Mipmaps are pre-computed, smaller versions of textures that are shown in place of the full resolution texture at a distance and at shear angles.
The StaticTexture2D component provides some options for controlling mipmaps, including the following:
Mipmaps
Mipmaps are enabled by default and automatically calculate for you. This will result in a roughly 36% increase of VRAM usage per texture, but mipmaps help improve performance and visual fidelity, despite the increase in VRAM usage.
In some situations, such as textures or cubemaps used in Projection360 materials, mipmaps are practically never seen. In these situations, you can safely disable mipmaps to reduce overall VRAM usage. This is most common with skyboxes.
However, there are some exceptions where you still want to keep mipmaps enabled:
- PBS Metallic samples mipmaps from the cubemap on reflection probes for different smoothness values
- Xiexe Toon samples mipmaps from the matcap texture for different glossiness values.
MipMapBias
The bias of the mipmaps refers to how "far away" the mipmaps will be seen from. Decreasing the bias will "push" mipmaps further away, while increasing the bias will "pull" them closer. This can help alleviate textures being sharper or blurrier than intended at a distance and at harsh angles.
KeepOriginalMipMaps
DDS texture files can contain mipmaps. Enabling this option will use the mipmaps provided in a DDS file instead of the mipmaps that are computed for you. This has no effect on other image formats.
MipMapFilter
The filter type determines how textures are downscaled for their mipmap creation. This has no impact on general performance, only the initial generation of the mipmaps.
Bilinear
Softest filtering option, This option blurs the image with bilinear interpolation.
Box
Default for all 2D textures. This is the fastest option as no interpolation is involved and provides a balance between smoothness and sharpness.
Lanczos3
Sharpest filtering option. This option can provide the sharpest mipmaps out of the available options, but takes longer to generate and often looks identical to Box filtering.