Bump Maps and GI

[ADaugirdas]

Why does a bump map not appear when you switch from direct lighting to global illumination? For instance, when i apply a bump mapped material to an object, and render using the default.visopt settings which i believe use the sun and sky. if i switch to one of the gi presets, the bump map disappears.

i've read somewhere that because a surface is being lit equally from all sides, the bump can't function. i have trouble believing that bump maps don't work with gi at all..

[Jackson_cg]

Re: Bump Maps and GI

If the effect of a bump map depends on directional lighting (i.e. lighting which reveals the "bumps" in the surface) how can a bump map function satisfactorily if the lighting is uniform, i.e. non-directional? It's the same in rendering as it is in the "real world" or photography- it's all in the lighting.

If the default visopt doesn't render bump maps the way you'd like, then use another visopt or change it. Defaults are rarely perfect, that's why they're called "default".