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I'm suprised it doesnt work, cause the origional Halo was built around the nVidia card (GeForce3 Ti, i think).

Some GF3 proto cards were used in development, and the PC version can detect and note their use. The shipping Xbox uses a proprietary chip, the NV2A, which is basically an upclocked GF3 (roughly halfway between the original and the later GF3 Ti500) with the second vertex shader unit of the GF4, allowing twice the geometry processing per clock. 

I would have thought that [the?] code would have remained intact.

It's a matter of APIs. As one of the IMG Forum threads with the programmers points out, OpenGL was later than DirectX to the programmable shader show, and support for the latest, version 2.0 shaders under OpenGL (for Mac currently, at least) leaves only the ARB path, not currently working under Mac OGL and/or nVidia drivers for same... even on PC, it's taken until just recently for nVidia to release drivers that allow their FX line, powerful and elegant in architecture but apparently difficult to program PS 2.0s for, to regain competitiveness with ATi, despite higher clock speeds. It's partly a matter of esoterica like code ordering and scheduling; nVidia had to make their own compiler to get the speed, where ATi's current arch works fine with MS' regular DirectX compiler.

In short, NV's FXs are a pain to code high-level shaders for, and it seems it takes a Carmack, writing separate code paths for NV10, -20 and -30 (GF1/2, 3/4, and FX), as well as generic ARB and ARB2 paths, to combine good speed with Doom III's visuals for NV and ATi- and, of course, DIII isn't finished yet, tho the renderer is said to be. With apparent simultaneous Mac dev, it's all still a bit of a mystery. Game engines do differ.

Wow.  It's nice to have someone that knows their stuff.  That took me a good three reads before I was sure I understood what you were talking about. 

Scooter"]

I imagine a large portion of [MA] won't be playing Halo due to hardware issues.

Same story for UT2003... but that game sucks anyway, so nobody cares

hey dont be dissin ut2003...ass.

Hey now.  Take it easy on my eawypoo.  He's a cool guy.

Wasn't Halo rewritten to support Direct X alone, when MS bought Bungie? (Sorry if this has been said already).

If so, then the PC port would have gone quite smooth, but the Mac port should have had a complete change, from DX to Open GL.

The PC port was anything but trivial, altho the biggest deal was rewriting the network code, they say. Even so (and pulling in a paragraph from my first post, a whole page ago for the forgetful... )

The Xbox and a PC are not as identical as some would have you believe. There are differences between the platforms in DirectX, and the unified memory architecture of the Xbox can make programming for it quite a bit different than for a PC. Thus, Gearbox actually had a lot more to do in porting Halo than simply allowing the game to run at any resolution and tossing in mouse and keyboard support. Most of the game's shader effects have been rewritten, utilizing a variety of code paths to support everything from fixed-function graphics pipelines to the latest 2.0 shaders in DX9. This makes it an interesting graphics test, if only because there are so few games that utilize 2.0 shaders at all. In the 2.0 shader path, Halo does utilize partial-precision hints, allowing GeForce FX cards to operate using faster 16-bit floating point operations.

XBox has only 64MB RAM total, shared between video and other game data (Unified Memory Architecture), but since it's unified, it has enormous internal bandwidth, the data paths between chips being very wide. That alone makes game code different than for PC, and partly explains why bandwidth is cited as crucial by Westlake's DJ- things like AGP 8x and PCI-X can make a serious difference if the machine's other parts, e.g. videocard are fast enough to take advantage... neither Macs nor PCs, obviously, have a UMA, but many times the RAM; hence the need to be able to move data fast for code originally written for that other architecture. Despite the PPC/x86 difference, Macs and PCs more resemble each other in hardware and architecture (separate CPU, videocard, RAM, HD linked by similar PCI and AGP buses) than PCs and Xbox, which have similar parts but dissimilar arch.

The game engine was rewritten to take advantage of a fixed (but somewhat nebulous during development) hardware target- the most capable videochip then extant, a fairly fast CPU with SIMDset (SSE), and that UMA. With Halo being a- really the- launch title for Xbox, and dev time short for such fundamental rewriting, I'm guessing code portability was something that had to be sacrificed. Bungie could still rest assured that future hardware would eventually power thru any code inelegance. (Bugs are a different matter; in The Library, on PC I've seen 2 swapped weapons fall into the same "hole" in a wall, there to rotate with a terrible grinding sound...a different kind of enemy... )

The PC version has a greater commonality (with Xbox) thru DirectX, but many more pieces of hardware to support (or not; you should see the hundreds of videochips/ cards it tests for, to accept or reject as unsupported- anything but a fixed hardware target); the Mac port obviously is simpler there, but has to contend with conversion to a different video API with recent, even new OS extensions to support the even more advanced shaders written to better the original's graphics (little wonder that OS10.2.6 [?] is spec'ed as minimum, with 10.3 highly recommended), in addition to the usual Mac/DX issues (Directsound 3D, EAX, Dolby 5.1 if possible; controllers etc).

Wow. It's nice to have someone that knows their stuff. That took me a good three reads before I was sure I understood what you were talking about. 

I didn't even have time to get into the full/partial precision difference between nVidia (16/32 bit) and ATi (24/24 bit)(In the 2.0 shader path, Halo does utilize partial-precision hints, allowing GeForce FX cards to operate using faster 16-bit floating point operations)...

...but thanks anyway. 

Scooter"]

I imagine a large portion of [MA] won't be playing Halo due to hardware issues.

Same story for UT2003... but that game sucks anyway, so nobody cares

hey dont be dissin ut2003...ass.

UT2003 is a big piece of ass. I find the original much better, somehow 2k3 killed a lot of the fun. But Halo pwnz joo, so STFU.

Scooter"]

I imagine a large portion of [MA] won't be playing Halo due to hardware issues.

Same story for UT2003... but that game sucks anyway, so nobody cares

hey dont be dissin ut2003...ass.

Hey now.  Take it easy on my eawypoo.  He's a cool guy.

Pffffft! Not! I'm with Scoot! hehehe

Now Bat...Bat has his hooks in deep.

Arg, Halo is just over a week away.
Its killing me.

So, uh...
I gather from other threads that it's gone Gold Master.
Get those credit cards ready!

According to MacSoft, the game will begin shipping from Destineer's warehouse on Thursday, December 11. Halo for Macintosh should be available in stores in the week of December 14 and in Europe later the same week.

http://www.insidemacgames.com/news/story.php?ID=8825

lol ut03 sucks and halo sucks.


lol i thought halo would out for the mac by now 

Uhhhh... That's why you pre-order online... cuts the wait time by a few days. You pay shipping, but what's a few bucks to a rabid Mac-gamer. Muhahahahahhahaha...

Anybody in Minneapolis, Minnesota? Wish I was.