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Quake 3: Ray traced

In 2004 I started working on one of the first raytracing computer games as my student research project. As a base for this project the content from “Quake 3� was used. It was amazing how easy it was to program special effects that would have taken much longer using the conventional graphic technology called “rasterization� used by common graphic cards. For example dynamic, per-pixel real-time shadows are calculated with about ten lines of code as described in the introduction figure about ray tracing.

(Shadows in Quake 3: Ray traced (2004))

Generating shadows without disturbing artifacts is still a problem in many games, though some games have done it right. Here some of the bad examples from games, all released in 2006:

 
(“Gothic 3� (2006) Shadows

(“The Lord of the Rings: The Battle for Middle-earth II� from 2006)

(“Call of Juarez� from 2006)

Another advantage of ray tracing is that you can use many more polygons to render a scene without a dramatic performance impact compared to the rasterization approach. So I “pimped up� some of the walls and floors in Quake 3 to see how well it performs. Instead of two triangles for a wall I used 5,000.

(Using 5,000 triangles instead of 2.)

(The replaced walls in game. The real geometric displacement can be seen from any perspective.)

The result was: while the geometry complexity of the Quake 3 Level was six times higher, the frame rate dropped only to about ¾ of its original value.

Other special effects in Quake 3: Ray traced (http://www.q3rt.de/) are glass, mirrors in mirrors, camera portals and ground fog.

To see Quake 3: Ray traced in action you can look at these two videos:

Q3RT Video 1: Mirror Idfun.de | Mirror FileShack

Q3RT - Video 2: Mirror Idfun.de | Mirror FileShack

Next Page - Quake 4: Ray traced

Review Index:
- Select - Introduction to Ray Tracing Quake 3: Ray traced Quake 4: Ray traced Performance and Conclusions