Coordinate Transformations

Clip coordinates for a vertex result from shader execution, which yields a vertex coordinate
Position.

Perspective division on clip coordinates yields normalized device coordinates, followed by a viewport transformation (see Controlling the Viewport) to convert these coordinates into framebuffer coordinates.

If a vertex in clip coordinates has a position given by

( xc, yc, zc, wc )

then the vertex’s normalized device coordinates are

(xd, yd, zd) = ((xc/wc), (yc/wc), (zc/wc))