View Full Version : Saslite problem

12 December 2001, 01:45 PM

how do i fix it so the grass doesn`t grow thru the roots, any tips would be appretiated.

12 December 2001, 02:33 PM
If you have your ground geometry directly under the area the tree roots are, then you need to create your plane geometry with those areas removed so the grass doesn't grow up from underneath the roots and through them. Try a boolean subtract using the the tree trunk geometry to create the holes on the plane. I usually don't ever recommend any boolean operations as they provide unpredictable results but since it's just a ground plane covered with fur/grass it shouldn't be a big concern.

If you were using the full version of Sasquatch you could just apply an appropriate greyscale image map to define the areas of grass growth on the plane. A whole lot easier.

12 December 2001, 11:31 AM
well i tried the boolean u suggested but it doesn`t seem to have any affect i guess this is because the tree and ground are both nurbed objects with a low poly count. i guess the option is to manually add more polys to that area and tweak them to place under the roots then deleting them but this seems like a hard way to do it.
you don`t have any other tips on how to make the boolean substraction work ?

also do anyone know where i can find a good tut on the motion mixer ?

12 December 2001, 12:05 PM
Boolean operations work best if you're dealing with geometry that has enough detail to provide the required detail. Obviously if your ground plane is a single poly you aren't going to get the geometric result you need for your ground to have the grass grow outside the placement of the tree roots. So use a non nurbed ground plane with more poly count for your scene.

Take your models (tree roots and ground plane) and metaform them to make the models have more geometric detail than the nurb cages currently have. The metaformed tree roots will only be used as a tool for this operation. Once you have sufficient detail(poly count) then try the boolean operation. Once you get the "hole" in the ground plane that follows the contours of the roots, I'd use that high poly count ground plane instead of the "nurbed" version you were using earlier. You might have to tweak the boundary of the hole to match the fit of it against the outline of the "nurbed" version of your tree roots.

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