Monday 24 January 2011

Level of detail and frame rates

I haven't posted for over a month.  I've made a lot of changes over that time but I have nothing to show for it!

My original aim was to have the ability to create large open vistas to play on.  My current level designs don't need them but it was a nice to have.  This works on the PC but with my current code the Xbox 360 cannot cope. 

I added some level of detail (LoD) reduction to the terrain and split it up in to chunks.  Unfortunatelly although I am pleased with the code it does not help much with the performance on the Xbox for large views.

For the Xbox I am going to have to restrict the viewing distance on the maps to about 80m.  The maps can still be large but will have more twists and turns in them.

I have removed the full Parallel Split Shadow mapping (PSSM) that I had and replaced it with just a single shadow map that fades out the shadows between 35 and 40m from the camera.  I am pleased with the look and very pleased with the frame rate.  I can maintain 60 FPS most of the time dropping to a still playable 30 FPS for short periods with more complex views.  It might need some adjustment when I get more models in the scenes but I am more confident that this is now workable.