Optimizations on game levels.

Just an update on the Doofus game and on what I have been working on for the past couple of weeks. The past couple of weeks have seen me seriously working at getting the triangle count down in the game levels. The tri count had been increasing steadily for the last few levels and it just started hitting on the FPS value real bad. That is why I had no option but to go for Triangle decimation. The amount of triangles for even moderately complex levels started turning out to be surprisingly high and most triangles were all but useless. The reason; Doofus 3D levels use brush based geometry and the tris are a result of successive CSG (Constructive Solid Geometry) splits. The more detail I added to the levels, the more redundant splits occurred with the brushes. Meaning the FPS started falling like a rock for arbitrarily complex levels.

The optimization technique I was working on reduces the number of triangles by a) Removing redundant vertices and b) Collapsing unwanted edges. Simple right, not quite. Triangle decimation turned out to be somewhat more complex than I had anticipated. Fortunately and after some real hard brainstorming I managed to get it working just as I wanted it to. Now in some situations the triangle count reduces to as much as 4%. But an average value of around 10 to 20 % is what I usually get. That is also quite significant to say the least. Thank God my effort has not been in vain after all. It was a real pain to get that working correctly. Check out the images below to actually see the optimizations at work.

Original scene.
A smaple Doofus 3D scene

Triangles in the unoptimized version (click to enlarge)
Triangles in the scene before optimization.

Triangles in the optimized version (click to enlarge)
Triangles in the same scene after optimization.

I have also been working on completing the AI. Sorry but I don’t have screens for those, maybe the next time. The AI still needs some amount of tweaking to get things working perfectly. I am not saying too much at this point in time; maybe in one of my next posts I will get into more details. Hopefully I can finish this last pending thing in the game soon.

One thought on “Optimizations on game levels.

  1. Pingback: Susheel’s Blog » Blog Archive » No more T-Junctions.

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