[Feat] (Shader): Add MobileGlues macro injection in GLSL preprocessor.

README.md

@@ -2,6 +2,40 @@
 
 **MobileGlues**, which stands for "(on) Mobile, GL uses ES", is a GL implementation running on top of host OpenGL ES 3.x (best on 3.2, minimum 3.0), with running Minecraft: Java Edition in mind.
 
+# For Shader Developers
+
+1. MobileGlues automatically:
+   - Converts desktop GLSL → GLSL ES
+   - Removes `layout(binding)` syntax
+   - Handles version directives
+   - Always declare precision explicitly:
+     ```glsl
+     precision highp float;
+     precision highp int;
+     ```
+
+2. MobileGlues (since V1.2.6.0) injects these macros into your shaders:
+   ```glsl
+   #define MG_MOBILEGLUES                   // Indicates MobileGlues environment
+   #define MG_MOBILEGLUES_VERSION 1260      // Version number (e.g. 1260 = V1.2.6)
+   ```
+
+   Use these macros for platform-specific logic:
+   ```glsl
+   #ifdef MG_MOBILEGLUES
+       #if MG_MOBILEGLUES_VERSION >= 1270
+           // Logic for MobileGlues (version >= V1.2.7)
+       #else
+		   // Logic for MobileGlues (version < V1.2.7)
+       #endif
+   #else
+       // ...
+   #endif
+   ```
+
+3. If encountering issues:
+   - Enable `Ignore shader/program error`, and check the logs (located at `/sdcard/MG/latest.log`).
+
 # License
 
 MobileGlues is licensed under **GNU LGPL-2.1 License**.

src/main/cpp/gl/glsl/glsl_for_es.cpp

@@ -525,6 +525,28 @@ vec4 GI_TemporalFilter() {
     glsl.insert(main_loc, "\n" + GI_TemporalFilter + "\n");
 }
 
+void inject_mg_macro_definition(std::string& glslCode) {
+    std::stringstream macro_stream;
+    macro_stream << "\n#define MG_MOBILEGLUES\n"
+                 << "#define MG_MOBILEGLUES_VERSION "
+                 << MAJOR << MINOR << REVISION << PATCH << "\n";
+    std::string macro_definitions = macro_stream.str();
+
+    size_t lastExtensionPos = glslCode.rfind("#extension");
+    size_t insertionPos = 0;
+
+    if (lastExtensionPos != std::string::npos) {
+        size_t nextNewline = glslCode.find('\n', lastExtensionPos);
+        insertionPos = (nextNewline != std::string::npos) ? nextNewline + 1 : glslCode.length();
+    } else {
+        size_t firstNewline = glslCode.find('\n');
+        insertionPos = (firstNewline != std::string::npos) ? firstNewline + 1 : 0;
+    }
+
+    glslCode.insert(insertionPos, macro_definitions);
+}
+
+
 std::string preprocess_glsl(const std::string& glsl) {
     std::string ret = glsl;
     // Remove lines beginning with `#line`
@@ -540,10 +562,13 @@ std::string preprocess_glsl(const std::string& glsl) {
 
     // GI_TemporalFilter injection
     inject_temporal_filter(ret);
-
+    
     // textureQueryLod injection
     inject_textureQueryLod(ret);
 
+    // MobileGlues macros injection
+    inject_mg_macro_definition(ret);
+
     return ret;
 }
 

src/main/cpp/gles/loader.cpp

@@ -145,10 +145,6 @@ void InitGLESCapabilities() {
     GLES.glGetIntegerv(GL_MAJOR_VERSION, &g_gles_caps.major);
     GLES.glGetIntegerv(GL_MINOR_VERSION, &g_gles_caps.minor);
 
-//    int has_GL_EXT_buffer_storage = 0;
-//    int has_GL_ARB_timer_query = 0;
-//    int has_GL_QCOM_texture_lod_bias = 0;
-
     GLint num_es_extensions = 0;
     GLES.glGetIntegerv(GL_NUM_EXTENSIONS, &num_es_extensions);
     LOG_D("Detected %d OpenGL ES extensions.", num_es_extensions)
@@ -184,6 +180,8 @@ void InitGLESCapabilities() {
                 g_gles_caps.GL_EXT_texture_norm16 = 1;
             } else if (strcmp(extension, "GL_EXT_texture_rg") == 0) {
                 g_gles_caps.GL_EXT_texture_rg = 1;
+            } else if (strcmp(extension, "GL_EXT_texture_query_lod") == 0) {
+                g_gles_caps.GL_EXT_texture_query_lod = 1;
             }
         } else {
             LOG_D("(nullptr)")

src/main/cpp/gles/loader.h

@@ -157,6 +157,7 @@ struct gles_caps_t {
     int GL_OES_depth_texture_float;
     int GL_EXT_texture_norm16;
     int GL_EXT_texture_rg;
+    int GL_EXT_texture_query_lod;
 };
 
 extern struct gles_caps_t g_gles_caps;