[Platform Differences]

Do you have any examples of this? I wouldnt expect this to be the case.

-Dan

Like screenshots? I don't think that would speak that well for the look and the feeling of how they are rendered differently. As of now, I can only show you mac and windows screenshots, because I don't have graphics drivers for my FBSD partition.

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Original post by BSD Like screenshots? I don't think that would speak that well for the look and the feeling of how they are rendered differently. As of now, I can only show you mac and windows screenshots, because I don't have graphics drivers for my FBSD partition.

If you can't tell the difference by looking at screenshots of each, then how can you tell the difference? Is it the performance?

I'm sure you can tell the difference with screenshots, so I'll go get some in a few minutes. I meant that its more than just what the screenshot would explain. The game feels different because of the way the graphics are rendered differently (if graphics rendering is the reason for platforms looking different).

One thing I noticed is that sometimes, input events seem to be handeled a bit differently which can cause quite a difference in feel (especially in fps games), never seen any graphical differences though (os to os, rendering can look slightly different with different graphics cards)

I don't know what to say... I know its not a difference in hardware. I e-mailed activision and they gave me some horrible answers, such as "If
programming for each operating system was the same software would work cross
platform." Thats after a couple e-mails, after the first e-mail they said something like, you can run windows games on a mac. I don't think hiring illiterates for costomer support is a good strategy.

Here is a little graphic differential description between the OSes:
The graphics in linux seem to be more smoothed down, on mac os x more detailed (and most diverse feel among the OSes), and in windows seems to have the cheapest look (it seems more directx-ish, seemingly a flatter geometry).

I was going to post screenshots of mac os x and windows, but when I take screenshots in mac os x they come out garbled. I don't know if you can attach images in this forum anyway.

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Original post by BSD Here is a little graphic differential description between the OSes: The graphics in linux seem to be more smoothed down, on mac os x more detailed (and most diverse feel among the OSes), and in windows seems to have the cheapest look (it seems more directx-ish, seemingly a flatter geometry).

You know what, i always experienced this when playing HalfLife in D3D and OpenGL. In D3D the the textures/fonts always seemed washed out and blurred whereas they looked crisp and sharp in OpenGL. I know now that this is because of the way the graphics code was coded and not because of the API, but back then i didnt do any programming so i used to think OpenGL was superior in image quality and chose OpenGL over D3D when i started programming.

I can confirm BSD findings. I had a Mac and am getting another one soon. I played Q3 on the Mac and it did look better. One thing is the level where you fight sarge the archway where the plasma machine??? is at their is an archway into the room. If you are on mac that archway is smooth and round as can be when you are underneath it and looking up at it. On PC same situation the archway isn't smooth or round its square. They are cutting corners to get better fps at the cost of image quality. I seen it first hand on more than Q3. But hey PC gamers are at fault bragging about my 100+fps and not ever looking at how good their image quality is compared to others. I for one would rather have better image quality than high fps that cauuses me to lose image quality. Just my two cents...

maybe it was running at a higher quality level on the mac?

It does not have to do with settings in quake. Ive been a long time quake guru, and have controlled every setting possible. I also know, it doesn't have to do with graphics hardware or drivers. There must be some different opengl rendering techniques throughout the OSes. I don't know what these might be though. I do, however, think that these changes effect game geometry. I've seen this on many speeds of boxes in every quality setting, the graphics in quake are rendered differently between windows, linux, and Mac os X. In what way could an OS be rendering the opengl games differently?

It kind of pisses me off to know that however good of hardware I get, quake will always be the most fun on a shitty mac (not that I don't like macs....but).

The OpenGL code executing should be the same on Linux, Mac, Windows. Any differences are most likely caused by driver implementation differences.

As an example, the archway may have been done using OpenGL quadrics calls. Thus the code calls something like gluDisk(quadratic,0.5f,1.5f,...) but the driver tesselates and calculates the polygons to be displayed.

Adherence to the OpenGL spec should minimize driver differences, but if the spec is not specific enough then the driver implementations might vary.

One would think that the drivers for all platforms for the same hardware would leverage common code, and therefore be identical across platforms for the same hardware, but I doubt that is the case. e.g. ATI linux drivers don't share much code with their Windows or Mac.

If it is the drivers, why would the most updated and used drivers (windows) render the game that much less visually apealing?

Are the graphics cards different? That might cause it to look worse in Windows.

