GLMixer Code

Implemented blending options: this required to introduce GLEW dependency under MSWindows (non-basic OpenGL functions), therefore the several changes in common.h and qmake file.

OpenGL optimizations (from RED BOOK). Most important is the use of glSubTexture2D to replace faster the content of a texture instead of glTexture2D which creates a new one.

Bug fix in the zoom, changed SOURCE_UNIT to smaller value (better for projection), and implemented zoom best fit for Mixing View.

Cmake feature; read the SVN repository HEAD revision and use it to show the revision number in the program.

Implemented GUI information for Capture and Rendering sources.

Made code compatible under Windows (GL_EXT_framebuffer_blit not in glext.h) by using Qt v4.6. + cleaned include dependency on the way.

Implemented capture of rendering output (+ create source and save to file). Added proper icons for source related actions and modified the menu a bit.

Implemented loopback Rendering output as source. It works with fbo and (if available) blitting of the fbo texture (to be fast).

Implemented mouse double click event

BIG OPENGL CLEANING: the manipulation view is not a ViewRenderWidget which implements the view changing mechanism, the OutputRenderWindow is now a OutputRenderWidget which implements the FBO blit extension, + many OpenGL and QGLWidget optimizations.