ZBrushCentral

UV's stretching??

ZBrush Usage Questions
#1

I noticed that if I bring in a simple cylinder and add detail in various places like at the ends and the middle, when I create a normal Map it gets very distorted, it seems to pinch the ends and stretch the middle, I have tried using the smooth UV, create a normal map off the original blend shape, or with the modified level 1 mesh and its always the same results. Here is an example notice how the rivets are stretched in the middle and compressed at the end, and compressed on the lump in middle as well.

NormalMapStretching.jpg

#2

For some reason, your UV coordinates got stretched I think. You will need to stretch out the UV’s in the ‘U’ up and down dimension within a UV editing program outside of Zbrush.

#3

this is all done in Z brush, and I havnt modified the UV’s in any manner, this is happening when you switch back down to the low res mesh and generate a normal map.

#4

Off hand, I can spot one big difference between the ZBrush model and the model with the map applied – one is subdivided/smoothed and the other is not.

Does the map look good if you turn off Quick 3D Edit and set Tool>Display Properties>DSmooth to 1? If so, then there’s your answer.

If you want the difference map to be generated for the smoothed model, then the model that it’s applied to must also be smoothed. If the model won’t be smoothed, then you need to turn off Tool>Geometry>Smt before you click the Divide button. This will add the extra polygons that you need for working with Projection Master, but won’t smooth the mesh. The end result will be that your normal map will be created for the unsmoothed mesh rather than the smoothed one.