ZBrushCentral

Displacement maps and hard edges

ZBrush Usage Questions
#1

Good afternoon all. I am attempting to use Zbrush to add detail to models that have very hard edges. Let us take a box as an example.

3DMax 8: Create box. Subdivide box to get some base subdivision, looking for evently sized quads. UV Map the box (now a polymesh), no overlapping UVs. Collapse Stack. Select all lines and crease to 1.0, thus making them 'hard' edges. Subdivide box using 3 iterations and nurb subdivison. Export box as an object at this higher nurb subdivision. Save file. Open Zbrush Import box. Edit mode Go to Geometry and reconstruct subdivison 3 times until we get a box that matches our original polymesh box in max. Set morph target. Go to highest subdivison. Sculpt. As an example I dropped to canvas and added an arrow alpha on top of the box, 25 or so intensity. Pickup box, arrow looks good. Go to lowest subdivision, morph to low res box. Using settings in the Max-Zbrush tutorial export displacement map. Now looking at the displacement map:

Everything looks ok except for the fact that the edges all have a white painted edge, as if Zbrush is still trying to round off/displace the edges of my mesh when it exports.

Any ideas? ~ JamesCG

Attachments

WhiteEdges.jpg.jpg

box.jpg

#2

If I displace a box that is subdivided in zbrush using the smt (subdivide smooth modifier) I get a good displacement map. If I subdivide the mesh with smt off, I get an odd displacement map with displaced edges appearing thoughout. Any ideas about how to fix this?

~ JamesCG

#3

When it comes to generating the displacement map Zbrush is assuming that I will be subdividing my box before I apply a displacement map. Thus the edges of my UV layout have a white edge. Zbrush’s exporter is thinking the displacement map will have to “push” the edges out to form a hard edge because the box will be subdivided and rounded when it starts. I need a way to export a displacement map with an object that was subdivded with SMT off and will be applied to an object in MAX that is 1)not subdivided or 2) subdivided with creased/hard edges.

Hmmm… I may have to start looking harder at the displacement generating side of Zbrush.

~ JamesCG