bump map problem

[skogskalle]

howdy!

I know there are tons of threads about bump-maps not showing up when using a uniform skylight and stuff... but I think my problem is a little different.

the bumpmap shows... but it has weird flaws all over. take a look at the attached image.

1. - theres a green mark just under the egde of the roof.... where did it come from??

2. lots of these artifacts... the bumped area switches between light and dark. why?

using the latest beta build. The scene lighting is a light blue environment, and a light yellow direct spot with Vray shadows. The bumpmap is a "gradient ramp" map.

Gi is IRRmap for first, and Lightmap for second bounce.
AA method is Adaptive subdivisions at 0 - 2

thanks in advance! any help appreciated! if you need more info, just ask...

[Dra(hen]

One thing you can try is upping your prepasses. Like try using -3 to -0 or something like that.

[skogskalle]

thanks for the reply!

after upping the IRRmap settings and also raising the Lightmap subdivs from 500 to 4000 (!) it looks much better... not perfect, but good enough... if I had the time Id use displacement instead, but there are lots of other displaced geomentry in the scene and the rendertimes are already getting high...