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rustbucket
04-24-2006, 03:33 AM
Im having a hell of time figuring out whats going on with my PM deformations. Im using the PM (with texture turned off, normalized and deformation turned on). Im using an alpha to displace my geometry a bit. Everything looks peachy when I drop the alpha onto the canvas in PM, however, when I pick it up with PM everything becomes aliased and muddy. Im thinking its not my model since im at 2 million polygons. Can anyone shed some light on the issue? Im just trying to preserve the detail of the alpha on my model (Happens with both 8bit and 16bit, so im thinking its a setting im missing)?.

Thanks in advance.

rustbucket
04-25-2006, 01:14 AM
Bump.

Guess this isnt a common problem.

Mr Moose
04-25-2006, 12:28 PM
Without being able to see a pic first hand, it sounds like you need more polygons. 2 milliion polys sounds alot... but how big is your model - or put another way, how close in to it are you when you try to add detail.

When sculpting detail in PM you're not working with actual polygons, which is why everything looks fine. When you Pick-up your work from the canvas when you leave PM, it is converted over to polygons. If there is not enough polygonal detail for your PM work to reside on, you will get the results you are seeing. ZB can only work with the polygons with which it is given.

Also be sure that in PM you only paint/sculpt on the surfaces which are perpendicular to the projection, otherwise you will get streaking.

Sorry if you're aware of all this already, but this comes up quite often so is a safe bet to assume it's the problem you're encountering here.

Have you considered using the BumpViewerMaterial.zmt to create a bump map for the fine detail, reserving displacement for everything else? It's quite common to do this. At the end of the day, it's unlikely that anyone will be able to notice the difference.

:)

watteville
04-25-2006, 12:58 PM
i agree totally with mr. moose and especially when it comes to the point that the deformation you're applying have to be perfectly perpendicular, that means they have to be facing you. otherwise you get irregular deformations.

rustbucket
04-25-2006, 06:14 PM
Thanks for the reply guys, ill give that a whirl tonight.

eblondin
04-25-2006, 07:51 PM
I ran into a similar issue and in my case I ran out of polys so I did all my high frequency detail in a bump map which is normal workflow for really high frequency detail like wrinkles.

Any how when I used projection master and used an alpha like you, it looked well in PM but when I picked it up, it looked horrible.

The problem for me was my uv layout, GUV and AUV tiles by default didnít assign enough uv space to that portion of my mesh due to not having a uniform consistency of polys around my mesh.

at first I was using default AUV tiles which by default creates a bad uv layout for my mesh, I switched to GUV that was even worse so i messed with the ratio slider on AUV and got pretty decent results because that slider changes the ratio of each uv shell so you get a better consistency of large uv shells to large geometry faces on your mesh. But that created bad seams.

So it wasnít until I unwrapped it by hand that I got a much better proportion of uv space to geometry space ratio. And got the best result in the end.


Here (http://www.zbrushcentral.com/zbc/showthread.php?t=31456) is a link to the thread with pictures detailing what i am talking about

hope that helps

ryankingslien
04-26-2006, 01:42 AM
can u post images? That will help. :)


r

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