I am having a problem with my undo (Ctrl-z and the button). All of a sudden it stops working and I’m stuck with a maximum of 4 undos on the particular Tool that I’m working on (and all its subtools) even if I save it then reload it. If I switch Tools, say load a sphere 3d and convert it to a polymesh, I still only get 4 undos max. If I Initialize ZBrush, and load a sphere 3d, convert to polymesh, then I can go over the 4 undos and it works properly. I have the [EDIT:UNDO,634][EDIT:TOOL:UNDO,634] in the StartupHotKeys.txt file but that doesn’t solve the problem. I run into this on almost everything I work on. Undos work fine for a while then stop working and I can’t figure out what I do to make it stop working. Has anybody else run into this that can tell me what i’m doing wrong.
What I have noticed is that it is an intermittent thing and that it is fixed by rebooting my computer.
Sounds like a memory limit.
The larger the file size, density of tools, how many tools you’ve loaded, other programs you have open, etc. all take system memory. Eventually it all builds up and your limited to how many undos can be kept.
It can also make actions take much longer and cause Zbrush and your system to become unstable.
I think it’s normal but if you think it’s beyond what would normally be expected you can watch how your system is using memory in different apps and/or while using ZB. You can also run a ram test if you think it’s necessary.
I usually do a periodic save and reboot if it seems to be lugging too much. (You can never save too often!)
Good luck,
Sam
Thanks for replying Sammer1!
This is occurring on relatively small file size. eg: 1 tool with 6 subtools and only 1.8 mil. polys total. I don’t have any problem with ZBrush bogging down, in fact it runs quite well and stable on my 32 bit OS with 2 Gigs of Ram and I generally only run 1 app at a time.
I did catch it screwing up though, and it was right after I applied a cavity mask, then inverted it and did a bit of polypainting. I did maybe about 10 strokes with rgb only, changed my mind about what I did and started to Ctrl z but I could only do it 4 times and it stopped. When I opened the edit menu, it was stuck on 4 undos and that’s as far as it went. I tried to recreate the problem after I rebooted, but it wouldn’t do it the second time.
I don’t have any problems with any other apps.
As far as my Ram goes, I can run Memtest86 for 8 hours without any errors so I don’t think it’s that.
I am glad that none of my Zbrush files are screwed up though and I do incremental file saves just in case. If it’s only an occasional problem and a reboot will fix it then I can live with that I guess.
Nobody else is having this problem?
I know it’s not my computer because I don’t have this problem in 3.5R3.
It just does this whenever it feels like it. I can go for 10 minutes with no problems, then it screws up. I can go for 1 minute and it screws up, and for the rest of the session, no matter what I do, I only get 4 undos.
I don’t really feel like re-installing until I can get some comments on this, because if I re-install and it’s still doing the same thing…well…that will really PMO.
ZBrush has a unique undo system. The number of undos is set by the Preferences>Mem>Tool Undo slider. By default, this is set at 4. This tells ZBrush to never make fewer than that number of undos available to you. However, ZBrush will always try to keep more undos available and will only start sacrificing them if the memory is needed for other things.
This is why you start out with more but as you work you drop down to four, but no lower than four.
Yes, you CAN increase the value of the slider. This doesn’t mean that you should, however. Every undo is essentially a copy of your model. Even a model with only 1 million polygons would turn into 64 million if you maxed the slider setting – pushing things to a point where your computer would scream “uncle!” Don’t increase the Undo slider except in a case where you desperately need the extra undos, and then only do so for the time that you need them. Return to 4 as soon as possible – certainly before you save, since saving is a memory-intensive operation.
zber2, in your case you have a very weak system. 2 GB of RAM is not a lot. Your operating system uses 1 GB, so that leaves only 1 GB for ZBrush. With that low amount of RAM you’re going to be pushing things even at about 4 million polygons. You’ve stated that your model is 1.8 million polys. Four undo levels is over 7 million polygons in memory. You really shouldn’t be surprised that you’re quickly being limited to four undos.
Thanks for explaining that aurick. Makes sense now. I did have 4 Gigs of ram a while back but 1 stick died. I will be getting another 2 Gigs soon and see if that helps, but like I said, it wasn’t doing it in 3.5R3 and I was testing it on the same model.
Picked up 4Gb Patriot Viper II DDR2 1066Mhz RAM today and installed it. You were absolutely right aurick, that’s exactly what the problem was and thanks again for explaining how ZBrush handles undos. Problem solved. 
