In The Witness we decided that it’s a good idea to have a heightfield terrain making up the bulk of the island surface.  The advantages of this are in rendering performance and in ease of texturing (it is relatively easy, with one continuously-parameterized terrain block, to get rid of seams; if your terrain is a [...]

In the previous part, I talked about my reasons for wanting to use Cascading Shadow Maps (one of the biggest: image stability), then said that we had implemented Michal Valient’s version of the algorithm, and mostly liked it, but wanted to reduce the memory usage.
This time I’ll show how to reduce the memory usage by 25% [...]

As explained by Jon in his previous post, we are using precomputed global illumination in The Witness, and one of my first tasks was to work on that system.
I have developed some interesting technology to compute automatic paramaterizations, to formulate the lighting computations in a way that can be easily mapped to the GPU, and [...]

It seems like time to post some images from the in-progress precoputed lighting tech that Ignacio is working on.  See here for a description of the basics behind what we are doing for lighting.  The lightmaps are now 16-bit and these shots use a simple exponential tone mapper.
First, I’ve taken shots from 3 positions inside [...]

The Witness contains a mixture of indoor and outdoor scenes, but much of the game takes place outdoors with a very long view distance (you can see the entire island at once if you have a good vantage point).  So I wanted to implement a shadow system that would work robustly, provide high visual quality, [...]