Distorted Android

Postprocessing buffers mBuffer[] are now shared among all postprocessing operations. This saves a lot of memory, but also means that when doing each particular postprocessing, the textures backing up the mBuffer might be too large. We need to fix two things here: when outputting to those too large textures, we need to adjust the Viewport, and when binding those too large textures as input - we need to adjust the TexCoords to compensate....

Improve the 'PostprocessTree' app. Shows bugs in postprocessing.

Simplify postprocessing buffers.

Make the postprocessing buffers static.

A little progress making the postprocessing buffers static.

Introduce possibility that an OutputSurface is backed up by a larger texture than necessary and the 'cloneSize()' method.

SSBO: now we have a more-or-less correct running average of the count of transparent fragments over the last few frames.

SSBO: correct various things.

SSBO: zero out the per-surface transparent fragment counter only when setting the surface as output for the first time in the frame.

SSBO: handle the fact that we might run out of space in our SSBO if we keep creating new Surfaces.