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Index › Programming Questions & Help › Syntax Questions › draw an arrow

joridegoede YaBB Newbies Offline Posts: 2	draw an arrow Aug 24th, 2008, 9:57pm   Hi, I'm trying to create a function that draws an arrow (a line with an arrow head at the end) from point x1, y1 to x2, y2 but I don't have enough knowledge about the math to do it. Can someone help me out? Thanks! Jori

antiplastik YaBB Moderator Offline Posts: 699 France	Re: draw an arrow Reply #1 - Aug 24th, 2008, 11:02pm   maybe something like this : Code: // draw the line line(x1, y1, x2, y2); // draw a triangle at (x2, y2) pushMatrix(); rotate(atan2(y2-y1, x2-x1)); translate(x2, y2); triangle(0, 0, -10, 5, -10, -5); popMatrix(); hope it will work (I haven't tried).

joridegoede YaBB Newbies Offline Posts: 2	Re: draw an arrow Reply #2 - Aug 25th, 2008, 11:48am   Thanks a lot! That helped me out. Here is the arrow function: Code: void arrow(int x1, int y1, int x2, int y2) { line(x1, y1, x2, y2); pushMatrix(); translate(x2, y2); float a = atan2(x1-x2, y2-y1); rotate(a); line(0, 0, -10, -10); line(0, 0, 10, -10); popMatrix(); }