00:00 2001
From: wwylele <wwylele@gmail.com>
Date: Fri, 16 Jun 2017 16:16:28 +0300
Subject: [PATCH] gl_rasterizer: manage texture ids in one place

---
 .../renderer_opengl/gl_rasterizer.cpp         | 47 ++++++++++---------
 src/video_core/renderer_opengl/gl_state.cpp   | 16 +++----
 src/video_core/renderer_opengl/gl_state.h     | 23 +++++++++
 3 files changed, 55 insertions(+), 31 deletions(-)

diff --git a/src/video_core/renderer_opengl/gl_rasterizer.cpp b/src/video_core/renderer_opengl/gl_rasterizer.cpp
index c73e1d6e2b..c018afbccf 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.cpp
+++ b/src/video_core/renderer_opengl/gl_rasterizer.cpp
@@ -102,7 +102,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     glBufferData(GL_TEXTURE_BUFFER,
                  sizeof(GLfloat) * 2 * 256 * Pica::LightingRegs::NumLightingSampler, nullptr,
                  GL_DYNAMIC_DRAW);
-    glActiveTexture(GL_TEXTURE15);
+    glActiveTexture(TextureUnits::LightingLUT.Enum());
     glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, lighting_lut_buffer.handle);
 
     // Setup the LUT for the fog
@@ -112,7 +112,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     }
     state.Apply();
 
-    glActiveTexture(GL_TEXTURE9);
+    glActiveTexture(TextureUnits::FogLUT.Enum());
     glTexImage1D(GL_TEXTURE_1D, 0, GL_R32UI, 128, 0, GL_RED_INTEGER, GL_UNSIGNED_INT, nullptr);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -121,7 +121,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     proctex_noise_lut.Create();
     state.proctex_noise_lut.texture_1d = proctex_noise_lut.handle;
     state.Apply();
-    glActiveTexture(GL_TEXTURE10);
+    glActiveTexture(TextureUnits::ProcTexNoiseLUT.Enum());
     glTexImage1D(GL_TEXTURE_1D, 0, GL_RG32F, 128, 0, GL_RG, GL_FLOAT, nullptr);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -130,7 +130,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     proctex_color_map.Create();
     state.proctex_color_map.texture_1d = proctex_color_map.handle;
     state.Apply();
-    glActiveTexture(GL_TEXTURE11);
+    glActiveTexture(TextureUnits::ProcTexColorMap.Enum());
     glTexImage1D(GL_TEXTURE_1D, 0, GL_RG32F, 128, 0, GL_RG, GL_FLOAT, nullptr);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -139,7 +139,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     proctex_alpha_map.Create();
     state.proctex_alpha_map.texture_1d = proctex_alpha_map.handle;
     state.Apply();
-    glActiveTexture(GL_TEXTURE12);
+    glActiveTexture(TextureUnits::ProcTexAlphaMap.Enum());
     glTexImage1D(GL_TEXTURE_1D, 0, GL_RG32F, 128, 0, GL_RG, GL_FLOAT, nullptr);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -148,7 +148,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     proctex_lut.Create();
     state.proctex_lut.texture_1d = proctex_lut.handle;
     state.Apply();
-    glActiveTexture(GL_TEXTURE13);
+    glActiveTexture(TextureUnits::ProcTexLUT.Enum());
     glTexImage1D(GL_TEXTURE_1D, 0, GL_RGBA32F, 256, 0, GL_RGBA, GL_FLOAT, nullptr);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -157,7 +157,7 @@ RasterizerOpenGL::RasterizerOpenGL() : shader_dirty(true) {
     proctex_diff_lut.Create();
     state.proctex_diff_lut.texture_1d = proctex_diff_lut.handle;
     state.Apply();
-    glActiveTexture(GL_TEXTURE14);
+    glActiveTexture(TextureUnits::ProcTexDiffLUT.Enum());
     glTexImage1D(GL_TEXTURE_1D, 0, GL_RGBA32F, 256, 0, GL_RGBA, GL_FLOAT, nullptr);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -1185,55 +1185,55 @@ void RasterizerOpenGL::SetShader() {
         // Set the texture samplers to correspond to different texture units
         GLuint uniform_tex = glGetUniformLocation(shader->shader.handle, "tex[0]");
         if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, 0);
+            glUniform1i(uniform_tex, TextureUnits::PicaTexture(0).id);
         }
         uniform_tex = glGetUniformLocation(shader->shader.handle, "tex[1]");
         if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, 1);
+            glUniform1i(uniform_tex, TextureUnits::PicaTexture(1).id);
         }
         uniform_tex = glGetUniformLocation(shader->shader.handle, "tex[2]");
         if (uniform_tex != -1) {
-            glUniform1i(uniform_tex, 2);
+            glUniform1i(uniform_tex, TextureUnits::PicaTexture(2).id);
         }
 
