/*!****************************************************************************

 @file         OGLES3/PVRTgles3Ext.h
 @ingroup      API_OGLES3
 @copyright    Copyright (c) Imagination Technologies Limited.
 @brief        OpenGL ES 3.0 extensions

******************************************************************************/
#ifndef _PVRTgles3Ext_H_
#define _PVRTgles3Ext_H_

/*!
 @addtogroup   API_OGLES3
 @{
*/

#if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE==1
#import  <OpenGLES/ES3/gl.h>
#import  <OpenGLES/ES3/glext.h>
// No binary shaders are allowed on the iphone and so this value is not defined
// Defining here allows for a more graceful fail of binary shader loading at runtime
// which can be recovered from instead of fail at compile time
#define GL_SGX_BINARY_IMG 0
#else
#ifdef BUILD_OGLES31
	#include <GLES3/gl31.h>
#else
	#include <GLES3/gl3.h>
#endif
#endif

#if !defined(EGL_NOT_PRESENT)
#define PVRGetProcAddress(x) eglGetProcAddress(#x)
#endif

/****************************************************************************
** Build options
****************************************************************************/

#define GL_PVRTGLESEXT_VERSION 3

/**************************************************************************
****************************** GL EXTENSIONS ******************************
**************************************************************************/

/*!**************************************************************************
 @class         CPVRTgles3Ext
 @brief         A class for initialising and managing OGLES3 extensions
****************************************************************************/
class CPVRTgles3Ext
{
public:
    // typedef definition for pointers to functions returned by eglGetProcAddress
    typedef void (GL_APIENTRYP PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXT)(GLenum, GLsizei, GLenum, GLsizei, GLsizei);
    typedef void (GL_APIENTRYP PFNGLFRAMEBUFFERTEXTURE2DMULTISAMPLEEXT)(GLenum, GLenum, GLenum, GLuint,GLint, GLsizei);
    
    typedef void (GL_APIENTRYP PFNGLRENDERBUFFERSTORAGEMULTISAMPLEIMG)(GLenum, GLsizei, GLenum, GLsizei, GLsizei);
    typedef void (GL_APIENTRYP PFNGLFRAMEBUFFERTEXTURE2DMULTISAMPLEIMG)(GLenum, GLenum, GLenum, GLuint,GLint, GLsizei);
    
    // GL_IMG_multisampled_render_to_texture
#if !defined(GL_IMG_multisampled_render_to_texture)
#define GL_RENDERBUFFER_SAMPLES_IMG                 0x9133
#define GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE_IMG   0x9134
#define GL_MAX_SAMPLES_IMG                          0x9135
#define GL_TEXTURE_SAMPLES_IMG                      0x9136
#endif
    
    // GL_EXT_multisampled_render_to_texture
#if !defined(GL_EXT_multisampled_render_to_texture)
#define GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_SAMPLES_EXT           0x8D6C
#define GL_RENDERBUFFER_SAMPLES_EXT                             0x8CAB
#define GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE_EXT               0x8D56
#define GL_MAX_SAMPLES_EXT                                      0x8D57
#endif
    
    PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXT glRenderbufferStorageMultisampleEXT;
    PFNGLRENDERBUFFERSTORAGEMULTISAMPLEIMG glRenderbufferStorageMultisampleIMG;
    PFNGLFRAMEBUFFERTEXTURE2DMULTISAMPLEEXT glFramebufferTexture2DMultisampleEXT;
    PFNGLFRAMEBUFFERTEXTURE2DMULTISAMPLEIMG glFramebufferTexture2DMultisampleIMG;
    
	/*!***********************************************************************
	@brief		Initialises IMG extensions
	*************************************************************************/
	void LoadExtensions();

	/*!***********************************************************************
	@brief		Queries for support of an extension
	@param[in]	extension    Extension to query for
	@return		True if the extension is supported
	*************************************************************************/
	static bool IsGLExtensionSupported(const char * const extension);
};

/*! @} */

#endif /* _PVRTgles3Ext_H_ */

/*****************************************************************************
 End of file (PVRTgles3Ext.h)
*****************************************************************************/