search GLSL extensions

src/pch.h

@@ -20,6 +20,7 @@
         #include <OpenGLES/ES3/gl.h>
         #include <OpenGLES/ES3/glext.h>
         #define SHADER_VERSION "#version 300 es\n"
+        #define __GLES__ 1
         #define PP_OS "ios"
     #else
         #define __OSX__ 1
@@ -30,6 +31,7 @@
         #include <OpenGL/gl3.h>
         #include <OpenGL/gl3ext.h>
         #define SHADER_VERSION "#version 150\n"
+        #define __GL__ 1
         #define PP_OS "osx"
     #endif
 
@@ -52,6 +54,7 @@
 
     #define SHADER_VERSION "#version 300 es\n"
     #define PP_OS "android"
+    #define __GLES__ 1
     #define __block
     //#define STBI_NEON
     #define BT_SetTerminate void
@@ -75,6 +78,8 @@
     #include <openvr.h>
     #include <ppl.h>
 
+    #define __WIN__ 1
+    #define __GL__ 1
     #define SHADER_VERSION "#version 150\n"
     #define PP_OS "win"
     #define __block