Mipmap Bias (mipmap bias / MipMapBias) is a technical term that is extremely important in the rendering and optimization of game graphics (technical art). In the Mipmap system, which reduces texture resolution according to the distance from the camera, a technology that manually shifts the resolution switching boundary (bias value) to fine-tune the sharpness and blur of the texture.
Real-world analogy: To prevent distant billboards from becoming blurry due to poor eyesight, wear sharp glasses with a slightly stronger prescription (negative bias) in advance to correct the focus so that you can clearly see far away
By manually shifting the boundary line standard, which automatically reduces the image according to the distance from the camera, to a slightly farther side, even for slightly distant objects, a high-definition resolution texture that is one rank higher than usual is maintained, dramatically increasing the sharpness of the entire screen.
Figure: Mipmap Bias (Mipmap Bias / Infographic that clearly illustrates the basic processing flow and mechanism of MipMapBias) in Japanese.
Detailed mechanism and operating principle
Adjust the value of the "Mip Map Bias" parameter of the target texture in a negative direction (e.g. -0.5 or -1.0) to stretch the application range of the high-resolution texture far and sharpen it.