//-----------------------------------------------------------------------------
// Offscreen rendering in OpenGL using framebuffer objects.
//
// Copyright 2015 <whitequark@whitequark.org>
//-----------------------------------------------------------------------------
#ifndef __GLOFFSCREEN_H
#define __GLOFFSCREEN_H

#include <stdint.h>

class GLOffscreen {
public:
    /* these allocate and deallocate OpenGL resources.
       an OpenGL context /must/ be current. */
    GLOffscreen();
    ~GLOffscreen();

    /* prepare for drawing a frame of specified size.
       returns true if OpenGL likes our configuration, false
       otherwise. if it returns false, the OpenGL state is restored. */
    bool begin(int width, int height);

    /* get pixels out of the frame and restore OpenGL state.
       the pixel format is ARGB32 with top row at index 0.
       the returned array is valid until the next call to begin() */
    uint8_t *end();

private:
    unsigned int _framebuffer;
    unsigned int _color_renderbuffer, _depth_renderbuffer;
    uint32_t *_pixels, *_pixels_inv;
    int _width, _height;
};

#endif