CrossOver Support - Community Forums

I have steam, and the Orange box installed with crossover games. Everything works fine save for portal, my problem there is the portal animation. When I make a portal rather then being a view out of the other portal it is just the wall or floor with a blue or orange oval line circling. Occasionally it projects real portals, but only for a few seconds, and rarely, how can I fix this? (Also other then that issue I can put it up to highest detail, or lowest without flaw.)
Stats: MacbookPro 13', Nvida 9400M, 4 GB 1067 MHZ DDR, Leopard 10.5.8, Intel 2.53 GHZ processor.

This is a known bug, but unfortunately its a fault in the OSX graphics driver.

Portal masks the area where the portal content is drawn in the stencil buffer, and when it draws the portal content it sets up the stencil test to draw only to those marked areas(otherwise the portal content would overdraw big parts of the wall). For some reason writing to the stencil buffer fails sometimes, and sometimes it works. We've compared the opengl state between working and failing draws, and there's no difference, so we have little to no chance to work around this issue. (At least we haven't found a way yet, otherwise it would be in cxgames 8)

A workaround is to switch the game to dxlevel 81. This changes the way Portal draws the Portals a bit, so it doesn't hit the driver bug.

How might I do this, I am somewhat new to Mac.

Switching the dxlevel doesn't have anything to do with running on a Mac, its a game setting. Right click on the game in Steam, click "Properties". On the dialog that comes up there's a button "Command line arguments". Add "-dxlevel 81" there (make sure to keep a space before the -, start the game. Then, exit the game, and remove the -dxlevel 81 again - the game has it stored. Then, start the game again, and see if the portals work better.

You can change the 'portal render depth' in the game's options. I had that problem and noticed it was set to 0. I changed it to 9 and that fixed the issue. Hope that helps.

Thank you very much adding -dxlevel 81 fixed everything.