Intel working on Larrabee 2.

Discussion in 'Architecture and Products' started by nAo, Oct 4, 2008.

  1. nAo

    nAo Nutella Nutellae
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    oDepth has been available since DX8 IIRC!
     
  2. Jawed

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    Yeah, that is the point I was trying to get across.

    As for swizzling, I presume that's purely an ALU pipeline problem: swizzling + masking, D3D10 introduced all the "integer" and bit-wise instructions needed to do this, I think. The cache-hierarchy + memory I/O + compression hardware just see blobs of 32- or 128-bits (not sure...)

    I meant reading the existing Z then changing it, as opposed to merely overwriting by setting oDepth. Likening this RMW to blending colour in a render target, except with Z or stencil.

    I have to admit I don't understand how fast-Z and writing oDepth are going to work together. I'd forgotten D3D11 supports that.

    Jawed
     
  3. nAo

    nAo Nutella Nutellae
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    If you can guarantee that any depth value you write via oDepth is farther away from the camera than the 'canonical' z value than the hardware can still perform conservative early z-test.
     
  4. TimothyFarrar

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    Silly me, forgot the word "conservative" in front of oDepth...

    While I'm at it, the word swizzle is too abused and means many different things. What I was referring to prior was something which does address=TextureAddressOf(int x, int y) for "tiled" or "swizzled" textures... and this would definitely be something you want in hardware.
     
    #64 TimothyFarrar, Oct 15, 2008
    Last edited by a moderator: Oct 15, 2008
  5. Jawed

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    Knowing that ATI does range-based hierarchical early-Z culling, I'm fearful that this concept of "conservative" is not actually conservative enough.

    Jawed
     
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