ref: add export that returns GL_GetProcAddress for renderapi

engine/client/cl_render.c

@@ -252,7 +252,7 @@ static render_api_t gRenderAPI =
 	NULL, // GL_TexGen,
 	NULL, // GL_TextureTarget,
 	NULL, // GL_SetTexCoordArrayMode,
-	GL_GetProcAddress,
+	NULL, // GL_GetProcAddress,
 	NULL, // GL_UpdateTexSize,
 	NULL,
 	NULL,
@@ -309,6 +309,7 @@ static void R_FillRenderAPIFromRef( render_api_t *to, const ref_interface_t *fro
 	to->GL_DrawParticles         = from->GL_DrawParticles;
 	to->LightVec                 = from->LightVec;
 	to->StudioGetTexture         = from->StudioGetTexture;
+	to->GL_GetProcAddress        = from->R_GetProcAddress;
 }
 
 /*

engine/ref_api.h

@@ -583,6 +583,8 @@ typedef struct ref_interface_s
 	void		(*R_NewMap)( void );
 	// clear the render entities before each frame
 	void		(*R_ClearScene)( void );
+	// GL_GetProcAddress for client renderer
+	void*		(*R_GetProcAddress)( const char *name );
 
 	// TriAPI Interface
 	// NOTE: implementation isn't required to be compatible

ref_gl/gl_context.c

@@ -332,6 +332,16 @@ qboolean R_SetDisplayTransform( ref_screen_rotation_t rotate, int offset_x, int
 	return ret;
 }
 
+static void* GAME_EXPORT R_GetProcAddress( const char *name )
+{
+#ifdef XASH_GL4ES
+	extern void *gl4es_GetProcAddress( const char *name );
+	return gl4es_GetProcAddress( name );
+#else // TODO: other wrappers
+	return gEngFuncs.GL_GetProcAddress( name );
+#endif
+}
+
 static const char *R_GetConfigName( void )
 {
 	return "opengl";
@@ -453,6 +463,7 @@ ref_interface_t gReffuncs =
 	Mod_GetCurrentVis,
 	R_NewMap,
 	R_ClearScene,
+	R_GetProcAddress,
 
 	TriRenderMode,
 	TriBegin,
@@ -503,6 +514,8 @@ void EXPORT GetRefHumanReadableName( char *out, size_t size )
 	Q_strncpy( out, "GLES1(NanoGL)", size );
 #elif defined XASH_WES
 	Q_strncpy( out, "GLES2(gl-wes-v2)", size );
+#elif defined XASH_GL4ES
+	Q_strncpy( out, "GLES2(gl4es)", size );
 #else
 	Q_strncpy( out, "OpenGL", size );
 #endif