Question: I was looking for a way to detect the browser extension I am building from my website and I need to alert my users in-case they are viewing my site without it. I have been able to do this in firefox, but I want to know is there a way I can do this in Google Chrome? Even if there is a hack to get this going I am fine.

Answer: 
If it is in a texture:

* set up orthographic frustum
* disable blending, depth test, etc.
* bind texture
* draw screen-aligned textured quad with correct texture coordinates

I use this in for example in [Compositor::\_drawPixels](http://www.equalizergraphics.com/cgi-bin/viewvc.cgi/trunk/src/lib/client/compositor.cpp?revision=4207&view=markup)
glDrawPixels can read from a Buffer Object. Just do a 

```
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, XXX)

```

before calling glDrawPixels.

Caveat: glDrawPixels is deprecated...