Visual hull — where it appears
Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.
Three views do not fix the solid
A stepped block on a six-cell grid draws a front, a top and a side view. So does a solid with a third of its material, and so does one with more than the block has — 192 cells against 64, every filled square in all three views identical. The drawing office's triple bounds a part between two solids and does not determine it, and the gap runs to a factor of n.
The dish no outline reaches
An outline is a pair of numbers per direction and nothing more, so a shape built from outlines has two errors that behave differently. The part outside the convex hull falls as one over the square of the view count. The part inside a concavity is the same area at four views and at a hundred and twenty-eight, because no pair of supporting lines ever reaches into a bite.
Named alongside it
The objects these essays reach for when they reach for this one.
reconstruction ambiguitySilhouetteAffine mapContour generatorConvergence orderConvex hullDemonstrationElevationinstrument limitMultiview drawingnecessary, not sufficientOrthographic