scratchfoundation/paper.js
1
0
Fork 0
mirror of https://github.com/scratchfoundation/paper.js.git synced 2025-01-07 13:22:07 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

Further simplifications of path fitter code.

Browse source
This commit is contained in:
Jürg Lehni 2011-06-05 23:14:28 +01:00
parent 3a4af3f854
commit 2fe21586df
1 changed files with 8 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

20
src/path/PathFitter.js
View file

@ -30,7 +30,6 @@ var PathFitter = Base.extend({
} }
} }
this.error = error; this.error = error;
this.iterationError = error * error;
}, },
fit: function() { fit: function() {
@ -57,24 +56,24 @@ var PathFitter = Base.extend({
} }
// Parameterize points, and attempt to fit curve // Parameterize points, and attempt to fit curve
var uPrime = this.chordLengthParameterize(first, last), var uPrime = this.chordLengthParameterize(first, last),
prevMaxError = this.iterationError, maxError = Math.max(this.error, this.error * this.error),
error, error,
split; split;
// Try 4 iterations // Try 4 iterations
for (var i = 0; i < 4; i++) { for (var i = 0; i <= 4; i++) {
var curve = this.generateBezier(first, last, uPrime, tan1, tan2); var curve = this.generateBezier(first, last, uPrime, tan1, tan2);
// Find max deviation of points to fitted curve // Find max deviation of points to fitted curve
var max = this.findMaxError(first, last, curve, uPrime); var max = this.findMaxError(first, last, curve, uPrime);
if (max.error < this.error) { if (max.error < this.error) {
this.addCurve(curve); this.addCurve(curve);
return; return;
} }
split = max.index; split = max.index;
// If error not too large, try some reparameterization and iteration // If error not too large, try reparameterization and iteration
if (max.error >= this.iterationError || max.error >= prevMaxError) if (max.error >= maxError)
break; break;
uPrime = this.reparameterize(first, last, uPrime, curve); this.reparameterize(first, last, uPrime, curve);
prevMaxError = max.error; maxError = max.error;
} }
// Fitting failed -- split at max error point and fit recursively // Fitting failed -- split at max error point and fit recursively
var V1 = this.points[split - 1].subtract(this.points[split]), var V1 = this.points[split - 1].subtract(this.points[split]),
@ -168,12 +167,9 @@ var PathFitter = Base.extend({
// Given set of points and their parameterization, try to find // Given set of points and their parameterization, try to find
// a better parameterization. // a better parameterization.
reparameterize: function(first, last, u, curve) { reparameterize: function(first, last, u, curve) {
var uPrime = [];
for (var i = first; i <= last; i++) { for (var i = first; i <= last; i++) {
uPrime[i - first] = this.findRoot(curve, this.points[i], u[i - first] = this.findRoot(curve, this.points[i], u[i - first]);
u[i - first]);
} }
return uPrime;
}, },
// Use Newton-Raphson iteration to find better root. // Use Newton-Raphson iteration to find better root.