Ok, a while back there was a thread at odforce about possibly sculpting a model and exporting that sculpt as a displacement map to be put back on the clean model (thus getting rid of processing the sculpt of a high poly..)

Talkien figured out a way to get the sculpted information in to a b-w (0-1) coloring on the model. There is example files on the thread at odforce. But nothing was figured out about how to get that grayscale color information unwrapped to a 2d image to be put back on the model.

I think this could be really useful if it could be done, so I am trying to reopen it both here and over there to see if any new ideas may come of it.

Thanks everyone,

Dave

http://odforce.net/forum/index.php?s=483da3b5274681e76d39bde71e26648f&act=ST&f=15&t=1531&st=0&#entry10555 [odforce.net]

I know there's a way to do this in Houdini, but the solution will have to wait till later today unless someone beats me to it. I need to sleep.

For now, check out ATI's standalone normal mapper utility. It'll generate the maps you need based on high and low versions of a model.

http://www.ati.com/developer/tools.html [ati.com]

Not sure but it may even run under Wine if you aren't on Windows.

Well, I have a solution for you, if this link works then you should be able to get an example hip file.

http://www.fourthwall.ndo.co.uk/hips/DisplaceMap1000.hipnc [fourthwall.ndo.co.uk]

Open it up and look in the model object, I've used a low res sphere and a high res sculpted one. At the bottom of the network should be a render op for generating the map. Run this first and then check it worked by looking in the cop2net, (everything is set up to render out to $HIP).

You should then be able to render the low res sphere using mantra1 and it should (fingers crossed look like you rendered the high res sphere)

I'll try and put it all in a HDA so it's a bit easier if I get time :wink:



Si

Ok…… that was very kool. :shock:

In order for this to work, does the displacement map have to be based off a subdivided version of the object?

or

Can you feed any geometry to it?

ie. make the sphere displace into a box sop?(or vice versa… )

You can base it on anything, I just used subdivision for speed. The only thing you need to watch out for is that your lo res geometry is completely inside the high res one, and that it can be “hit” by rays sent along the normals of the lo res geometry.
Also, is you displace the surface too far you will need to up the displacement bounds for the object otherwise it will tear apart.

Si

no comprende… :?

“lo res geometry is completely inside the high res one, and that it can be ”hit“ by rays sent along the normals of the lo res geometry. ”

Well….. :? the lo res sphere needs to be inside the hi res sculpted version, so that none of the lo res one pokes through.

Also, if you have undercuts in your sculpted hi res geometry the lo res one can't necessarily “see” it all.

Basically it works the same as the ray sop, it just does it as a render. So if you ray your lo res geometry onto your hi res one and some of it misses that's exactly what will happen when you try and render a displacement map from it.

Also, the way I haven't it at the moment the hi res object can only be displaced by a maximum of 1 unit along the normal of the lo res object. This is easy enough to change I just haven't done it yet.

Si

i just found this and its something i want to look at… byut the link is now broken, does anyone have that example file?

ta,

Mark

Here try this, hope it still works, I haven't tried it.