GL.h

/***********************************************************************
    created:    Fri Jan 23 2009
    author:     Paul D Turner
*************************************************************************/
/***************************************************************************
 *   Copyright (C) 2004 - 2009 Paul D Turner & The CEGUI Development Team
 *
 *   Permission is hereby granted, free of charge, to any person obtaining
 *   a copy of this software and associated documentation files (the
 *   "Software"), to deal in the Software without restriction, including
 *   without limitation the rights to use, copy, modify, merge, publish,
 *   distribute, sublicense, and/or sell copies of the Software, and to
 *   permit persons to whom the Software is furnished to do so, subject to
 *   the following conditions:
 *
 *   The above copyright notice and this permission notice shall be
 *   included in all copies or substantial portions of the Software.
 *
 *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 *   IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 *   OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 *   ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 *   OTHER DEALINGS IN THE SOFTWARE.
 ***************************************************************************/
#ifndef _CEGUIOpenGL_h_
#define _CEGUIOpenGL_h_

#include "CEGUI/Config.h"

#if defined CEGUI_USE_EPOXY

#include <epoxy/gl.h>

#elif defined CEGUI_USE_GLEW

#include <GL/glew.h>

// When using GLEW, there's no need to "#include" the OpenGL headers.
#ifndef __APPLE__
#   if (defined( __WIN32__ ) || defined( _WIN32 ))
#       include <windows.h>
#   endif
#   include <GL/glu.h>
#else
#   include <OpenGL/glu.h>
#endif

#else
#error Either "CEGUI_USE_EPOXY" or "CEGUI_USE_GLEW" must be defined. Defining both or none is invalid.
#endif

#ifndef GL_RGB565
#define GL_RGB565  0x8D62
#endif

#if (defined( __WIN32__ ) || defined( _WIN32 )) && !defined(CEGUI_STATIC)
#   if defined(CEGUIOPENGLRENDERER_EXPORTS) || defined(CEGUIOPENGLES2RENDERER_EXPORTS)
#       define OPENGL_GUIRENDERER_API __declspec(dllexport)
#   else
#       define OPENGL_GUIRENDERER_API __declspec(dllimport)
#   endif
#else
#   define OPENGL_GUIRENDERER_API
#endif

namespace CEGUI {

class OPENGL_GUIRENDERER_API OpenGLInfo
{

public:
    enum Type
    {
        TYPE_NONE, 
        TYPE_DESKTOP, 
        TYPE_ES 
    };

    static OpenGLInfo& getSingleton() { return s_instance; }

    void init();
    
    Type type() const { return d_type; }
    
    bool isUsingDesktopOpengl() const { return type() == TYPE_DESKTOP; }
    
    bool isUsingOpenglEs() const { return type() == TYPE_ES; }

    GLint verMajor() const { return d_verMajor; }
    
    GLint verMinor() const { return d_verMinor; }

    bool verAtLeast(GLint major, GLint minor) {
        return verMajor() > major  ||  (verMajor() == major && verMinor() >= minor); }

    bool isS3tcSupported() const { return d_isS3tcSupported; }

    bool isNpotTextureSupported() const { return d_isNpotTextureSupported; }

    bool isReadBufferSupported() const
      { return d_isReadBufferSupported; }

    bool isPolygonModeSupported() const
      { return d_isPolygonModeSupported; }

    bool isVaoSupported() const { return d_isVaoSupported; }

    bool isSeperateReadAndDrawFramebufferSupported() const
      { return d_isSeperateReadAndDrawFramebufferSupported; }

    bool isSizedInternalFormatSupported() const
      { return d_isSizedInternalFormatSupported; }

    /* For internal use. Used to force the object to act is if we're using a
       context of the specificed "verMajor_.verMinor_". This is useful to
       check that an OpenGL (desktop/ES) version lower than the actual one
       works correctly. Of course, this should work only if the actual
       version is compatible with the forced version. For example this can be
       used to check OpenGL ES 2.0 when the context is actually OpenGL ES 3.0
       (which is compatible with OpenGL ES 2.0). */
    void verForce(GLint verMajor_, GLint verMinor_);
      
private:

    static OpenGLInfo s_instance;
    OpenGLInfo();
    void initTypeAndVer();
    void initSupportedFeatures();
    
    Type d_type;
    GLint d_verMajor;
    GLint d_verMinor;
    GLint d_verMajorForce;
    GLint d_verMinorForce;
    bool d_isS3tcSupported;
    bool d_isNpotTextureSupported;
    bool d_isReadBufferSupported;
    bool d_isPolygonModeSupported;
    bool d_isSeperateReadAndDrawFramebufferSupported;
    bool d_isVaoSupported;
    bool d_isSizedInternalFormatSupported;
};

} // namespace CEGUI

#endif  // end of guard _CEGUIOpenGL_h_