DDS_PIXELFORMAT structure

Surface pixel format.

Syntax

struct DDS_PIXELFORMAT {
  DWORD dwSize;
  DWORD dwFlags;
  DWORD dwFourCC;
  DWORD dwRGBBitCount;
  DWORD dwRBitMask;
  DWORD dwGBitMask;
  DWORD dwBBitMask;
  DWORD dwABitMask;
};

Members

dwSize

Type: DWORD

Structure size; set to 32 (bytes).

dwFlags

Type: DWORD

Values which indicate what type of data is in the surface.

Flag	Description	Value
DDPF_ALPHAPIXELS	Texture contains alpha data; dwRGBAlphaBitMask contains valid data.	0x1
DDPF_ALPHA	Used in some older DDS files for alpha channel only uncompressed data (dwRGBBitCount contains the alpha channel bitcount; dwABitMask contains valid data)	0x2
DDPF_FOURCC	Texture contains compressed RGB data; dwFourCC contains valid data.	0x4
DDPF_RGB	Texture contains uncompressed RGB data; dwRGBBitCount and the RGB masks (dwRBitMask, dwGBitMask, dwBBitMask) contain valid data.	0x40
DDPF_YUV	Used in some older DDS files for YUV uncompressed data (dwRGBBitCount contains the YUV bit count; dwRBitMask contains the Y mask, dwGBitMask contains the U mask, dwBBitMask contains the V mask)	0x200
DDPF_LUMINANCE	Used in some older DDS files for single channel color uncompressed data (dwRGBBitCount contains the luminance channel bit count; dwRBitMask contains the channel mask). Can be combined with DDPF_ALPHAPIXELS for a two channel DDS file.	0x20000

dwFourCC

Type: DWORD

Four-character codes for specifying compressed or custom formats. Possible values include: DXT1, DXT2, DXT3, DXT4, or DXT5. A FourCC of DX10 indicates the prescense of the DDS_HEADER_DXT10 extended header, and the dxgiFormat member of that structure indicates the true format. When using a four-character code, dwFlags must include DDPF_FOURCC.

dwRGBBitCount

Type: DWORD

Number of bits in an RGB (possibly including alpha) format. Valid when dwFlags includes DDPF_RGB, DDPF_LUMINANCE, or DDPF_YUV.

dwRBitMask

Type: DWORD

Red (or luminance or Y) mask for reading color data. For instance, given the A8R8G8B8 format, the red mask would be 0x00ff0000.

dwGBitMask

Type: DWORD

Green (or U) mask for reading color data. For instance, given the A8R8G8B8 format, the green mask would be 0x0000ff00.

dwBBitMask

Type: DWORD

Blue (or V) mask for reading color data. For instance, given the A8R8G8B8 format, the blue mask would be 0x000000ff.

dwABitMask

Type: DWORD

Alpha mask for reading alpha data. dwFlags must include DDPF_ALPHAPIXELS or DDPF_ALPHA. For instance, given the A8R8G8B8 format, the alpha mask would be 0xff000000.

Remarks

To store DXGI formats such as floating-point data, use a dwFlags of DDPF_FOURCC and set dwFourCC to 'D','X','1','0'. Use the DDS_HEADER_DXT10 extension header to store the DXGI format in the dxgiFormat member.

Note that there are non-standard variants of DDS files where dwFlags has DDPF_FOURCC and the dwFourCC value is set directly to a D3DFORMAT or DXGI_FORMAT enumeration value. It is not possible to disambiguate the D3DFORMAT versus DXGI_FORMAT values using this non-standard scheme, so the DX10 extension header is recommended instead.

Requirements

See also

Reference for DDS