ZBrush Bug Notice

To those of you who haven't already discovered these lovely nuggets, Z 3.5 has some secrets awaiting when it comes to the use of Decimation Master, Print Exporter, and appending subtools. At the root of the problem is a bug that is running throughout that will randomly change the scale factor and XYZ offsets of seemingly random subtools. The subtools will appear to all be in scale to each other, but upon export, the nasty truth is uncovered. If you were to then import these models into another piece of software, you'll discover that some parts have changed scale and relative XYZ position. You may experience this problem after using Decimation Master on a part (main culprit) or you may find this happening after appending subtools from another ZTL. There is no knowledge of how to definitively fix this bug. Here's what you can do:

-On you Tool menu, select each subtool and check the Scale and XYZ Offset values under "Export". If the scale is not 0 or 1, and the XYZ offsets are not 0, you should reset them before you export your parts.
-You may perform what was mentioned above, only to find out that some parts read correctly in "Export", but are still off. I have found that in my ZTLs that have this problem, even though some read correctly but aren't, they are still off by the same values as the ones that do show the discrepancy in your "Export" values. You need to find out what the scaling factor should be in order to get it to the right size. In my case, the parts that were off and the values showed this were:

Scale: 118.5709
X Offset: .170627
Y Offset: -.293222
Z Offset: -.196549

The parts where this was the case, I reset the values and everything was fine. However, I needed to find a scaling factor to accomodate for the parts that were *still* off, but read correctly. To find the Scale factor, you divide the target value by reality. In this case, I divided 1 by 118.5709 and got .008438256014999. Z only carries out to the 6th decimal point, but that is plenty efficient to get it to export at the correct size. Other software packages carry the values out further, so truncate to your specific need. So you apply that .0084xxxx value to the Scale under the Export menu, so that now the part will export correctly. Now you have to worry about the relative XYZ position being off. To remedy this, just invert the values of the offsets listed above (even though they currently read 0) and the part will return to its correct position upon export. The weird thing in all of this is that you should see NO changes in scale or positioning of your part on screen.

Some people have no problems like this, but a fair number do, and there's no known fix for it at the moment. I'll continue to update this post as more information is discovered or unique situations encountered. Until then, CHECK THOSE VALUES!!!