sku-pg
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Skulpt is a Javascript implementation of Python 2.x. Python that runs in your browser!
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HTML
<html>
<!--
Copyright 2007 The Closure Library Authors. All Rights Reserved.
Use of this source code is governed by the Apache License, Version 2.0.
See the COPYING file for details.
-->
<head>
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title>Closure Unit Tests - goog.math.Bezier</title>
<script src="../base.js"></script>
<script>
goog.require('goog.math.Bezier');
goog.require('goog.testing.jsunit');
</script>
</head>
<body>
<script>
function testEquals() {
var input = new goog.math.Bezier(1, 2, 3, 4, 5, 6, 7, 8);
assert(input.equals(input));
}
function testClone() {
var input = new goog.math.Bezier(1, 2, 3, 4, 5, 6, 7, 8);
assertNotEquals('Clone returns a new object', input, input.clone())
assert('Contents of clone match original', input.equals(input.clone()));
}
function testFlip() {
var input = new goog.math.Bezier(1, 1, 2, 2, 3, 3, 4, 4);
var compare = new goog.math.Bezier(4, 4, 3, 3, 2, 2, 1, 1);
var flipped = input.clone();
flipped.flip();
assert('Flipped behaves as expected', compare.equals(flipped));
flipped.flip();
assert('Flipping twice gives original', input.equals(flipped));
}
function testGetPoint() {
var input = new goog.math.Bezier(0, 1, 1, 2, 2, 3, 3, 4);
assert(goog.math.Coordinate.equals(input.getPoint(0),
new goog.math.Coordinate(0, 1)));
assert(goog.math.Coordinate.equals(input.getPoint(1),
new goog.math.Coordinate(3, 4)));
assert(goog.math.Coordinate.equals(input.getPoint(0.5),
new goog.math.Coordinate(1.5, 2.5)));
}
function testSubdivide() {
var input = new goog.math.Bezier(0, 1, 1, 2, 2, 3, 3, 4);
input.subdivide(1/3, 2/3);
assert(goog.math.nearlyEquals(1, input.x0));
assert(goog.math.nearlyEquals(2, input.y0));
assert(goog.math.nearlyEquals(2, input.x3));
assert(goog.math.nearlyEquals(3, input.y3));
}
function testSolvePositionFromXValue() {
var eps = 1e-6;
var bezier = new goog.math.Bezier(0, 0, 0.25, 0.1, 0.25, 1, 1, 1);
var pt = bezier.getPoint(0.5);
assertRoughlyEquals(0.3125, pt.x, eps);
assertRoughlyEquals(0.5375, pt.y, eps);
assertRoughlyEquals(0.321,
bezier.solvePositionFromXValue(bezier.getPoint(0.321).x), eps);
}
function testSolveYValueFromXValue() {
var eps = 1e-6;
// The following example is taken from
// http://www.netzgesta.de/dev/cubic-bezier-timing-function.html.
// The timing values shown in that page are 1 - <value> so the
// bezier curves in this test are constructed with 1 - ctrl points.
// E.g. ctrl points (0, 0, 0.25, 0.1, 0.25, 1, 1, 1) become
// (1, 1, 0.75, 0, 0.75, 0.9, 0, 0) here. Since chanding the order of
// the ctrl points does not affect the shape of the curve, once can also
// have (0, 0, 0.75, 0.9, 0.75, 0, 1, 1).
// netzgesta example.
var bezier = new goog.math.Bezier(1, 1, 0.75, 0.9, 0.75, 0, 0, 0);
assertRoughlyEquals(0.024374631, bezier.solveYValueFromXValue(0.2), eps);
assertRoughlyEquals(0.317459494, bezier.solveYValueFromXValue(0.6), eps);
assertRoughlyEquals(0.905205002, bezier.solveYValueFromXValue(0.9), eps);
// netzgesta example with ctrl points in the reverse order so that 1st and
// last ctrl points are (0, 0) and (1, 1). Note the result is exactly the
// same.
bezier = new goog.math.Bezier(0, 0, 0.75, 0, 0.75, 0.9, 1, 1);
assertRoughlyEquals(0.024374631, bezier.solveYValueFromXValue(0.2), eps);
assertRoughlyEquals(0.317459494, bezier.solveYValueFromXValue(0.6), eps);
assertRoughlyEquals(0.905205002, bezier.solveYValueFromXValue(0.9), eps);
// Ease-out css animation timing in webkit.
bezier = new goog.math.Bezier(0, 0, 0, 0, 0.58, 1, 1, 1);
assertRoughlyEquals(0.308366667, bezier.solveYValueFromXValue(0.2), eps);
assertRoughlyEquals(0.785139061, bezier.solveYValueFromXValue(0.6), eps);
assertRoughlyEquals(0.982973389, bezier.solveYValueFromXValue(0.9), eps);
}
</script>
</body>
</html>