Editing Texture mapping (section)

====Inverse texture mapping====
With this method, a pixel on the screen is mapped to a point on the texture. Each vertex of a [[rendering primitive]] is projected to a point on the screen, and each of these points is [[UV mapping|mapped to a u,v texel coordinate]] on the texture. A rasterizer will interpolate between these points to fill in each pixel covered by the primitive.

The primary advantage is that each pixel covered by a primitive will be traversed exactly once. Once a primitive's vertices are transformed, the amount of remaining work scales directly with how many pixels it covers on the screen.

The main disadvantage versus forward texture mapping is that the [[memory access pattern]] in the [[texture space]] will not be linear if the texture is at an angle to the screen. This disadvantage is often addressed by [[texture cache|texture caching]] techniques, such as the [[swizzled texture]] memory arrangement.

The linear interpolation can be used directly for simple and efficient [[#Affine texture mapping|affine]] texture mapping, but can also be adapted for [[#Perspective correctness|perspective correctness]].