Well, Steam coming to the Mac platform is great news. Unfortunately, it's not without its bumps and bruises. Read on for my mini-review.
When Portal originally came out, I had the same computer I have now: an Apple Macbook Pro SR 2.2Ghz with 4gigs of ram and 128mb nVidia 8600 GS video card. I played the game on medium settings on a 1280x1024 external monitor while using Bootcamp and Windows XP. The game ran pretty silky. I never checked for frame rates but I remember the experience being pretty pleasant.
So when Portal was released for free on the new Steam for Mac platform, I had to try it out. I'm much too lazy to restart into Windows all the time just to play games! Surely, this is a godsend.
Well, not so fast. First thing's first: playing games on Windows means using DirectX, a proven and reliable gaming platform. Love it or hate it, it works pretty well. To run on a Mac, a game written in DirectX has to be re-written into OpenGL, an open-source gaming platform (also used on Linux). My experiences with OpenGL games is limited, but when comparing DirectX games to OpenGL games, OpenGL has always been the loser. I don't know any of the technical specifications, but just through my own personal experience (even when playing older OpenGL games on my old PC), OpenGL performs worse.
So the new Portal for Mac is written in OpenGL. And I've come to find
the same problems I usually do with OpenGL games. On the Mac side, I was running everything on the lowest settings at a lower resolution (1024x768). Any time an open portal is visible in my character's view, the game slows to a chug. Not just portals, but it seems any particles or special effects just kill the system performance, even on low settings. I wouldn't say the game is unplayable, but it's definitely several steps down from what I experienced a few years ago. And this is the exact same computer!
One of the coolest effects in Portal is firing your portal gun, and being able to see through your fired portal the area you are about to enter into. Sometimes it's recursive and you can see yourself! Unfortunately, with the current graphics settings, all my portals are black in the center, showing nothing through them. This not only makes some parts of the game more difficult, it's a hugely disappointing pitfall in what was once a sweet graphical effect.
Keep in mind this was with a 128mb Laptop video card. Those of you with more video memory may have better experiences, but I can't say for sure. OpenGL shares a lot of the blame for poor performance, but maybe it's just a video RAM hog. I don't know. My MBP is definitely bottom-of-the-barrel for running Steam games on Mac (I don't believe integrated Intel graphics even works with Steam), but I still can't help but be disappointed. Maybe this is something that can be fixed with updates to Portal's game code, maybe not. All I know is that I'm not ready to give up Bootcamp yet.