This Cg example demonstrates the usage of CGbuffer using the CgGL runtime. Cg 2.0 
introduces the concept of bindable buffers to store program constants for fast
updates.

This example requires support of the OpenGL extension NV_parameter_buffer_object (PaBO).

Constant buffers (aka parameter buffers) are shared across the vertex pipeline, 
geometry pipeline and pixel pipeline. 

See the NV_parameter_buffer_object extension spec for more details about how these work.

This example draws three triangles, each colored differently by updating the CGbuffer
using the new cgSetBufferData and cgMapBuffer/cgUnmapBuffer API calls.
