invalidate-rectangle-from-points Function

Summary

Invalidates a rectangle specified by two points, causing it to be redisplayed.

Package

graphics-ports

Signature

invalidate-rectangle-from-points port x1 y1 x2 y2 &key extend extend-x extend-y

Arguments

port⇩	A graphics port.
x1⇩, y1⇩, x2⇩, y2⇩	Real numbers.
extend⇩, extend-x⇩, extend-y⇩
	Real numbers.

Description

The function invalidate-rectangle-from-points invalidates a rectangle in port (by calling invalidate-rectangle) specified by two points. The coordinates of one point are (x1, y1) and the other (x2, y2) The points do not have to be ordered.

The keyword arguments specify extending the rectangle: extend-x extends the rectangle in the x dimension in both directions, and extend-y extends the rectangle in the y dimension in both directions. Both extend-x and extend-y default to extend, which itself defaults to 0 (that is, no extension).

invalidate-rectangle-from-points does not return a useful value.

See also

invalidate-rectangle