editor / positionKeepingPoint
Function: positionKeepingPoint()
positionKeepingPoint(
box,local,drawn):Point
Defined in: model/position-keeping-point.ts:26
Position of a turned box such that one of its points is drawn at a given point of the SVG: b = P − (k + R(l − k)), k the half size of the box, l the point relative to the top-left of the box before it turns, R the turn about the center (DERIV-turned-shape step 5). The shape is rigid under the turn: every other point keeps its place relative to that one.
Parameters
box
angle, width and height of the box
local
the point, relative to the top-left of the box before it turns
drawn
where it must be drawn, in the SVG
Returns
the top-left of the box before it turns
Kind
domain
See
DERIV-turned-shape