Re: bilinear filtering from a floating point texture, on Nvidia hardware?

No - if you use the internalformat hints from the ARB_texture_float 
extension (e.g. RGBA16F_ARB) instead of NV_float_buffer's FLOAT_RGBA_NV, 
you will get filtering.  (Make sure you test for the extension, as this 
is only available on GeForce 6x00 and newer, driver versions 75 and newer).

Matt Franklin wrote:

>Hi-- I'm just looking for a bit of clarification regarding bilinear
>filtering support under OpenGL vs. DirectX.
>
>
>The Nvidia GPU Programming Guide lists that it supports filtering from
>G16R16F and A16B16G16R16F texture formats (and it does not support
>filtering from other float formats, such as R32F).  However, the OpenGL
>extension NV_float_buffer documentation specifies:
>
>"Floating-point textures (those with a base internal format of
>FLOAT_R_NV, FLOAT_RG_NV, FLOAT_RGB_NV, or FLOAT_RGBA_NV) do not support
>texture filters other than NEAREST.  For such textures, NEAREST
>filtering is applied regardless of the setting of TEXTURE_MIN_FILTER."
>(A similar statement is supplied for TEXTURE_MAG_FILTER.)
>
>Am I correct in deducing that this means the 6 series hardware is
>capable of bilinear filtering from floating point textures, however,
>this functionality is only available using DirectX?
>
>----- 
>FAQ and OpenGL Resources at:
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>
>  
>