Zbrush, Major Performance Issues?

Nronjon

Hey guys, 

Firstly, I apologize if this is in the wrong place - it seemed like a pretty technical question.

I was hoping I could get some thoughts on my computers performance issues in zbrush. I've been pulling my hair out trying to sort it so thought I'd turn to the community! 

I've been suffering from quite bad lag when navigating around the mesh while zoomed in. So much so that it's really hindering my personal sculpts.

The lag becomes almost unbearable when working on a subtool at around 200k. The whole ztool is roughly 1.1 million points, comprised of 5 to 6 subtools. While working, every subtool  is at the lowest subdivision, and every subtool apart from the one being worked on has its visibility off. Simply rotating the subtool makes the CPU usage shoot to 100%

Essentially, there is nothing to justify this lag, in my opinion. 

 My personal Computer Specs are:

 - AMD Phenom II 955 quad core 3.2ghz 
 - 16gb ram
 - AMD Radeon HD 7900 series 3GB VRAM
- Toshiba h200 SSHD 1TB (600GB free)


Below are some things  I've already tried/checked but to no avail. 

•  Dynamic subdiv is turned off on all subtools

•  Compact mem set to 4k

•  multithreading already optimized, no further improvements

•  Mesh is subdivided clean-ish topology, no dynamesh.

•  Document res is around 2k by 1k, lowering this helps but not significantly, and it has to be reduced to under 1k to notice anything, which isn't really a workable size.

• initialized zbrush and removed any custom UI as I heard previous versions caused lag.

• Running 64 bit, same issue in 32 bit.

• Reinstalled zbrush multiple times.

• Same issue with any ztools, not just the current one.

• Changed scratch disk directory to a secondary hard drive

• Installed Zbrush to a secondary HDD ( 7200 RPM 320GB )

My computer generally runs quite well, working fine with photoshop, substance painter and a range of recent games such as the witcher 3 on pretty high settings.

Currently I'm a little conflicted - I'm tempted to either get a new processor or SSD in hopes that one or the other would solve this issue. However at the same time I feel that my current specs should be sufficient and I am hesitant to waste money.

Any thoughts you guys might have would be brilliant, as I'm at my wits end on this one. 

pior

That's the irony of Zbrush performance - a computer running all recent games and 3D apps flawlessly can still struggle with Zbrush because its bottleneck is the CPU. Meaning that a recent, medium performance Dell with nothing special to it may still run Zbrush better than a gaming PC carefully upgraded over the years but still using a reliable but old CPU/MB.

The one thing you can try is to enable the "Quick and Dirty Edit" option in ZB in the Performance tab, as it more or less doubles the viewport performance with no side effects that I know of. You can also take the habit of disabling shadows, as that speeds things up too.

Also, keep in mind that a lot of Zbrush users are okay with poor viewport performance - meaning that for some, the performance drops you are reporting may be seen as "normal".

Lastly, you can also tackle the issue the other way around by always keeping your sculpts as lowres as possible. Not only will you (obviously) get better performance, but you will also be able to get your models out of Zbrush more easily.

Nronjon

Thank you for the response, I appreciate it!

Quick and Dirty edit is already enabled, and disabling shadows does offer a slight improvement in performance but nothing too noticeable.

I appreciate that performance drops in the viewport may  be considered normal, however this is happening at such a low polycount. I've worked as a Character artist for 3 years and I am often reaching a position where I have 5 or 6 subtools, each with roughly 2-3 million points each. Therefore a ztool with between 15-20 million active points, and even at this point I don't experience the same lag as with this situation. However the office computer does have a better CPU, even if every other component isn't as strong. 

I understand and agree about keeping sculpts lowres and the sculpt itself at its lowest subdivision is less than 5,000 quads. The problem is, I am hanging around in the 'blocking out' stage because my computer doesn't have the ability to zoom in and work in detail. Effectively, I need to work at a higher subdivision in order to progress my sculpt. 

Perhaps I am a bit of a zbrush snob haha, but I'm used to a certain level of performance when working on my sculpts and this lag I'm experiencing at such a low polycount is painful.

My office computer runs an intel i7, 4 ghz - I appreciate that it is a newer processor, and is more powerful....and also has hyperthreading.... but does it really leave my little old Phenom II in the dust to such an extent? 

If the CPU is the bottleneck then I will have to upgrade it to something newer, but still within my budget.

pior

The model/tool in question is probably corrupt in a unique, Zbrush-specific kind of way. Export as OBJ, re-import, and reconstruct subdivs.

Nronjon

I thought it may be a case of a corrupt ztool, so I tried with multiple different ztools and all of them react similarly. Therefore unfortunately i'm not convinced that will solve the issue, however I will look into it next time i'm at my computer. 

Looks like I may be forking out for a newer processor. 

Thanks for taking the time out to reply, i appreciate it. 

kanga

pior said:

The model/tool in question is probably corrupt in a unique, Zbrush-specific kind of way. Export as OBJ, re-import, and reconstruct subdivs.

Yep. If you are experiencing this a one time problem the only place to go is to assume that there is something up with the model. I'd do what pior says. Export your subtools as .obj one by one (at the lowest level), and mesh check them in a standard 3d app. Something like xview in Max. Once they are clean GoZ them back to ZB, reproject them over the problem meshes and once you have a good copy delete the problem meshes. This sounds like a mesh problem because as you said, normally you can work without any difficulty at your current polycount.