Quote:64-bit floating point HDR rendering supported throughout the pipeline Includes support for blending and multi-sample anti-aliasingIs this all marketing bullshit or what? Can someone confirm that you can have filtered floating point textures?
ATI Radeon 1900 XTX
Author
I just bought a new graphics card for work, the 1900 XTX, installed the latest drivers (6.3) and fired up DirectX Caps Viewer.
The caps viewer told me that I couldn't use filtering on any floating point textures.
WTF that was one of the main reasons for choosing this card!
According to this page:
AFAIK Filtering FP textures is not supported on ATi hardware directly (can do it in the shader obviously). MSAA and blending are supported though.
On NVIDIA cards there is filtering (with FP format and filter restrictions, not sure about all the details here) but blending and AA is not supported.
If I am mistaken then someone please correct me.
On NVIDIA cards there is filtering (with FP format and filter restrictions, not sure about all the details here) but blending and AA is not supported.
If I am mistaken then someone please correct me.
Quote:Original post by eq
I just bought a new graphics card for work, the 1900 XTX, installed the latest drivers (6.3) and fired up DirectX Caps Viewer.
The caps viewer told me that I couldn't use filtering on any floating point textures.
WTF that was one of the main reasons for choosing this card!
According to this page:Quote:64-bit floating point HDR rendering supported throughout the pipeline
Includes support for blending and multi-sample anti-aliasing
Is this all marketing bullshit or what?
Can someone confirm that you can have filtered floating point textures?
The sentence you quoted does not imply, in any way, that filtering floating point textures is supported. "Throughout the pipeline" means that the register precision is sufficient for the card to maintain 64-bit floating point values all the way until the frame buffer (which isn't much said, anyway, as Geforce FX 5200 can also perform this feat even with 128 bits per pixel).
Quote:On NVIDIA cards there is filtering (with FP format and filter restrictions, not sure about all the details here) but blending and AA is not supported.
The 6000 and 7000 cards actually do support FP blending.
Author
Quote:Original post by Nik02Quote:Original post by eq
I just bought a new graphics card for work, the 1900 XTX, installed the latest drivers (6.3) and fired up DirectX Caps Viewer.
The caps viewer told me that I couldn't use filtering on any floating point textures.
WTF that was one of the main reasons for choosing this card!
According to this page:Quote:64-bit floating point HDR rendering supported throughout the pipeline
Includes support for blending and multi-sample anti-aliasing
Is this all marketing bullshit or what?
Can someone confirm that you can have filtered floating point textures?
The sentence you quoted does not imply, in any way, that filtering floating point textures is supported. "Throughout the pipeline" means that the register precision is sufficient for the card to maintain 64-bit floating point values all the way until the frame buffer (which isn't much said, anyway, as Geforce FX 5200 can also perform this feat even with 128 bits per pixel).
You're right, feeling stupid now, but somehow I got the impression from elsewhere.
Thanks for the info, trying to locate this hotfix, whar does it fix actually?
From Beyond3D's X1800 review:
I guess that hasn't changed with the X1900.
Quote:
Texture processing is achieved in a similar fashion to ATI's previous parts. Although the earlier pipeline diagram indicates a texture sampler array, all the the texture units are not re-allocatable to different pipelines, instead 4 are dedicated to each of the quads. At present ATI see the primary use of float texture sampling as being for lookup data, which only requires point sampling, and so at present haven't put floating point texture filtering in place, instead relying on filtering in the shader if required - at present the developer has to code this, however if they have a demand for it they may roll it up into the driver.
I guess that hasn't changed with the X1900.
You might want to look into ATI's Fetch4 functionality btw to make filtering in the shader more efficient for single component FP textures. I don't know how you access this functionality in D3D - I expect there's something about it on ATI's developer site.
If you're doing HDR, also check out the related paper in the latest ATI SDK for information on good ways to implement it, and some alternative texture formats for the points where filtering is useful.
Of course you can also implement it in the shader...
Of course you can also implement it in the shader...
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