"If it is the drivers, why would the most updated and used drivers (windows) render the game that much less visually apealing?"

This answer would vary from vendor to vendor. The only reason an implementation would choose something less visually appealing would be to improve performance. For example, if your card gets the fastest results in Doom III, but is not the best looking, a vendor might intentionally choose a more-performant, less-visually appealing code path in order to beat the competition numbers.

Since the hardware performance numbers in Windows would drive sales, one might implement more performant less visually appealing drivers there, while on the mac you might concentrate on visul quality.

Obviously, thus discussion is entirely theoretical.

By the way, what hardware are you using - nvidia or ati or other?

Well, an API such as D3D or OGL has strict rules an implementation has to adhere to. This is specifically done so to avoid differences between implementations and vendors. Especially OpenGL, working on multiple platforms and throughout different OS'es, is very clear about its behaviour. However, details in certain areas are left to the discretion of the implementor. A good example is the exact equations used to determine mipmap selection and interpolation. Using slightly different equations can create visually different results. FSAA is another such unspecified area.

It is often hard to define a common standard over these issues, since different manufacturers use very different technical frameworks and algorithms. IP and patents are another limiting factor (for example, this is the reason why Radeons won't filter shadowmaps in the FFP, unlike GeForces).

Most of those differences are limited to the graphics chipset though, and should therefore be independent of the OS and platform. Of course, drivers can also make a large difference, especially when they are optimized for maximal FPS readings. Sadly, many gamers buy on high performance figures alone, instead of comparing the visual quality.

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Original post by Yann L Well, an API such as D3D or OGL has strict rules an implementation has to adhere to. This is specifically done so to avoid differences between implementations and vendors. Especially OpenGL, working on multiple platforms and throughout different OS'es, is very clear about its behaviour. However, details in certain areas are left to the discretion of the implementor. A good example is the exact equations used to determine mipmap selection and interpolation. Using slightly different equations can create visually different results. FSAA is another such unspecified area. It is often hard to define a common standard over these issues, since different manufacturers use very different technical frameworks and algorithms. IP and patents are another limiting factor (for example, this is the reason why Radeons won't filter shadowmaps in the FFP, unlike GeForces). Most of those differences are limited to the graphics chipset though, and should therefore be independent of the OS and platform. Of course, drivers can also make a large difference, especially when they are optimized for maximal FPS readings. Sadly, many gamers buy on high performance figures alone, instead of comparing the visual quality.

Yes it is sad, cause I would rather have good IQ than FPS, as long as the fps were playable. I seen the difference on a GF2MX card on the Mac years ago. And I seen the image quality on games like Diablo2 and Warcraft 3. War3 on Mac when the hero levels up, is different looking than the PC its more pernounced I will say. You would have to see it to understand. I have had both platforms back and forth for the last 4 years, and had a PC since PC had 486s, and can say that the grahpics on Mac do look better, and Apple's stance on drivers is if IQ is degraded to gain speed they don't allow it. I like that... but some people don't. All in all the hardware on Mac and PC for videocards are the same only difference is drivers and on PC you have ATI or Nvidia who control them on Mac Apple has the final word on whether or not to allow the driver udpate...

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Original post by Roboguy Are the graphics cards different? That might cause it to look worse in Windows.

I've been over this: I've basically done controlled experiments with a variety of hardware.

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By the way, what hardware are you using - nvidia or ati or other?

This is another theme I see, no matter the hardware, the visual properties between the different OSes I described before are still in place. I know what you mean about the varience between vendors, but the visual themes still have the same platform differential. For example, I would go and load the quake demo on a slower mac at work, but there is still that constant look and seeming geometrical property it shares with the other macs ive played on before. This could make one stuck to an OS soley because of this stupid (specific) characteristic. I agree with MARS_999: "You would have to see it to understand".

Does apple, for example, insist on certain characteristics when graphics vendors like ati and nvidia are making their graphics drivers? I'd like to see quake on a wildcat, if it is only the graphics drivers changing the visual theme.

[Edited by - BSD on March 23, 2005 12:02:08 PM]

Bump, for the life on an important topic.

Still no screenshots...

There are two things I haven't seen mentioned. Macs have a different gamma than PCs usually. Macs tend to be quite a bit brighter. This could certainly fool the eye into seeing differences. Also, Quake 3 on the Mac is *very* optimized. Extensive work was done getting every possible FPS out of Q3 on the Mac side, and I wouldn't be surprised if it looked a little different because of it.