Bezier curves: Difference between revisions
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A WASSERMANN (talk | contribs) No edit summary |
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var col = 'red'; | var col = 'red'; | ||
p.push(brd.createElement('point',[2,1],{strokeColor:col,fillColor:col,name:p.length+1})); // data point | p.push(brd.createElement('point',[2,1],{strokeColor:col,fillColor:col,name:(p.length+1)})); // data point | ||
col = 'blue'; | col = 'blue'; | ||
p.push(brd.createElement('point',[0.75,2.5],{strokeColor:col,fillColor:col,name:p.length+1})); // control point | p.push(brd.createElement('point',[0.75,2.5],{strokeColor:col,fillColor:col,name:(p.length+1)})); // control point | ||
p.push(brd.createElement('point',[-0.3,0.3],{strokeColor:col,fillColor:col,name:p.length+1})); // control point | p.push(brd.createElement('point',[-0.3,0.3],{strokeColor:col,fillColor:col,name:(p.length+1)})); // control point | ||
col = 'red'; | col = 'red'; | ||
p.push(brd.createElement('point',[-3,1],{strokeColor:col,fillColor:col,name:p.length+1})); // data point | p.push(brd.createElement('point',[-3,1],{strokeColor:col,fillColor:col,name:(p.length+1)})); // data point | ||
col = 'blue'; | col = 'blue'; | ||
p.push(brd.createElement('point',[-0.75,-2.5],{strokeColor:col,fillColor:col,name:p.length+1})); // control point | p.push(brd.createElement('point',[-0.75,-2.5],{strokeColor:col,fillColor:col,name:(p.length+1)})); // control point | ||
p.push(brd.createElement('point',[1.5,-2.8],{strokeColor:col,fillColor:col,name:p.length+1})); // control point | p.push(brd.createElement('point',[1.5,-2.8],{strokeColor:col,fillColor:col,name:(p.length+1)})); // control point | ||
col = 'red'; | col = 'red'; | ||
p.push(brd.createElement('point',[2,-0.5],{strokeColor:col,fillColor:col,name:p.length+1})); // data point | p.push(brd.createElement('point',[2,-0.5],{strokeColor:col,fillColor:col,name:(p.length+)1})); // data point | ||
var c = brd.createElement('curve', JXG.Math.Numerics.bezier(p), {strokecolor:'blue', strokeOpacity:0.6, strokeWidth:5}); | var c = brd.createElement('curve', JXG.Math.Numerics.bezier(p), | ||
{strokecolor:'blue', strokeOpacity:0.6, strokeWidth:5}); | |||
var addSegment = function() { | var addSegment = function() { | ||
| Line 30: | Line 31: | ||
col = 'blue'; | col = 'blue'; | ||
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,name:p.length+1})); // control point | {strokeColor:col,fillColor:col,name:(p.length+1)})); // control point | ||
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,name:p.length+1})); // control point | {strokeColor:col,fillColor:col,name:(p.length+1)})); // control point | ||
col = 'red'; | col = 'red'; | ||
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,name:p.length+1})); // data point | {strokeColor:col,fillColor:col,name:(p.length+1)})); // data point | ||
brd.unsuspendUpdate(); | brd.unsuspendUpdate(); | ||
}; | }; | ||
Revision as of 07:15, 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});
