Ya'll: I've been experimenting with Bas Relief by making images of terrains from directly overhead, looking straight down. The terrain and the sides of the viewing frustum are parallel. What happens is I get a white cross in the rendering. The height of the terrain doesn't matter, with a procedural texture, I still get a white cross in the image. Interestingly, the ray tracer refines the white striping as it progressively moves to finer and finer resolution. Any one know anything about this? Thanks

It's Vue 4 bug. I've seen these lines many times. It occurs when the camera angle is divisible by 90. Set the camera angle to 180.05, and see if the lines are still there.

Charles

Hey, thanks! I'll do that. Hmmm. Ya know, I get this - likely rotation matrix singularity, tan2(), etc. Good call. Sitting Blue; aren't you the one who made that very nice terrain mapping tutorial, the one that I have studied in detail? (Thanks AGAIN!) You might want to check out my last two posts which are somewhat successful attempts finally at getting terrain mapping working. In the first (W'fall VUE) I describe my scaling attempts a bit. The second, "Urban Aorta" has all scaling set at one and accomplishes the same thing via a different route: 1: Create terrain, set resolution, flatten (z height = 0) and fit aspect ratio. 2: Create texture for the terrain, Object-Standard, flat. Make sure texture is positioned exactly on terrain as you want it. Bump Gain = 0; optional. 3: Position camera directly overhead and adjust until terrain/texture fits camera precisely. (Should like a photograph) 3: Render, and save image. 4: Open saved image in terrain. Now as you change the terrain height to non-zero, the texture sits exactly registered on the terrain (subject of course to how well you did #2 above (use a pocket calculator to do the trig.) - Clark