Ray tracing method and apparatus for projecting rays through an object represented by a set of infinite surfaces

摘要

Each object in a 3-dimensional image to be displayed may be represented by a set of infinite surfaces. Each elementary area of a screen on which the image is to be displayed has a ray projected through it onto the 3-dimensional image. The location of the intersection of the projected ray with each surface is then determined and from these locations it is determined whether any intersected surface is visible at that elementary area. The elementary area is then shaded for display in dependence on the result of the determination.