[Feat] (GL_Drawing): Add DrawElementsSHITTILY. Add SPIRV->GLSL ES conversion.

MG/MG_UTIL/Program/GLSLTool.cpp

@@ -402,4 +402,39 @@ namespace MG_Util::Program {
         }
         spvc_context_destroy(context);
     }
+
+    std::string CompileSPIRVToGLSL(std::vector<unsigned int> spirv, uint glslVersion, bool isES) {
+        spvc_context context = nullptr;
+        spvc_parsed_ir ir = nullptr;
+        spvc_compiler compiler_glsl = nullptr;
+        spvc_compiler_options options = nullptr;
+        spvc_resources resources = nullptr;
+        const spvc_reflected_resource *list = nullptr;
+        const char *result = nullptr;
+        size_t count;
+
+        const SpvId *p_spirv = spirv.data();
+        size_t word_count = spirv.size();
+
+        spvc_context_create(&context);
+        spvc_context_parse_spirv(context, p_spirv, word_count, &ir);
+        spvc_context_create_compiler(context, SPVC_BACKEND_GLSL, ir, SPVC_CAPTURE_MODE_TAKE_OWNERSHIP, &compiler_glsl);
+        spvc_compiler_create_shader_resources(compiler_glsl, &resources);
+        spvc_resources_get_resource_list_for_type(resources, SPVC_RESOURCE_TYPE_UNIFORM_BUFFER, &list, &count);
+        spvc_compiler_create_compiler_options(compiler_glsl, &options);
+        spvc_compiler_options_set_uint(options, SPVC_COMPILER_OPTION_GLSL_VERSION, glslVersion);
+        spvc_compiler_options_set_bool(options, SPVC_COMPILER_OPTION_GLSL_ES, isES ? SPVC_TRUE : SPVC_FALSE);
+        spvc_compiler_install_compiler_options(compiler_glsl, options);
+        spvc_compiler_compile(compiler_glsl, &result);
+
+        if (!result) {
+            return{};
+        }
+
+        std::string essl = result;
+
+        spvc_context_destroy(context);
+
+        return essl;
+    }
 }