blob: 8b2c6f9edb3d3b34babc455edd40b10d09672918 [file] [log] [blame]
/*
* Copyright (C) 2013 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
WI.Point = class Point
{
constructor(x, y)
{
this.x = x || 0;
this.y = y || 0;
}
// Static
static fromEvent(event)
{
return new WI.Point(event.pageX, event.pageY);
}
static fromEventInElement(event, element)
{
let rect = element.getBoundingClientRect();
return new WI.Point(event.pageX - rect.x, event.pageY - rect.y);
}
// Public
toString()
{
return "WI.Point[" + this.x + "," + this.y + "]";
}
copy()
{
return new WI.Point(this.x, this.y);
}
equals(anotherPoint)
{
return this.x === anotherPoint.x && this.y === anotherPoint.y;
}
distance(anotherPoint)
{
let dx = anotherPoint.x - this.x;
let dy = anotherPoint.y - this.y;
return Math.sqrt((dx * dx) + (dy * dy));
}
};
WI.Size = class Size
{
constructor(width, height)
{
this.width = width || 0;
this.height = height || 0;
}
// Public
toString()
{
return "WI.Size[" + this.width + "," + this.height + "]";
}
copy()
{
return new WI.Size(this.width, this.height);
}
equals(anotherSize)
{
return this.width === anotherSize.width && this.height === anotherSize.height;
}
};
WI.Size.ZERO_SIZE = new WI.Size(0, 0);
WI.Rect = class Rect
{
constructor(x, y, width, height)
{
this.origin = new WI.Point(x || 0, y || 0);
this.size = new WI.Size(width || 0, height || 0);
}
// Static
static rectFromClientRect(clientRect)
{
return new WI.Rect(clientRect.left, clientRect.top, clientRect.width, clientRect.height);
}
static unionOfRects(rects)
{
var union = rects[0];
for (var i = 1; i < rects.length; ++i)
union = union.unionWithRect(rects[i]);
return union;
}
// Public
toString()
{
return "WI.Rect[" + [this.origin.x, this.origin.y, this.size.width, this.size.height].join(", ") + "]";
}
copy()
{
return new WI.Rect(this.origin.x, this.origin.y, this.size.width, this.size.height);
}
equals(anotherRect)
{
return this.origin.equals(anotherRect.origin) && this.size.equals(anotherRect.size);
}
inset(insets)
{
return new WI.Rect(
this.origin.x + insets.left,
this.origin.y + insets.top,
this.size.width - insets.left - insets.right,
this.size.height - insets.top - insets.bottom
);
}
pad(padding)
{
return new WI.Rect(
this.origin.x - padding,
this.origin.y - padding,
this.size.width + padding * 2,
this.size.height + padding * 2
);
}
minX()
{
return this.origin.x;
}
minY()
{
return this.origin.y;
}
midX()
{
return this.origin.x + (this.size.width / 2);
}
midY()
{
return this.origin.y + (this.size.height / 2);
}
maxX()
{
return this.origin.x + this.size.width;
}
maxY()
{
return this.origin.y + this.size.height;
}
intersectionWithRect(rect)
{
var x1 = Math.max(this.minX(), rect.minX());
var x2 = Math.min(this.maxX(), rect.maxX());
if (x1 > x2)
return WI.Rect.ZERO_RECT;
var intersection = new WI.Rect;
intersection.origin.x = x1;
intersection.size.width = x2 - x1;
var y1 = Math.max(this.minY(), rect.minY());
var y2 = Math.min(this.maxY(), rect.maxY());
if (y1 > y2)
return WI.Rect.ZERO_RECT;
intersection.origin.y = y1;
intersection.size.height = y2 - y1;
return intersection;
}
unionWithRect(rect)
{
var x = Math.min(this.minX(), rect.minX());
var y = Math.min(this.minY(), rect.minY());
var width = Math.max(this.maxX(), rect.maxX()) - x;
var height = Math.max(this.maxY(), rect.maxY()) - y;
return new WI.Rect(x, y, width, height);
}
round()
{
return new WI.Rect(
Math.floor(this.origin.x),
Math.floor(this.origin.y),
Math.ceil(this.size.width),
Math.ceil(this.size.height)
);
}
};
WI.Rect.ZERO_RECT = new WI.Rect(0, 0, 0, 0);
WI.EdgeInsets = class EdgeInsets
{
constructor(top, right, bottom, left)
{
