Difference between revisions of "Circle approximation"
From JSXGraph Wiki
Jump to navigationJump to searchA WASSERMANN (talk | contribs) |
A WASSERMANN (talk | contribs) |
||
| Line 8: | Line 8: | ||
var rot = brd.createElement('transform', [function() {return Math.PI*2.0/n.Value();},p0], {type:'rotate'}); // angle, rotation center | var rot = brd.createElement('transform', [function() {return Math.PI*2.0/n.Value();},p0], {type:'rotate'}); // angle, rotation center | ||
var ptmp = brd.createElement('point',[0,0],{visible:false,withLabel:false}); // dummy point for the rotation | var ptmp = brd.createElement('point',[0,0],{visible:false,withLabel:false}); // dummy point for the rotation | ||
| − | var | + | var cIn = brd.createElement('curve',[[],[]],{fillColor:'#ff3300',fillOpacity:0.5}); |
| + | var cOut = brd.createElement('curve',[[],[]],{fillColor:'#0033ff',fillOpacity:0.5}); | ||
| − | + | cIn.updateDataArray = function() { | |
var i; | var i; | ||
this.dataX = [p1.X()]; | this.dataX = [p1.X()]; | ||
| Line 21: | Line 22: | ||
} | } | ||
} | } | ||
| + | |||
| + | cOut.updateDataArray = function() { | ||
| + | var i; | ||
| + | var s = circ.getRadius()/Math.cos(Math.PI*2.0/n.Value); | ||
| + | this.dataX = [p0.X()+s]; | ||
| + | this.dataY = [p0.Y()]; | ||
| + | ptmp.setPositionDirectly(JXG.COORDS_BY_USER, p0.X()+s,p0.Y()); | ||
| + | for (i=0;i<n.Value();i++) { | ||
| + | rot.applyOnce(ptmp); | ||
| + | this.dataX.push(ptmp.X()); | ||
| + | this.dataY.push(ptmp.Y()); | ||
| + | } | ||
| + | } | ||
| + | |||
| + | |||
brd.update(); | brd.update(); | ||
