Much smoother freehand paths

git-svn-id: http://svg-edit.googlecode.com/svn/trunk@1348 eee81c28-f429-11dd-99c0-75d572ba1ddd
master
Jeff Schiller 2010-02-06 00:35:32 +00:00
parent 6980e8b0de
commit 1b2bb9c412
1 changed files with 63 additions and 1 deletions

View File

@ -2301,6 +2301,51 @@ function BatchCommand(text) {
return (m.a == 1 && m.b == 0 && m.c == 0 && m.d == 1 && m.e == 0 && m.f == 0);
}
// expects three points to be sent, each point must have an x,y field
// returns an array of two points that are the smoothed
this.smoothControlPoints = function(ct1, ct2, pt) {
// each point must not be the origin
var x1 = ct1.x - pt.x,
y1 = ct1.y - pt.y,
x2 = ct2.x - pt.x,
y2 = ct2.y - pt.y;
if ( (x1 != 0 || y1 != 0) && (x2 != 0 || y2 != 0) ) {
var anglea = Math.atan2(y1,x1),
angleb = Math.atan2(y2,x2),
r1 = Math.sqrt(x1*x1+y1*y1),
r2 = Math.sqrt(x2*x2+y2*y2),
nct1 = svgroot.createSVGPoint(),
nct2 = svgroot.createSVGPoint();
if (anglea < 0) { anglea += 2*Math.PI; }
if (angleb < 0) { angleb += 2*Math.PI; }
var angleBetween = Math.abs(anglea - angleb),
angleDiff = Math.abs(Math.PI - angleBetween)/2;
var new_anglea, new_angleb;
if (anglea - angleb > 0) {
new_anglea = angleBetween < Math.PI ? (anglea + angleDiff) : (anglea - angleDiff);
new_angleb = angleBetween < Math.PI ? (angleb - angleDiff) : (angleb + angleDiff);
}
else {
new_anglea = angleBetween < Math.PI ? (anglea - angleDiff) : (anglea + angleDiff);
new_angleb = angleBetween < Math.PI ? (angleb + angleDiff) : (angleb - angleDiff);
}
// rotate the points
nct1.x = r1 * Math.cos(new_anglea) + pt.x;
nct1.y = r1 * Math.sin(new_anglea) + pt.y;
nct2.x = r2 * Math.cos(new_angleb) + pt.x;
nct2.y = r2 * Math.sin(new_angleb) + pt.y;
return [nct1, nct2];
}
return undefined;
};
var smoothControlPoints = this.smoothControlPoints;
// matrixMultiply() is provided because WebKit didn't implement multiply() correctly
// on the SVGMatrix interface. See https://bugs.webkit.org/show_bug.cgi?id=16062
// This function tries to return a SVGMatrix that is the multiplication m1*m2.
@ -3523,7 +3568,24 @@ function BatchCommand(text) {
// if the previous segment had a control point, we want to smooth out
// the control points on both sides
if (prevCtlPt) {
// TODO: fancy processing here :)
var newpts = smoothControlPoints( prevCtlPt, ct1, curpos );
if (newpts.length == 2) {
// set previous control point 2
// console.log("prev ctl point 2 = " + prevCtlPt.x + "," + prevCtlPt.y);
// console.log(d[d.length-1]);
// console.log(newpts);
var prevArr = d[d.length-1].split(',');
// console.log("prevArr[2]=" + prevArr[2]);
// console.log(newpts[0].x);
prevArr[2] = newpts[0].x;
prevArr[3] = newpts[0].y;
// console.log(prevArr);
// TODO: do I need to update d or is the array a reference?
// console.log(d[d.length-1]);
d[d.length-1] = prevArr.join(',');
// console.log(d[d.length-1]);
ct1 = newpts[1];
}
}
d.push([ct1.x,ct1.y,ct2.x,ct2.y,end.x,end.y].join(','));