Development Journal of a Raytracer

I had written about posting pictures of the cat quite some days ago. Today I worked a bit on the cat and finally rendered some images. I think the results are not totally bad, although I am still missing some parts.

You probably can guess that there is no head and the forelegs are still missing. Currently I am still working on the hind legs. I think the basic form starts to look good, but there are still issues with it. I think that they are still a bit too thin from the side (or too thick from behind, probably the latter). In the second you can also see, that there are still problems around the hip.

But overall I am happy with the form. I think it resembles a cat quite well and with some additional tweaks it should be ok. I think I learned some things and I have fixed quite some bugs and added useful features to the program while working on this model.

I hope I can soon finish the hind legs, I will tweak the form a bit and then start on the paw. I will then start with the forelegs.

I think I have the main problems with lighting. I found some more bugs and some of the fixes had the effect to make hidden bugs become visible ones. That is, what had happened yesterday and caused the results to be completely useless. For example I had at one place used the wrong normal to find out, if a light has an effect and so I filtered out all the effective lights, while the noneffective ones resulted in reduced light (a term became negative). Another one was, that the default filter in the layered material implementation was completely opaque instead of completely transparent.

Now I have one more thing to check, I think the filtering function still doesn't work correctly with layered materials. The color I was seeing while debugging the code didn't seem correct to me. I will check and then finally start on the second half of the implementation for the layered materials.