Point restrictions in a plane

PGvdVeen shared this question 9 years ago

We have discussed it before: How to restrict the dragging of a point to a defined area.

This is necessary in many geometrical constructions, f.e. many examples of Geometric Places.

It applies to almost any geometric applet.

We can restrict a point to an invisible line segment.

It would be great if we could also restrict a point into a certain area.

A limitation to a convex, or even convex regular area is acceptable. (Square, triangle, rectangle or circle)

All solutions given over the years like covering an area with a linesegment are not very general.

I suggest some kind of command like P=RestrictedArea[c,inside/outside] which defines P inside or outside a circle c or a square s or a rectangle r.

Would this be possible?


Comments (1)



in 4.0 it is possible already

pointin[<region>] for polygon, circle, ellipse, convex zone of hiperbola, inequations....

for more strange restrictions you can use dynamiccoordinates like this file



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