# DeferredShading #

This sample provides an example of deferred shading. It stores lighting attributes to various geometry buffers for performing lighting calculations in screen space.

### BACKGROUND ###

This example demonstrates deferred shading. In deferred shading, no shading is performed in the first pass of the vertex and pixel shaders. Shading is deferred until a second pass. On the first pass, information needed for shading (position, normal, depth, albedo) are rendered into the geometry buffer (G-buffer) as a series of textures. After this, a pixel shader computes the direct and indirect lighting at each pixel using the information of the texture buffers in screen space.

### USAGE ###

Press <1> to show the final image;  

Press <2> to show the position buffer;  

Press <3> to show the albedo buffer;  

Press <4> to show the normal buffer;  

Press <space> to toggle the model animation.

REQUIREMENTS

----------------------------------

### BUILD ###

OS X 10.10 SDK or later

### RUNTIME ###

OS X 10.8 or later

CHANGES FROM PREVIOUS VERSIONS:

----------------------------------

+ Version 2.0 

  - Updated to use OpenGL Core Profile

  - Updated to 10.10 SDK.

+ Version 1.1 

  - Moved shader setup to -prepareOpenGL to ensure that the OpenGL framebuffer is currently valid and thus avoid validation failure. . 

  - Replaced the NSTimer with a CVDisplayLink to drive the rendering loop.  

  - Added comments and cleaned up code.

+ Version 1.0 

  - First release

================================================================================

Copyright (C) 2008-2015 Apple Inc. All rights reserved.