SMOOTHING NORMALS FOR MR

Marco Splash

hey everyone! first post on polycount!

i got a lil problem with mentalray here... to be specific i think i've isolated this problem to the Arch and Design shader only.

i discovered reading EricChadwick's tutorial on normal maps that you can have great results when baking a highrez model on a lowrez geometry that contains some really large angle (by large angle and mean for example the 90degree angles of a cube) if you edit the smoothing groups and the uv seams correcly together: http://wiki.polycount.net/Normal_Map#TSVOS (read the "Shaders and Seams" part)... i know there is a post about that here but i completely lost track of it!

anyway my problem is that when i use arch and design in mentalray i dont have the beautiful results i get using raytrace, a standard material or even the 3ds max viewport!



you see that when using the arch and design shader, on some parts of the geometry the smoothing groups are ugly again. if i use something else than arch and design i get better results (similar to what i see in the viewport) EVEN IF I RENDER WITH MENTALRAY!

i dont know much about how normal maps work but i have the feeling it is related to what they call "tangent space"... maybe there is a way to play with the type of tangent space to get a result that looks good in mental ray's arch and design? or maybe it must be configured in 3dsmax/maya/whatever or even in xnormal (assuming you bake in xnormal)

i have tried object tangent as well but doesnt fix the problem.

can somebody help? cause i'd really like to do this project with the arch and design shader but i gotta fix this stupid problem!

thanks!

Emil Mujanovic

Moved this to Technical Talk

Rwolf

have you tryed rendering it without the normal map? does it yield the same results? (helps with trouble shooting the issue)

Tangent space is usually the best and most reliable way with MR. Of course make your bake out as tangent, and set the shader as tangent. Mixing diffrent types will usually result in unwanted effects.

Eric Chadwick

Since your end result is a render in Max, and not an output to a real-time engine, have you considered baking a displacement map for this instead of a normal map?

Besides, if you have a high-res source, why not just render using that, instead of baking to a low-res mesh?

r_fletch_r

or why not use the round corners shader if your just doing a render

Marco Splash

my goal is to make a mesh that would fit in a real time engine (in term of polycount and types of maps) but also make some beauty shots with a nice shader like with mental ray. in other words, i prefer to not use any displacement maps or options proper to a certain shader (like the "round corner" of arch and design). i understand ill probably have to change my tools since arch and design seems to be preferable for highpoly models...

if i had more time to finish my portfolio before school ends, I would try to have my model fully functional in realtime and not rely on rendered beauty shots to demonstrate my work... problem is i don't know any other realtime engines than Valve's source and I'm not really satisfied of it's potential

btw rwolf, i've tried to render it with the normal maps and it does the same thing unfortunately! ill try some other things and come back if i find anything!

thanks for your help!