id's "Rage" engine, Tech5 is OpenGL based

Contrary to earlier reports the current Tech5 code is OpenGL based.

Carmack is open to a port to D3D based on secondary factors just as he is open to a port to OpenGL 3.

Just thought I’d share since false information has been widely circulated on this issue including on these forums.

Doesn’t surprise me a bit. If OpenGL 3.0 wasn’t on the horizon, i would switch to D3D, too. So he’s basically doing the same thing most of us do: Wait and hope for a great new API. BTW, does anyone know, whether the ARB will be able to keep their promise, about having “something” ready until the end of September?


BTW, does anyone know, whether the ARB will be able to keep their promise, about having “something” ready until the end of September?
They didn’t say something; they said the spec.

And no, I think they’ve been pretty quiet on the subject. But, then again, there’s a newsletter due out in 9 days that will shed light on the subject, one way or another.

Note to ARB: we will (happily) accept the GL 3.0 specification in lieu of a vol 5 newsletter.

Will there be a party? :slight_smile:

According to the BOF presentation at SIGGRAPH, the ARB should have finalized all open issues by the end of August. Which means at this point, it’s all about wording and actually writing the spec.

Jan there’s some irony to your post in the context of a situation where people were previously saying he’s already committed to D3D. He’s not saying he’ll switch to D3D, he’s saying he’s keeping his options open, and secondary factors will influence the final determination.

I’ve seen Carmack say elsewhere that DX10 doesn’t change much from his perspective and Tech 5 will be targeting DX 9 class hardware.

On the spec front I really don’t see D3D 10 pressuring a rush to OpenGL 3, especially after recent developments but the sooner the better.

The PC version is still OpenGL, but it is possible that could change before release. The actual API code is not very large, and the vertex / fragment code can be easily translated between cg/hlsl/glsl as necessary. I am going to at least consider OpenGL 3.0 as a target, if Nvidia, ATI, and Intel all have decent support. There really won’t be any performance difference between GL 2.0 / GL 3.0 / D3D, so the api decision will be based on secondary factors, of which inertia is one.

dorbie: True. I only interpret it this way: “D3D9 is very good, it works well on the PC and the 360. OpenGL 2.x is a mess, but it is currently still good enough. Until release that could change (especially since ATI and nVidia might not work on their OpenGL drivers much, if even an id-Engine might not use it anymore). However, if OpenGL 3.0 is as good as expected AND THERE ARE GOOD ENOUGH DRIVERS, id Tech 5 will most certainly use OpenGL 3.0 (or one might be able to select the render API on the PC).”

I do think, that OpenGL 3.0 needs to be out soon, because it will take some time to get stable and fast drivers. Currently D3D10 is no threat, so we still got some time, but the situation will change. (In this business usually sooner than later.)


Jan, in that case I don’t think “interpret” means what you think it means. :slight_smile:

I can’t believe he listed Intel.

Jan, what are you talking about? He is aiming for multiplatform support so ID has no choice to support 3 APIs.

D3D on the xbox platform, LibGCM on the PS3 and OpenGL on the Mac
Add to that Linux : GL
On Windows, they will likely just offer GL

I was only talking about the windows-version. Nothing else. On windows it can be OpenGL 2.x, 3.0 or D3D9 (or even two of em). And the question is, which one it will be, because if it ain’t OpenGL, it is bad news for us.


Originally posted by Jan:
And the question is, which one it will be, because if it ain’t OpenGL, it is bad news for us.

It will more than likely be openGL for windows, the reason being that the D3D for xbox360 and windows is not exactly 100% compatible (at least not in the way you use it) and will have to be worked on to make it work well.
While the mac version is almost identical to the linux and windows variants.

Also seeing as it is already running with GL on the windows platform it’s a fair bet that it will stay that way, unless openGL 3 comes out in time and proves to have a better texture management system from his viewpoint, in which case he might consider switching to that.
I do see him trying it out just to see if it can be done.

Unless we get faster GL implementations on Vista, I think OpenGL is living on borrowed time on Windows - but considering the tight integration between d3d and aero, I don’t think OpenGL can ever regain the edge it once had. We’re already getting customers wanting us to deliver our software on Vista setups, and I can imagine Carmack is thinking more than a year ahead, unlike us. GL on Vista is not running at acceptable speeds.

GL on Vista is not running at acceptable speeds.
Is it?

The most I’ve heard is that GL running windowed in Vista isn’t running at acceptable speeds, and even that’s somewhat debatable depending on the specific driver. GL running fullscreen in Vista seems to be running reasonably well (considering that Vista itself can impose a small performance penalty).

Now, I do recall a post or something from nVidia about how their drivers under the XP driver model used to perform a “flush” operation frequently that was fast under that driver model but slow under the Vista model. That would be a problem, but one I would expect to be corrected as IHVs produce more mature Vista drivers.

In any case, I suspect that the nature of GL 3.0’s context framebuffer (which is the primary interface point between D3D and Aero) will allow it to behave similarly to a regular D3D renderer. As for other driver-dependent behavior, I suspect that the nature of GL 3.0’s API, in terms of how you render with it and so forth, would allow drivers to be more streamlined in such things.

Well then, I must be imagining things because I haven’t read what you’ve read, I’ve only practical experience of the problem.

Just as well that Vista is tanking then, if it’s too slow you can always downgrade with Microsoft’s new downgrade path (but of course there’s NOOOOOTHING wrong with Vista, no sirree).

As for performance … even D3D takes a hit on Vista, and drivers can do a lot under the covers, it boils down to priorities and breadth of support. I still think OpenGL gets enough attention and the multiple API support required is actually less divergent than it was. OpenGL 3 will help further.

Well then, I must be imagining things because I haven’t read what you’ve read, I’ve only practical experience of the problem.
Just curious: Have you compared GL/XP to GL/Vista or have you compared D3D/Vista to GL/Vista? If the latter, have you done a similar comparison D3D/XP to GL/XP, to eliminate user code differences?

The former.

D3D apps have no advantage over OpenGL apps when running in a window under Aero. Just because Aero uses D3D[9Ex] does not mean that D3D apps will run better or faster.

As far as the driver model goes on Vista, there’s not a lot that can be done to help either API out from an application’s point of view. The driver is given an off-screen texture to render into and the desktop (DWM) manages when that buffer gets presented to the user. That’s how blurred title bars, Flip3D, etc. are handled. Frame rates are limited by the application’s frame rate plus the DWM’s frame rate.

This has SPECviewperf benchmark on Quadro FX 5500
of course, drivers have changed since back then
look at page 6, 7.
SPECviewperf benchmark on ATI X1900XTX, cat 7.1
This bench is very old but it’s as though there is no acceleration at all.

I would love too see these benches repeated with new drivers.