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Index › Programming Questions & Help › Syntax Questions › check if a point is inside or outside of a shape

snorpey YaBB Newbies Offline Posts: 35 Germany

check if a point is inside or outside of a shape Jul 10th, 2008, 1:34pm   hi. i want to check wheter or not an object with the coordianates xy is within a vertex shape or not. is there a simple way to calculate this? for instance i have a shape like this Code: beginShape(); vertex(30, 20); vertex(53, 20); vertex(85, 75); vertex(85, 75); vertex(30, 55); vertex(30, 20); endShape(); and want to check if the point(23, 76) is within the shape.

stuff i do

antiplastik YaBB Moderator Offline Posts: 699 France

Re: check if a point is inside or outside of a sha Reply #1 - Jul 10th, 2008, 2:00pm   java.awt.Polygon provides a contains(int x, int y) method which is appropriate for what you want to do. javadoc reference : http://java.sun.com/j2se/1.4.2/docs/api/java/awt/Polygon.html Quote: // create the polygon java.awt.Polygon p = new java.awt.Polygon(); p.addPoint(30, 20); p.addPoint(53, 20); p.addPoint(85, 75); p.addPoint(85, 75); p.addPoint(30, 55); p.addPoint(30, 20); // check if point is inside println(p.contains(23, 76)); // draw the polygon beginShape(); for (int i = 0; i < p.npoints; i++) {  vertex(p.xpoints[i], p.ypoints[i]); } endShape();