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D3DX_FILTER

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The following flags are used to specify which channels in a texture to operate on.

#define Description
D3DX_FILTER_NONE No scaling or filtering will take place. Pixels outside the bounds of the source image are assumed to be transparent black.
D3DX_FILTER_POINT Each destination pixel is computed by sampling the nearest pixel from the source image.
D3DX_FILTER_LINEAR Each destination pixel is computed by sampling the four nearest pixels from the source image. This filter works best when the scale on both axes is less than two.
D3DX_FILTER_TRIANGLE Every pixel in the source image contributes equally to the destination image. This is the slowest of the filters.
D3DX_FILTER_BOX Each pixel is computed by averaging a 2x2(x2) box of pixels from the source image. This filter works only when the dimensions of the destination are half those of the source, as is the case with mipmaps.
D3DX_FILTER_MIRROR_U Pixels off the edge of the texture on the u-axis should be mirrored, not wrapped.
D3DX_FILTER_MIRROR_V Pixels off the edge of the texture on the v-axis should be mirrored, not wrapped.
D3DX_FILTER_MIRROR_W Pixels off the edge of the texture on the w-axis should be mirrored, not wrapped.
D3DX_FILTER_MIRROR Specifying this flag is the same as specifying the D3DX_FILTER_MIRROR_U, D3DX_FILTER_MIRROR_V, and D3DX_FILTER_MIRROR_W flags.
D3DX_FILTER_DITHER The resulting image must be dithered using a 4x4 ordered dither algorithm.
D3DX_FILTER_SRGB_IN Input data is in sRGB (gamma 2.2) color space.
D3DX_FILTER_SRGB_OUT The output data is in sRGB (gamma 2.2) color space.
D3DX_FILTER_SRGB Same as specifying D3DX_FILTER_SRGB_IN | D3DX_FILTER_SRGB_OUT.

 

Each valid filter must contain exactly one of the following flags: D3DX_FILTER_NONE, D3DX_FILTER_POINT, D3DX_FILTER_LINEAR, D3DX_FILTER_TRIANGLE, or D3DX_FILTER_BOX. In addition, you can use the OR operator to specify zero or more of the following optional flags with a valid filter: D3DX_FILTER_MIRROR_U, D3DX_FILTER_MIRROR_V, D3DX_FILTER_MIRROR_W, D3DX_FILTER_MIRROR, D3DX_FILTER_DITHER, D3DX_FILTER_SRGB_IN, D3DX_FILTER_SRGB_OUT or D3DX_FILTER_SRGB.

Specifying D3DX_DEFAULT for this parameter is usually the equivalent of specifying D3DX_FILTER_TRIANGLE | D3DX_FILTER_DITHER. However, D3DX_DEFAULT can have different meanings, depending on which method uses the filter. For example:

  • When using D3DXCreateTextureFromFileEx, D3DX_DEFAULT maps to D3DX_FILTER_TRIANGLE | D3DX_FILTER_DITHER.
  • When using D3DXFilterTexture, D3DX_DEFAULT maps to D3DX_FILTER_BOX if the texture size is a power of two, and D3DX_FILTER_BOX | D3DX_FILTER_DITHER otherwise.

Reference each method to check for information about how D3DX_DEFAULT filter is mapped.

Constant Information

Requirement Value
Header d3dx9tex.h
Minimum operating system Windows 98

 

D3DX Constants