Reactivating Old Scene - 3

I had a lot of things which occupied me, so didn't do a lot of programming lately. The one thing I did was to look for the problems with the old scene and this took forever. The problems needed very, very long debugging runs and it took considerable time to find the problems. The first was a stupid cast, I had long ago cast a pointer to an unsigned long and later back. When the program was still 32bit it was no problem, but in the 64bit builds that caused a huge problem.

The second problem was, that I had swapped some transformations when I rebuilt a big part of the raytracer to make it fit for parallelization. And finally I had a little bug with dramatic effects. When a shadow hit was on a transparent face, then the hit information was lost. That resulted in the hit being treated as fully transparent, so I lost all shadows for transparent objects. That problem is also solved and I added an assert so I will find problems like that in the future much easier.

There is one problem remaining, the program crashes in a model when I switch antialiasing to higher levels. It seems to be about the same place in all runs, but it is hard to say, because the machine seems to run into heavy swapping and after quite some time the program silently closes and I never caught the last image. In debug builds it runs for hours until it would reach the spot. I didn't have the patience yet to find that bug.