Triangulation issue with brick shader


#1

Hi, I’m using ArchiCAD’s CineRender which is essentially a cut down version of Cinema4D, so this seems like a good place to post. I’m playing around with the Brick shader, and trying to get some convincing results when using it in conjunction with Displacement.

I’ve just done a test render and there seem to be some real oddities. The shadows between the bricks appear larger and blurred in certain areas (boxed in red). There’s also a weird diagonal artefact on the first floor. The wall is one consistent element, yet the change seems to be related to window position. I can only assume it’s something to do with how the wall is triangulated at render time.

Has anyone else had this? Is it a rendering setting that I’ve got wrong, or a bug of some sort? Any advice welcome!


#2

Looks like an UV issue to me. Try whether this happens with a flat or cubic projection.


#3

Unfortunately ArchiCAD doesn’t allow you to change mapping type (I believe) - just cubic as default.

I’ve tried pre-sub-dividing the face around the window openings, and it’s made a huge improvement. I guess the long triangles running along the whole building were the issue.


#4

Hm, if cubic is the default, that effect should not happen. The form of the polygons should not affect any regular projection (cubic, spherical, flat…) But who knows what transformations are done in the background…