Use Irrlicht bindings for GL call

src/client/shader.cpp

@@ -40,20 +40,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "client/tile.h"
 #include "config.h"
 
-#if ENABLE_GLES
-#ifdef _IRR_COMPILE_WITH_OGLES1_
-#include <GLES/gl.h>
-#else
-#include <GLES2/gl2.h>
-#endif
-#else
-#ifndef __APPLE__
-#include <GL/gl.h>
-#else
-#define GL_SILENCE_DEPRECATION
-#include <OpenGL/gl.h>
-#endif
-#endif
+#include <mt_opengl.h>
 
 /*
  A cache from shader name to shader path
@@ -667,13 +654,19 @@ ShaderInfo ShaderSource::generateShader(const std::string &name,
  )";
  }
 
+ // Since this is the first time we're using the GL bindings be extra careful.
+ // This should be removed before 5.6.0 or similar.
+ if (!GL.GetString) {
+ errorstream << "OpenGL procedures were not loaded correctly, "
+ "please open a bug report with details about your platform/OS." << std::endl;
+ abort();
+ }
+
  bool use_discard = use_gles;
-#ifdef __unix__
  // For renderers that should use discard instead of GL_ALPHA_TEST
- const char* gl_renderer = (const char*)glGetString(GL_RENDERER);
- if (strstr(gl_renderer, "GC7000"))
+ const char *renderer = reinterpret_cast<const char*>(GL.GetString(GL.RENDERER));
+ if (strstr(renderer, "GC7000"))
  use_discard = true;
-#endif
  if (use_discard) {
  if (shaderinfo.base_material == video::EMT_TRANSPARENT_ALPHA_CHANNEL)
  shaders_header << "#define USE_DISCARD 1\n";