Bezier curves: Difference between revisions
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var removeSegment = function() { | var removeSegment = function() { | ||
brd.suspendUpdate(); | brd.suspendUpdate(); | ||
if (p.length>4) { | if (p.length>4) { | ||
brd.removeObject(p[p.length-1]); | |||
brd.removeObject(p[p.length-2]); | |||
brd.removeObject(p[p.length-3]); | |||
p.splice(p.length-3,3); | p.splice(p.length-3,3); | ||
} | } | ||
Revision as of 07:10, 29 September 2009
The red points are connected by a cubic Bezier curve. The blue points are the control points.
The underlying JavaScript code
var brd = JXG.JSXGraph.initBoard('jxgbox',{boundingbox:[-4,4,4,-4],keepaspectratio:true,axis:true});
var p = [];
col = 'red';
p.push(brd.createElement('point',[2,1],{strokeColor:col,fillColor:col})); // data point
col = 'blue';
p.push(brd.createElement('point',[0.75,2.5],{strokeColor:col,fillColor:col})); // control point
p.push(brd.createElement('point',[-0.3,0.3],{strokeColor:col,fillColor:col})); // control point
col = 'red';
p.push(brd.createElement('point',[-3,1],{strokeColor:col,fillColor:col})); // data point
col = 'blue';
p.push(brd.createElement('point',[-0.75,-2.5],{strokeColor:col,fillColor:col})); // control point
p.push(brd.createElement('point',[1.5,-2.8],{strokeColor:col,fillColor:col})); // control point
col = 'red';
p.push(brd.createElement('point',[2,-0.5],{strokeColor:col,fillColor:col})); // data point
var c = brd.createElement('curve', JXG.Math.Numerics.bezier(p), {strokecolor:'blue', strokeOpacity:0.6, strokeWidth:5});
