HDR on 6800`s in crytek`s demo - The Project

[DOGMA1138]

is it still being done by 16fp blending?

 

[Apple740]

Afaik only Ati card's can have (MRT) HDR in the Crytek demo, it doesn't contain Nv's openexr.

 

[Guden Oden]

Um, openexr is a file format for "deep" still images. It's not a rendering method for realtime 3D graphics.

 

[Mate Kovacs]

Nv's FP16 format is equivalent to the "half" data type introduced by ILM's OpenEXR. Thus the names are often mixed up.

 

[pat777]

Afaik only Ati card's can have (MRT) HDR in the Crytek demo, it doesn't contain Nv's openexr.

Strange, the NV4x series supports MRTs.
http://download.nvidia.com/developer/GPU_Programming_Guide/GPU_Programming_Guide.pdf
Go to pages 39 and 40.

 

[Demirug]

Afaik only Ati card's can have (MRT) HDR in the Crytek demo, it doesn't contain Nv's openexr.

If you disable the NV40 FP16 rendertarget support the cryengine switch to MRT HDR even on a NV40. But it looks like that the MRT "HDR" support is not full implemented yet. I any case I am not sure if we can call this technology still HDR because it do not render the frame to a HDR buffer.

 

[Demirug]

Afaik only Ati card's can have (MRT) HDR in the Crytek demo, it doesn't contain Nv's openexr.

Strange, the NV4x series supports MRTs.
http://download.nvidia.com/developer/GPU_Programming_Guide/GPU_Programming_Guide.pdf
Go to pages 39 and 40.

Why should this strange?

The DirectX spec say that every chip with pixelshader 3.0 have to support MRT with 4 targets. There are some other caps that a SM 3 chip must support.

 

[pat777]

Afaik only Ati card's can have (MRT) HDR in the Crytek demo, it doesn't contain Nv's openexr.

Strange, the NV4x series supports MRTs.
http://download.nvidia.com/developer/GPU_Programming_Guide/GPU_Programming_Guide.pdf
Go to pages 39 and 40.

Why should this strange?

The DirectX spec say that every chip with pixelshader 3.0 have to support MRT with 4 targets. There are some other caps that a SM 3 chip must support.

I'm meant it's strange that MRT hdr didn't work on 6800s but you cleared things up.

 

[Demirug]

Afaik only Ati card's can have (MRT) HDR in the Crytek demo, it doesn't contain Nv's openexr.

Strange, the NV4x series supports MRTs.
http://download.nvidia.com/developer/GPU_Programming_Guide/GPU_Programming_Guide.pdf
Go to pages 39 and 40.

Why should this strange?

The DirectX spec say that every chip with pixelshader 3.0 have to support MRT with 4 targets. There are some other caps that a SM 3 chip must support.

I'm meant it's strange that MRT hdr didn't work on 6800s but you cleared things up.

Misunderstanding.

The reason is priority. FP16 HDR have an higher priority than MRT HDR in the cryengine.

 

[DOGMA1138]

ok thanks