Bezier curves: Difference between revisions
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| A WASSERMANN (talk | contribs) No edit summary | A WASSERMANN (talk | contribs) No edit summary | ||
| Line 36: | Line 36: | ||
|     p.push(brd.createElement('point',[Math.random()*8-4,Math.random()*8-4], |     p.push(brd.createElement('point',[Math.random()*8-4,Math.random()*8-4], | ||
|             {strokeColor:col,fillColor:col}));     // data point |             {strokeColor:col,fillColor:col}));     // data point | ||
|    brd.unsuspendUpdate(); | |||
| }; | |||
| var removeSegment = function() { | |||
|    brd.suspendUpdate(); | |||
|    if (p.length>4) { | |||
|        p.splice(p.length-3,3); | |||
|    } | |||
|     brd.unsuspendUpdate(); |     brd.unsuspendUpdate(); | ||
| }; | }; | ||
Revision as of 06:52, 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});
