EDIT 12-19-11: SAI 4 Mac 0.3, download link updated.
New version has a completely different Wine core for testing.
If you're having trouble launching it install XQuartz.
This is PaintTool SAI running on Mac OS X via a self contained Wine wrapper. I put this together and figured it'd be useful for some people here on dA. If you'd like to give it a try click the download link. Enjoy!
To install: Double click to unzip and drag PaintTool SAI4MAC.app to your Applications folder.
Known issues include no tablet pressure recognition, this is a limitation of Wine and X11, sorry.
Repeat: TABLET PRESSURE DOES NOT WORK AND WILL NEVER WORK.
Maximize may not always function but you can still drag the window to the desired size.
DISCLAIMER: If it's apparent that you didn't read the description before making a comment don't be surprised if your question goes unanswered.
Attention: Due to the massive influx of stupid comments from people that didn't read the description or bother to comprehend anything about this before commenting, I'll be taking this down by the years end as I'm tired of constantly having to respond to these people. I decided to leave this up since stupid comments en masse seemed to decline, enjoy.
I likely won't be making any new updates for future versions of OS X or bugfix releases, this may change but the future prospects aren't likely, current version works on Mountain Lion but you may need to get the XQuartz libraries installed.
does anyone know why the pen pressure doesn't work? I have the full version on my windows laptop but I want it on my mac as well for course work. It's sort of necessary that I have working pen pressure for a lot of my stylised drawings. Is it possible that those having this problem have not changed the pressure in the brush settings? (The scroller under the pen size)
Yeh I saw that they mentioned it didn't work, twice. c: Thanks for the slightly condescending reply though, super helpful Don't go all sassy pants on me cause you were the one showing unnecessary hostility towards someone just looking for a bit of information as a new mac user. I'm not rude I promise.
If you don't understand how wine bottling works, (basically taking a windows based program and forcing it to work on the mac OS via some fancy programming) that's entirely different than ignoring the warning on the description. Your original comment made it sound like you had just not bothered to read the description; and they are wanting to take this down thanks to people constantly doing just that.
With so few options for decent art programs on macs that don't cost an arm and a leg, it is extremely helpful to have this kept up as I believe Gimp and FireAlpaca are the only others that work with psds and are free... but they aren't really great since they don't handle PSDs made in Sai or Photoshop well at all.
I think having Photoshop would be easier for mac users, and even though I have that on my mac (totally through super legal internet file sharing //nervous laugh) I mainly like sai for the easy brush settings and stability control for using tablets. It's such a bother to not be able to get pen pressure since it is a big part of most digital art, with style, digital paintings, and fine detail. :c