Alternative for glBlitFrameBuffer() in OpenGL ES 2.0

Question

My Android program must use glBlitFrameBuffer() function to copy FrameBuffer object. But glBlitFrameBuffer() function is only supported on OpenGL ES 3.0+ devices. I want to support OpenGL ES 2.0+ devices.

Is there any solution/alternative for this function?

Answer 1

1. Bind texture that used as collor attachment on source frame buffer
2. Bind destination framebuffer
3. Draw full screen quad (if you need stretch or offseted reading manipulate with vertex/tex coordinates)
4. Fetch data from bound texture in frament shader and put it to gl_FragColor