Visual Plane
every picture states the point it is correct from
Concept

Back projection — where it appears

2 essays name this object, across 2 fields. What follows is each of them, and the objects they name alongside it.
horizoncorner angles90.000° — forced by the methoddepicted side ratio0.7195lens this drawing implies60° acrossdrawn exactly as the method prescribesthe free step is where the far edges go

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.

wrong · cubebyeye near edge 155 pxfar edge 196 pxrecovered: ratio 1.000000, corners 1e-14° from squarecorrect from 12 cm, at 160 mm wideplane tilted -45°

An inverse perspective is a leaning plane

Ask a divergent construction what solid it depicts and it answers: a rectangle, four right angles, near edge equal to far. What the splay encodes is not the shape but the plane's tilt — and a real square on a plane leaning toward the camera really does photograph with its far edge wider.

choices · divergence

Named alongside it

The objects these essays reach for when they reach for this one.

Depicted rectangleVanishing pointCamera tiltDemonstrationFocal lengthFocal recoveryFree parameterHorizonInverse perspectiveMeasuring pointone-point perspectivePicture plane

All concepts