# Perspective -- Set the amount of perspective

## Description

A 4x4 matrix that is applied to 3d coordinates for perspective. After this transformation, the coordinates must be up to normalization $(x,y,z,p)$ where $(x,y,z>0)$ are coordinates in the reference frame where the observer is at the origin looking in the $z$ direction, and $p$ is the distance from the observer to the screen. One can instead provide a real number $p$, which is equivalent to placing the screen centered at $z=0$ and the viewer at $(0,0,p)$. Only has an effect if in the outermost VectorGraphics object.

## For the programmer

The object Perspective is .