         // Set the texture samplers to correspond to different lookup table texture units
         GLuint uniform_lut = glGetUniformLocation(shader->shader.handle, "lighting_lut");
         if (uniform_lut != -1) {
-            glUniform1i(uniform_lut, 15);
+            glUniform1i(uniform_lut, TextureUnits::LightingLUT.id);
         }
 
         GLuint uniform_fog_lut = glGetUniformLocation(shader->shader.handle, "fog_lut");
         if (uniform_fog_lut != -1) {
-            glUniform1i(uniform_fog_lut, 9);
+            glUniform1i(uniform_fog_lut, TextureUnits::FogLUT.id);
         }
 
         GLuint uniform_proctex_noise_lut =
             glGetUniformLocation(shader->shader.handle, "proctex_noise_lut");
         if (uniform_proctex_noise_lut != -1) {
-            glUniform1i(uniform_proctex_noise_lut, 10);
+            glUniform1i(uniform_proctex_noise_lut, TextureUnits::ProcTexNoiseLUT.id);
         }
 
         GLuint uniform_proctex_color_map =
             glGetUniformLocation(shader->shader.handle, "proctex_color_map");
         if (uniform_proctex_color_map != -1) {
-            glUniform1i(uniform_proctex_color_map, 11);
+            glUniform1i(uniform_proctex_color_map, TextureUnits::ProcTexColorMap.id);
         }
 
         GLuint uniform_proctex_alpha_map =
             glGetUniformLocation(shader->shader.handle, "proctex_alpha_map");
         if (uniform_proctex_alpha_map != -1) {
-            glUniform1i(uniform_proctex_alpha_map, 12);
+            glUniform1i(uniform_proctex_alpha_map, TextureUnits::ProcTexAlphaMap.id);
         }
 
         GLuint uniform_proctex_lut = glGetUniformLocation(shader->shader.handle, "proctex_lut");
         if (uniform_proctex_lut != -1) {
-            glUniform1i(uniform_proctex_lut, 13);
+            glUniform1i(uniform_proctex_lut, TextureUnits::ProcTexLUT.id);
         }
 
         GLuint uniform_proctex_diff_lut =
             glGetUniformLocation(shader->shader.handle, "proctex_diff_lut");
         if (uniform_proctex_diff_lut != -1) {
-            glUniform1i(uniform_proctex_diff_lut, 14);
+            glUniform1i(uniform_proctex_diff_lut, TextureUnits::ProcTexDiffLUT.id);
         }
 
         current_shader = shader_cache.emplace(config, std::move(shader)).first->second.get();
@@ -1363,7 +1363,7 @@ void RasterizerOpenGL::SyncFogLUT() {
 
     if (new_data != fog_lut_data) {
         fog_lut_data = new_data;
-        glActiveTexture(GL_TEXTURE9);
+        glActiveTexture(TextureUnits::FogLUT.Enum());
         glTexSubImage1D(GL_TEXTURE_1D, 0, 0, 128, GL_RED_INTEGER, GL_UNSIGNED_INT,
                         fog_lut_data.data());
     }
@@ -1402,17 +1402,18 @@ static void SyncProcTexValueLUT(const std::array<Pica::State::ProcTex::ValueEntr
 }
 
 void RasterizerOpenGL::SyncProcTexNoiseLUT() {
-    SyncProcTexValueLUT(Pica::g_state.proctex.noise_table, proctex_noise_lut_data, GL_TEXTURE10);
+    SyncProcTexValueLUT(Pica::g_state.proctex.noise_table, proctex_noise_lut_data,
+                        TextureUnits::ProcTexNoiseLUT.Enum());
 }
 
 void RasterizerOpenGL::SyncProcTexColorMap() {
     SyncProcTexValueLUT(Pica::g_state.proctex.color_map_table, proctex_color_map_data,
-                        GL_TEXTURE11);
+                        TextureUnits::ProcTexColorMap.Enum());
 }
 
 void RasterizerOpenGL::SyncProcTexAlphaMap() {
     SyncProcTexValueLUT(Pica::g_state.proctex.alpha_map_table, proctex_alpha_map_data,
-                        GL_TEXTURE12);
+                        TextureUnits::ProcTexAlphaMap.Enum());
 }
 
 void RasterizerOpenGL::SyncProcTexLUT() {
@@ -1427,7 +1428,7 @@ void RasterizerOpenGL::SyncProcTexLUT() {
 
     if (new_data != proctex_lut_data) {
         proctex_lut_data = new_data;
-        glActiveTexture(GL_TEXTURE13);
+        glActiveTexture(TextureUnits::ProcTexLUT.Enum());
         glTexSubImage1D(GL_TEXTURE_1D, 0, 0, 256, GL_RGBA, GL_FLOAT, proctex_lut_data.data());
     }
 }
@@ -1444,7 +1445,7 @@ void RasterizerOpenGL::SyncProcTexDiffLUT() {
 
