Quite a few things wrong here:
* Mac did not support EXT_draw_instanced, only ARB_draw_instanced
* Draw instanced did not work unless data came from vertex buffer, which
is second time we see weird things with vertex arrays in mac
* There were a few stupid mistakes by me as well, such as binding to
uniform locations for the wrong shaders (it's a wonder it ever worked
:p)
A new checkbox "High quality" is provided in camera settings to enable
this. This creates a depth of field that is much closer to the rendered
result and even supports aperture blades in the effect, but it's more
expensive too. There are optimizations to do here since the technique is
very fill rate heavy.
People, be careful, this -can- lock up your screen if depth of field
blurring is too extreme.
Technical details:
This uses geometry shaders + instancing and is an adaptation of
techniques gathered from
http://bartwronski.com/2014/04/07/bokeh-depth-of-field-going-insane-http://advances.realtimerendering.com/s2011/SousaSchulzKazyan%20-
%20in%20Real-Time%20Rendering%20Course).ppt
TODOs:
* Support dithering to minimize banding.
* Optimize fill rate in geometry shader.
* Rename functions and move to own header.
* Add wrapper functions for glLight.
* Auto detect if we can use faster code for solid lighting.
* Various fixes for textured draw mode.
