 This example displays a scene containing a set of 50x50x50 SoAlgebraicShapes
 representing spheres having different radius linked by cylinders. 
 The instances are disposed following a regular geometrical pattern in space,
 inside a cube. The example shows how to customize the colors of the spheres
 by writing custom GPU shaders and how to link them the the existing shaders pipeline
 to integrate with OIV shadows and transparency shaders.
