Incremental Rendering of Textures in Perspective
Alvy Ray Smith · 2000
An incremental, scanline-ordered algorithm for rendering a 2-dimensional texture into a planar convex polygon embedded in 3-space is presented. The textured polygon is projected into a viewing plane where it is seen in perspective. The method is shown to cost a divide and two lerps per pixel more than the wellknown incremental algorithm for rendering an orthographic view of a texture or a perspective view of a “texture” consisting of a single color (lerp = linear interpolation). It is argued that the divide is necessary—that, for example, secondorder incrementing is not good enough in general.