Speeding up sculpting

I need to do some hi-density mesh sculpting, but my machine cannot draw the results fast enough.

I use a laptop generally, because it has 3Gb of ram. However, I do have a desktop, which has less ram, ( 1.5Gb) but a faster processor.

My question is this: Where is the main bottleneck? Is a faster graphics card, ( neither is faster, but the desktop is at least upgradeable) going to solve the problem, or do I need a faster processor?

I don’t have the money to go out and buy an all singing all dancing new PC or laptop, so what is the best option?


I believe that memory is more important than processing power when dealing with dense meshes. Definitely it would seem that a faster graphics card would be a big factor too.

Have you tried the normal tricks to speed up sculpting? Backface culling (partial redraw) Starting multires with a nice base mesh (don’t start with a cube) Reducing the undo steps in user prefs, hiding parts of the mesh?

I have also heard that the recent Jwilkins builds can really speed things up as well.

I was told this in a sculptris thread, on how to speed up blender. It worked very well:

Thanks for those tips, they have helped, but they thing still runs like a sloth. Guess I’ll have to forgo any serious sculpting til I get a faster machine.

One thing that annoys me though is that, regardless of speed, and how you set the brushes, it is impossible to get a smooth flat-topped line from the draw tool. You can use the layer tool, but then if you draw over the line again, you don’t get one line on top of another.

Also, what does the ‘clay’ tool do? For me, it just makes the mesh leap about in weird ways, and then become covered in huge spikes!

Oh, and why can’t the thing remember the brush size and strength for each tool independently? I use a tablet, and the strength has to be set high to draw, but low for layer or smooth, so I spend half my life changing brush settings, rather than just switching tools, making a few strokes, and switching tools again.

I assume you’re using 2.5, because that’s where the clay brush is.
in the tool shelf, there’s a bunch of datablocks, named for the different brushes.
using those to switch tools, it will remember the settings. (as opposed the the buttons, which change the tool type for the datablock)
also, you probably know this, but you can use F and Shift-F to adjust size and strength.

as for speed,

  1. definitely turn off “double-sided”, it’s like the computer has half as many faces to draw :slight_smile:
  2. use the multires modifier, and start with a mesh of about 1,000 polys.
  3. don’t worry about VBOs, it’s already turned on, and it’s handled automatically in sculpt mode.

more RAM, definitely upgrade to either your machine’s max, (probably 4GB) or your budget’s.
look into getting a GeForce 2xx graphics card. you would not believe how big a difference a $50 graphics card can make.

I also found that sculpt in 2.5, at least the standard one from blender.org would sometimes not even drag, depending on which brush was being used. Problem was fixed by using my own “build” via the scons thingamie for my Ubuntu system.

Compiling your own build is actually fairly straight forward if you follow the steps from here: http://wiki.blender.org/index.php/Dev:2.5/Doc/Building_Blender