Hi,
I’m a relatively new user of Zbrush, but have been using it for a while. I’ve just recently downloaded the Decimation Master plugin and used it on a 10 million poly model. Got it down to 700k, but the viewport seems to lag when rotating or scaling. The viewport does not lag when i’m rotating or scaling the 10 million poly model though…
Am I doing something wrong?
Nope. You’re doing it right.
The difference is that there is something called the QtransThreashHold. (preferences>draw i believe) It basically looks at a mesh you have and when you rotate at a subD level over a certain number (40k default I think) it displays a subD level under that number to help performance when rotating. Rotating your mesh takes processor power, not RAM.
Anyway, when you decimate the model you remove all of the subD levels so it doesn’t have a lower version to look at when you rotate.
If you take your 10million polygon mesh and lower it’s subD level to around 700k, then hide a small part of the mesh…1 polygon will work. And then rotate the mesh you should see the same slowdown. When a part of the mesh is hidden the Qtrans doesn’t take effect. The reason for this is so you can zoom in on an area like the nose or cheek bones and only that and still rotate the mesh to check for highlight changes and the form of the mesh.
Anyway…that explains that.
Ok,
Thanks for the information, greatly appreciated!
goast666 provided the good answer 
hello so is there a solution to spped up the viewport navigation after using decimation master?