During rendering, the mipmaps are used for textures that are distant. To render a given texture, the system generally computes how big it appears on screen, and then interpolates between the mipmap bigger and smaller than this size to produce texture information quickly. This behavior can be controlled by the materials sections within BRRES files.
If at least one size (width or height) is odd, a more complicated algorithm is needed. Wiimms SZS Tools support 2 algorithms for this case, one old and fast algorithm and one newer and smarter algorithm.
The fast algorithm only uses whole pixel of the source to crate a new destiantion pixel.
For example, we have an image of 9x5 pixels (red and blue squares) that must be resized to 4x2 pixels (yellow frames). The number of source pixels used for a single destination pixel varies between 4 to 9. For diagonal lines or shapes, the result may look unnatural.
The smart algorithm split the source image into equal sizes rectancles and break virtually a single pixel into peaces.
The new color is calculated by the average of all source pixels with weights. Here, each destination pixel is created by 5.625 source pixels. This kind of calculation makes the smart algorithm slower (factor 2–4) compared to the fast algorithm, but the resized images (mostly mipmaps) look most likely better.
|--mipmaps||If reading a source, scan for mipmaps and load them too. For PNG files, files named
|--no-mipmaps||If reading a source, ignore mipmaps. This disables not the creation of mipmaps (see -n-mipmaps).
|--n-mipmaps||num||Force the number of mipmaps. Values between 0 and 20 are allowed. Value
|--max-mipmaps||num||Control the automatic mipmap creation. Values between 0 and 20 are allowed and the default is 4. The mipmap creation for an image stops, if the set number is reached. This option is ignored, if
|--mipmap-size||num||Define the minimal width and minimal height of a generated mipmap. Any value >0 is allowed. The default is 8. This option is ignored, if
|--fast-mipmaps||If resizing an image, use the old fast resize algorithm (default until v1.64a) instead of the new smart one. Both algorithms differ only, when creating a mipmap for images with odd width or odd height. The old algorithm is faster (factor 2-4) than the default algorithm, but the new algorithm creates better resized images.