CG Madness is based on the classic game Marble Madness. It is running on OpenGL and uses current CG techniques like light maps, bump-mapping and reflection shader. It also has an editor where you can create your own levels. If you have done so and you want to share the level, you can upload it.
About the portals modification
In the extension "CG Portals" you will be able to throw Portals towards walls and/or floors, so you can reach unreachable places.
CG Madness Puzzle
A logic browser game based on the setting of CG Madness. Play Now