Difference between revisions of "Restrict points to limited area"

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 +
Restrict the points A, B, and C to the lower left quadrant.
 
<jsxgraph width="600" height="600">
 
<jsxgraph width="600" height="600">
 
var brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,5,5,-5], axis:true});
 
var brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,5,5,-5], axis:true});
Line 25: Line 26:
 
===The underlying JavaScript code===
 
===The underlying JavaScript code===
 
<source lang="javascript">
 
<source lang="javascript">
 +
var brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,5,5,-5], axis:true});
 +
var A = brd.create('point', [-1,-1], {name:'A'});
 +
var B = brd.create('point', [-3, -3], {name:'B'});
 +
var C = brd.create('point', [ -2, 0], {name:'C'});
 +
 +
brd.on('move', function() {
 +
  var list = [A, B, C], i;
 +
 +
  brd.suspendUpdate();
 +
  for (i = 0; i < list.length; ++i) {
 +
      list[i].moveTo(
 +
          [
 +
            Math.min(0, list[i].X()),
 +
            Math.min(0, list[i].Y())
 +
          ]
 +
        );
 +
  }
 +
  brd.unsuspendUpdate();
 +
});
 +
 
</source>
 
</source>
  
 
[[Category:Examples]]
 
[[Category:Examples]]

Latest revision as of 11:47, 18 June 2013

Restrict the points A, B, and C to the lower left quadrant.

The underlying JavaScript code

var brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-5,5,5,-5], axis:true});
var A = brd.create('point', [-1,-1], {name:'A'});
var B = brd.create('point', [-3, -3], {name:'B'});
var C = brd.create('point', [ -2, 0], {name:'C'});

brd.on('move', function() {
   var list = [A, B, C], i;

   brd.suspendUpdate();
   for (i = 0; i < list.length; ++i) {
       list[i].moveTo(
           [
            Math.min(0, list[i].X()), 
            Math.min(0, list[i].Y())
           ]
         );
   }
   brd.unsuspendUpdate();
 });