     if (new_data != proctex_diff_lut_data) {
         proctex_diff_lut_data = new_data;
-        glActiveTexture(GL_TEXTURE14);
+        glActiveTexture(TextureUnits::ProcTexDiffLUT.Enum());
         glTexSubImage1D(GL_TEXTURE_1D, 0, 0, 256, GL_RGBA, GL_FLOAT, proctex_diff_lut_data.data());
     }
 }
diff --git a/src/video_core/renderer_opengl/gl_state.cpp b/src/video_core/renderer_opengl/gl_state.cpp
index 40d7cee969..6ef6d6c4ce 100644
--- a/src/video_core/renderer_opengl/gl_state.cpp
+++ b/src/video_core/renderer_opengl/gl_state.cpp
@@ -183,7 +183,7 @@ void OpenGLState::Apply() const {
     // Textures
     for (unsigned i = 0; i < ARRAY_SIZE(texture_units); ++i) {
         if (texture_units[i].texture_2d != cur_state.texture_units[i].texture_2d) {
-            glActiveTexture(GL_TEXTURE0 + i);
+            glActiveTexture(TextureUnits::PicaTexture(i).Enum());
             glBindTexture(GL_TEXTURE_2D, texture_units[i].texture_2d);
         }
         if (texture_units[i].sampler != cur_state.texture_units[i].sampler) {
@@ -193,43 +193,43 @@ void OpenGLState::Apply() const {
 
     // Lighting LUTs
     if (lighting_lut.texture_buffer != cur_state.lighting_lut.texture_buffer) {
-        glActiveTexture(GL_TEXTURE15);
+        glActiveTexture(TextureUnits::LightingLUT.Enum());
         glBindTexture(GL_TEXTURE_BUFFER, cur_state.lighting_lut.texture_buffer);
     }
 
     // Fog LUT
     if (fog_lut.texture_1d != cur_state.fog_lut.texture_1d) {
-        glActiveTexture(GL_TEXTURE9);
+        glActiveTexture(TextureUnits::FogLUT.Enum());
         glBindTexture(GL_TEXTURE_1D, fog_lut.texture_1d);
     }
 
     // ProcTex Noise LUT
     if (proctex_noise_lut.texture_1d != cur_state.proctex_noise_lut.texture_1d) {
-        glActiveTexture(GL_TEXTURE10);
+        glActiveTexture(TextureUnits::ProcTexNoiseLUT.Enum());
         glBindTexture(GL_TEXTURE_1D, proctex_noise_lut.texture_1d);
     }
 
     // ProcTex Color Map
     if (proctex_color_map.texture_1d != cur_state.proctex_color_map.texture_1d) {
-        glActiveTexture(GL_TEXTURE11);
+        glActiveTexture(TextureUnits::ProcTexColorMap.Enum());
         glBindTexture(GL_TEXTURE_1D, proctex_color_map.texture_1d);
     }
 
     // ProcTex Alpha Map
     if (proctex_alpha_map.texture_1d != cur_state.proctex_alpha_map.texture_1d) {
-        glActiveTexture(GL_TEXTURE12);
+        glActiveTexture(TextureUnits::ProcTexAlphaMap.Enum());
         glBindTexture(GL_TEXTURE_1D, proctex_alpha_map.texture_1d);
     }
 
     // ProcTex LUT
     if (proctex_lut.texture_1d != cur_state.proctex_lut.texture_1d) {
-        glActiveTexture(GL_TEXTURE13);
+        glActiveTexture(TextureUnits::ProcTexLUT.Enum());
         glBindTexture(GL_TEXTURE_1D, proctex_lut.texture_1d);
     }
 
     // ProcTex Diff LUT
     if (proctex_diff_lut.texture_1d != cur_state.proctex_diff_lut.texture_1d) {
-        glActiveTexture(GL_TEXTURE14);
+        glActiveTexture(TextureUnits::ProcTexDiffLUT.Enum());
         glBindTexture(GL_TEXTURE_1D, proctex_diff_lut.texture_1d);
     }
 
diff --git a/src/video_core/renderer_opengl/gl_state.h b/src/video_core/renderer_opengl/gl_state.h
index d524d06250..bb02187080 100644
--- a/src/video_core/renderer_opengl/gl_state.h
+++ b/src/video_core/renderer_opengl/gl_state.h
@@ -6,6 +6,29 @@
 
 #include <glad/glad.h>
 
+namespace TextureUnits {
+
+struct TextureUnit {
+    GLint id;
+    constexpr GLenum Enum() const {
+        return static_cast<GLenum>(GL_TEXTURE0 + id);
+    }
+};
+
+constexpr TextureUnit PicaTexture(int unit) {
+    return TextureUnit{unit};
+}
+
+constexpr TextureUnit LightingLUT{3};
+constexpr TextureUnit FogLUT{4};
+constexpr TextureUnit ProcTexNoiseLUT{5};
+constexpr TextureUnit ProcTexColorMap{6};
+constexpr TextureUnit ProcTexAlphaMap{7};
+constexpr TextureUnit ProcTexLUT{8};
+constexpr TextureUnit ProcTexDiffLUT{9};
+
+} // namespace TextureUnits
+
 class OpenGLState {
 public:
     struct {