[Fix] (Diligent/Shader): Rename glsl builtins for Vulkan.

MG/MG_GL/Implementations/EGL/Diligent/EGL_impl.cpp

@@ -371,6 +371,7 @@ namespace MG_Diligent {
 
                     shaderSource = MG_Util::Program::BindInputLayoutLocationsForGLSL(spirv,
                                                                                      programObj.attribLocations);
+                    MG_Util::Program::RenameGLSLBuiltinsForVulkan(shaderSource);
                 } else {
                     shaderSource = it->second.source;
                 }

MG/MG_GL/Implementations/GL/Program/GL_Program.cpp

@@ -277,6 +277,7 @@ namespace MG_GL::GL {
                     } else {
                         shaderSource = it->second.source;
                     }
+                    MG_Util::Program::RenameGLSLBuiltinsForVulkan(shaderSource);
                     shaderSources[it->first] = shaderSource;
                 }
             }

MG/MG_GL/State/Program/ProgramState.cpp

@@ -176,9 +176,25 @@ GLint ProgramState::QueryProgramAttributeLocation(GLuint program, const GLchar*
         GLint loc = it->second;
         MG_Util::Debug::LogD("MG_State: Program: QueryProgramAttributeLocation success: %s -> %d", name, loc);
         return loc;
+    } else {
+        MG_Util::Debug::LogW("MG_State: Program: QueryProgramAttributeLocation warning: name '%s' not found, generating new one...", name);
+        // Find the next available location
+        GLint loc = (GLint)prog.attribLocations.size();
+        bool locInUse;
+        do {
+            locInUse = false;
+            for (const auto& pair : prog.attribLocations) {
+                if (pair.second == loc) {
+                    locInUse = true;
+                    loc++;
+                    break;
+                }
+            }
+        } while (locInUse);
+        prog.attribLocations[name] = loc;
+        MG_Util::Debug::LogD("MG_State: Program: QueryProgramAttributeLocation success: %s -> %d", name, loc);
+        return prog.attribLocations[name];
     }
-    MG_Util::Debug::LogW("MG_State: Program: QueryProgramAttributeLocation warning: name '%s' not found", name);
-    return -1;
 }
 
 GLenum ProgramState::QueryProgramStateIntVector(GLuint program, GLenum pname, GLint* params) {

MG/MG_UTIL/Program/GLSLTool.cpp

@@ -5,8 +5,19 @@
 #include "GLSLTool.h"
 
 namespace MG_Util::Program {
-    std::string BindInputLayoutLocationsForGLSL(const std::vector<uint32_t>& spirv,
+    void RenameGLSLBuiltinsForVulkan(std::string &src) {
-                                                const MG_Global::unordered_map<std::string, GLint>&
+        static const std::vector<std::pair<std::regex, std::string>> rules = {
+                { std::regex(R"(\bgl_VertexID\b)"),   "gl_VertexIndex"    },
+                { std::regex(R"(\bgl_InstanceID\b)"), "gl_InstanceIndex"  }
+        };
+
+        for (auto &rule : rules) {
+            src = std::regex_replace(src, rule.first, rule.second);
+        }
+    }
+    
+    std::string BindInputLayoutLocationsForGLSL(std::vector<uint32_t>& spirv,
+                                                MG_Global::unordered_map<std::string, GLint>&
                                                         name_location_map) {
         spvc_context context = nullptr;
         spvc_parsed_ir ir = nullptr;
@@ -17,11 +28,13 @@ namespace MG_Util::Program {
         std::string output_glsl;
 
         if ((result = spvc_context_create(&context)) != SPVC_SUCCESS) {
+            MG_Util::Debug::LogE("[SPIRV-Cross] Failed to create context.");
             return {};
         }
 
         if ((result = spvc_context_parse_spirv(context, spirv.data(), spirv.size(), &ir)) != SPVC_SUCCESS) {
             spvc_context_destroy(context);
+            MG_Util::Debug::LogE("[SPIRV-Cross] Failed to parse SPIR-V.");
             return {};
         }
 
@@ -33,11 +46,13 @@ namespace MG_Util::Program {
                 &compiler
         )) != SPVC_SUCCESS) {
             spvc_context_destroy(context);
+            MG_Util::Debug::LogE("[SPIRV-Cross] Failed to create compiler.");
             return {};
         }
 
         if ((result = spvc_compiler_create_shader_resources(compiler, &resources)) != SPVC_SUCCESS) {
             spvc_context_destroy(context);
+            MG_Util::Debug::LogE("[SPIRV-Cross] Failed to create shader resources.");
             return {};
         }
 
@@ -50,6 +65,7 @@ namespace MG_Util::Program {
                 &num_inputs
         )) != SPVC_SUCCESS) {
             spvc_context_destroy(context);
+            MG_Util::Debug::LogE("[SPIRV-Cross] Failed to get stage inputs.");
             return {};
         }
 
@@ -61,8 +77,8 @@ namespace MG_Util::Program {
         for (const auto& [name, location] : name_location_map) {
             auto it = name_to_id.find(name);
             if (it == name_to_id.end()) {
-                spvc_context_destroy(context);
+                MG_Util::Debug::LogW("[SPIRV-Cross] Input name not found in shader: %s", name.c_str());
-                return {};
+                continue;
             }
 
             spvc_compiler_set_decoration(
@@ -81,6 +97,8 @@ namespace MG_Util::Program {
 
         if ((result = spvc_compiler_compile(compiler, &glsl_source)) != SPVC_SUCCESS) {
             spvc_context_destroy(context);
+            MG_Util::Debug::LogE("[SPIRV-Cross] Failed to compile to GLSL: %s",
+                                 spvc_context_get_last_error_string(context));
             return {};
         }
 

MG/MG_UTIL/Program/GLSLTool.h

@@ -182,9 +182,10 @@ namespace MG_Util::Program {
                                                                   std::string>& glslSources);
     void GenerateDefaultUBOForGLSL_Multi(
             MG_Global::unordered_map<GLuint, std::string> &shaderSources, std::vector<std::string>& outUniformBufferNames);
-    std::string BindInputLayoutLocationsForGLSL(const std::vector<uint32_t>& spirv,
+    std::string BindInputLayoutLocationsForGLSL(std::vector<uint32_t>& spirv,
-                                                const MG_Global::unordered_map<std::string, GLint>&
+                                                MG_Global::unordered_map<std::string, GLint>&
                                                         name_location_map);
+    void RenameGLSLBuiltinsForVulkan(std::string &src);
 }
 
 #endif //MOBILEGL_GLSLTOOL_H