Microsoft DirectX 8.1 (Visual Basic) |
A volume texture is an extension of the standard texture for Microsoft® DirectX® 8.x, and can be defined with or without mipmaps. If a file contains a volume texture, DDSCAPS_COMPLEX, DDSCAPS2_VOLUME, DDSD_DEPTH, and dwDepth should be set. For volumes without mipmaps, each depth slice is written to the file in order. If mipmaps are included, all depth slices for a given mipmap level are written together, with each level containing half as many slices as the previous level with a minimum of 1. Volume textures do not support DXTn compression as of DirectX 8.0.
For example, a 64 x 64 x 4 volume map, a pixel format of R8G8B8 (3 bytes per pixel), and all mipmap levels would contain:
"DDS ", (64, 64, 4), (pitch=768), (pixel format=R8G8B8, bitcount=24), (mipmapcount=7), (DEPTH, TEXTURE, PITCH, COMPLEX, MIPMAP, VOLUME, RGB) | 128 bytes |
64 x 64 slice 1 of 4 main image. | 12288 bytes |
64 x 64 slice 2 of 4 main image. | 12288 bytes |
64 x 64 slice 3 of 4 main image. | 12288 bytes |
64 x 64 slice 4 of 4 main image. | 12288 bytes |
32 x 32 slice 1 of 2 mipmap image. | 3072 bytes |
32 x 32 slice 2 of 2 mipmap image. | 3072 bytes |
16 x 16 slice 1 of 1 mipmap image. | 768 bytes |
8 x 8 slice 1 of 1 mipmap image. | 192 bytes |
4 x 4 slice 1 of 1 mipmap image. | 48 bytes |
2 x 2 slice 1 of 1 mipmap image. | 12 bytes |
1 x 1 slice 1 of 1 mipmap image. | 4 bytes |