I use rpict to render a daylit spaces with a window installed a blind. I used rpict to render it and found the shadow on the ground are irregularity. I also tried to bump up the -ad and reduce -aa , but even I set -aa as 0 to disable indirect cache, it has no improvement. But when use rpict, I got a very regular shadow.
Below are HDR images rendered by rpict and rtrace, respectively.
Left: rpict -vf Views/view.vf -x 600 -y 600 -aa 0.1 -dc 1 -dt 0 -dj 0 -lw 1e-3 -ab 5 -ad 1000
Right: rtrace -n 16 -vf Views/view.vf -x 600 -y 600 -aa 0.1 -dc 1 -dt 0 -dj 0 -lw 1e-3 -ab 5 -ad 1000
The shadows are created by the direct calculation, so any change of any parameters on the ambient calculation will not help.
I guess it is the pixel sampling which should be set to 1 (-ps 1). In addition, I would recommend to lower -lw significantly otherwise the ray termination is too early (e.g. -lw 1e-6).
hope that helps
Jan
You must be using “rtpict” not “rtrace” in your example. Jan is correct that the -ps option in rpict should be set to 1 to avoid image-plane sampling in this case. The rtpict command ignores the -ps option and always uses -ps 1 because it does not implement this feature, which saves time in many situations while producing reasonably accurate results. The indirect calculation is not the one with problems in your test.
