#1 two patches for linux

[Florian Kirsch]

Hi,

below I have attached two patches for
rendertexture-2.0.3 that you might possible want to
apply. My changes are marked with [Florian].

1. Querying the color format of the pbuffer for linux
was not yet implemented. I have implemented this; my
solution works well on NVidia hardware for integer
color buffers. I am unsure of results with float buffer
(I am currently not able to test float buffers)

2. Under linux, pbuffers were always created with
double buffering. To force a single buffered pbuffer, I
have added the option "singlebuffer" (resp. "single".

Yours, Florian

[Florian Kirsch]

[Florian Kirsch]

only documentation changes here