two-point construction — where it appears
The cube that is a box
The two-point cube every book teaches has a step it supplies no construction for. Place the two far edges symmetrically and the drawing depicts a cube for free; place them eight points apart — a difference invisible on the page — and it depicts a box 1.4 times shallower than it is wide.
The picture whose lines spread
In a Byzantine icon the sides of a table diverge with depth. The standard account says the vanishing point is behind the viewer. It is not — it sits below the near edge, in front of the eye, and it is the vanishing point of a direction running down and away.
Named alongside it
The objects these essays reach for when they reach for this one.
Depicted rectangleVanishing pointBack projectionDemonstrationDrawing systemFocal lengthFocal recoveryFree parameterHorizonInverse perspectiveMeasuring pointone-point perspective