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HitmonDavis
11-06-2009, 03:29 PM
I'm working on a game-rez scifi rifle. I have a lot of detail in the high poly to transfer to the low poly. I am running into trouble with the holes with bolts in them. I've discovered it is tricky to make a normal map if there are perpendicular normals between the two meshes, so I've beveled all the holes and bolts to have some depth to them.

I'm still having a hard time with the bolts. I've used Maya, Xnormal, and Zbrush to transfer maps, but all of them have problems with the bolts. There is a lot of room for fine tuning in the Zbrush settings, I was thinking that might do the trick if I had the right settings.

Any help is much appreciated.

Low:
http://i8.photobucket.com/albums/a3/barstoolracer/low.jpg

High:
http://i8.photobucket.com/albums/a3/barstoolracer/high.jpg

I could patch it up in photoshop, but that's just one segment of the gun, there are a lot more.

slipmaggot75
11-06-2009, 06:40 PM
I believe that you need to increase your raycasting units.

Piflik
11-07-2009, 11:12 AM
The problem with skewed details comes from the Cage. The Rays are cast from a Mesh-Vertex to the corresponding Vertex on the Cage and so they are neccessarily not perpendicular to the surface, leading to skewed Normals.Try baking a second Normal Map without a Cage and the combine them in PS (in general the one with a Cage has better edges, the one without is better at detail...)

To get rid of the pixelation, increase number of Rays cast and/or the texture size (if possible).

HitmonDavis
11-07-2009, 05:43 PM
The problem with skewed details comes from the Cage. The Rays are cast from a Mesh-Vertex to the corresponding Vertex on the Cage and so they are neccessarily not perpendicular to the surface, leading to skewed Normals.Try baking a second Normal Map without a Cage and the combine them in PS (in general the one with a Cage has better edges, the one without is better at detail...)

To get rid of the pixelation, increase number of Rays cast and/or the texture size (if possible).

Cool. That actually makes a lot of sense, because my low poly is pretty bare. I'll give it a shot. Thanks!

HitmonDavis
11-07-2009, 09:59 PM
The problem with skewed details comes from the Cage. The Rays are cast from a Mesh-Vertex to the corresponding Vertex on the Cage and so they are neccessarily not perpendicular to the surface, leading to skewed Normals.Try baking a second Normal Map without a Cage and the combine them in PS (in general the one with a Cage has better edges, the one without is better at detail...)

To get rid of the pixelation, increase number of Rays cast and/or the texture size (if possible).

Alright, I tried that out, worked great. Thanks for the help.

biggestkid
11-11-2009, 09:51 AM
Hmm this has struck a question in my mind. Does increasing the number of rays cast have any negative effects to it? As opposed to its positive effects of producing a better normal map.

Also, how can i increase the number of rays cast for my normal maps?

Kien
11-11-2009, 11:24 PM
The problem with skewed details comes from the Cage. The Rays are cast from a Mesh-Vertex to the corresponding Vertex on the Cage and so they are neccessarily not perpendicular to the surface, leading to skewed Normals.Try baking a second Normal Map without a Cage and the combine them in PS (in general the one with a Cage has better edges, the one without is better at detail...)
I have been thinking about these skewed problems as well and they annoy me. How do you bake without a cage?? :S Preferably in max or maya. The only method I know is to separate the flat areas that are supposed to have the details and bake just them so that the cage becomes 1 flat piece. It's tiresome though and can cause alot trouble when 2 plates are supposed to have a connected detail. Simple tank treads for example, i can't get it to work.

Piflik
11-12-2009, 08:11 PM
Increase Rays by using SuperSampling (eg Scanline's Max 2.5 Star)

In Max' RTT Dialog's Projection Options you can turn off 'Use Cage'.

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