Doom 3 Engine incapable of custom fragment programs?

[AlNom]

The most expedient sounding option was to just use the Nvidia
extensions that they implement, NV_vertex_program and NV_register_combiners,
with seven texture units instead of the four available on GF3/GF4.

The dev team did some research and found back doors and even a few undocumented instructions for the NV2X, allowing them to write custom shaders for the Xbox GPU which have improved performance to an exceptional level. The standard seven passes required to render a single frame in Doom III were reduced to four passes;

What do you mean by this? When programming for the Xbox, developers have very low-level access to the hardware, and thus can sometimes do quite a bit more than they can on a PC with similar hardware.

The thing I meant to look for is bolded.. I was wondering if these are the same thing. Just confused by the terminology (texture units versus passes...). The sevens and fours just got me thinking they were the same.

 

[KimB]

This may be really old news, But did anyone know Doom 3 engine has beta support for Nvidias implementation of HDR?

nVidia doesn't have an implementation of HDR. An implementation of HDR may use nVidia's support for FP16 blending, however.

 

[KimB]

Alstrong: Quote one deals with different hardware entirely, the 3DLabs P10, which supports nVidia's NV2x OpenGL extensions, but essentially has no limits in the hardware.

Quote two just states that they were able to be a little bit more efficient on X-Box hardware, and is completely unrelated to quote one.

 

[AlNom]

Chalnoth:

Thanks for clearing that up.

 

[XxStratoMasterXx]

This may be really old news, But did anyone know Doom 3 engine has beta support for Nvidias implementation of HDR?

Just read this over at nvnews.

http://www.nvnews.net/vbulletin/showthread.php?t=43691

The experimental code used pbuffers, and wasn't all that well integrated with the entire system, so no, it wouldn't be completely trivial for licensees to use it. I was also using the NV40 floating point blends, so supporting ATI cards and NV30 cards would require more code to do extra passes to simulate blending.

John Carmack

Yep!
I wonder why he's even going to bother writing any more code for the NV30 and R3xx and R4xx cards...(for his next engine)?

 

[_xxx_]

Because there are many people out there that don't buy every newest whiz-bang card as soon as it appears?

 

[XxStratoMasterXx]

Because there are many people out there that don't buy every newest whiz-bang card as soon as it appears?

The game won't be out for a while ;-)

But, i'm really happy D3 engine has support for HDR!