console.assert(arguments.length === 1 || arguments.length === 4);
if (arguments.length === 1) {
this.top = top;
this.right = top;
this.bottom = top;
this.left = top;
} else if (arguments.length === 4) {
this.top = top;
this.right = right;
this.bottom = bottom;
this.left = left;
}
}
// Public
equals(anotherInset)
{
return this.top === anotherInset.top && this.right === anotherInset.right
&& this.bottom === anotherInset.bottom && this.left === anotherInset.left;
}
copy()
{
return new WI.EdgeInsets(this.top, this.right, this.bottom, this.left);
}
};
WI.RectEdge = {
MIN_X: 0,
MIN_Y: 1,
MAX_X: 2,
MAX_Y: 3
};
WI.Quad = class Quad
{
constructor(quad)
{
this.points = [
new WI.Point(quad[0], quad[1]), // top left
new WI.Point(quad[2], quad[3]), // top right
new WI.Point(quad[4], quad[5]), // bottom right
new WI.Point(quad[6], quad[7]) // bottom left
];
this.width = Math.round(Math.sqrt(Math.pow(quad[0] - quad[2], 2) + Math.pow(quad[1] - quad[3], 2)));
this.height = Math.round(Math.sqrt(Math.pow(quad[0] - quad[6], 2) + Math.pow(quad[1] - quad[7], 2)));
}
// Import / Export
static fromJSON(json)
{
return new WI.Quad(json);
}
toJSON()
{
return this.toProtocol();
}
// Public
toProtocol()
{
return [
this.points[0].x, this.points[0].y,
this.points[1].x, this.points[1].y,
this.points[2].x, this.points[2].y,
this.points[3].x, this.points[3].y
];
}
};
WI.Polygon = class Polygon
{
constructor(points)
{
this.points = points;
}
// Public
bounds()
{
var minX = Number.MAX_VALUE;
var minY = Number.MAX_VALUE;
var maxX = -Number.MAX_VALUE;
var maxY = -Number.MAX_VALUE;
for (var point of this.points) {
minX = Math.min(minX, point.x);
maxX = Math.max(maxX, point.x);
minY = Math.min(minY, point.y);
maxY = Math.max(maxY, point.y);
}
return new WI.Rect(minX, minY, maxX - minX, maxY - minY);
}
};
WI.CubicBezier = class CubicBezier
{
constructor(x1, y1, x2, y2)
{
this._inPoint = new WI.Point(x1, y1);
this._outPoint = new WI.Point(x2, y2);
// Calculate the polynomial coefficients, implicit first and last control points are (0,0) and (1,1).
this._curveInfo = {
x: {c: 3.0 * x1},
y: {c: 3.0 * y1}
};
this._curveInfo.x.b = 3.0 * (x2 - x1) - this._curveInfo.x.c;
this._curveInfo.x.a = 1.0 - this._curveInfo.x.c - this._curveInfo.x.b;
this._curveInfo.y.b = 3.0 * (y2 - y1) - this._curveInfo.y.c;
this._curveInfo.y.a = 1.0 - this._curveInfo.y.c - this._curveInfo.y.b;
}
// Static
static fromCoordinates(coordinates)
{
if (!coordinates || coordinates.length < 4)
return null;
coordinates = coordinates.map(Number);
if (coordinates.includes(NaN))
return null;
return new WI.CubicBezier(coordinates[0], coordinates[1], coordinates[2], coordinates[3]);
}
static fromString(text)
{
if (!text || !text.length)
return null;
var trimmedText = text.toLowerCase().replace(/\s/g, "");
if (!trimmedText.length)
return null;
if (Object.keys(WI.CubicBezier.keywordValues).includes(trimmedText))
return WI.CubicBezier.fromCoordinates(WI.CubicBezier.keywordValues[trimmedText]);
var matches = trimmedText.match(/^cubic-bezier\(([-\d.]+),([-\d.]+),([-\d.]+),([-\d.]+)\)$/);
if (!matches)
return null;
matches.splice(0, 1);
return WI.CubicBezier.fromCoordinates(matches);
}
// Public
get inPoint()
{
return this._inPoint;
}
get outPoint()
{
return this._outPoint;
}
copy()
{
return new WI.CubicBezier(this._inPoint.x, this._inPoint.y, this._outPoint.x, this._outPoint.y);
}
toString()
{
var values = [this._inPoint.x, this._inPoint.y, this._outPoint.x, this._outPoint.y];
for (var key in WI.CubicBezier.keywordValues) {
if (Array.shallowEqual(WI.CubicBezier.keywordValues[key], values))
return key;
}
return "cubic-bezier(" + values.join(", ") + ")";
}
solve(x, epsilon)
{
return this._sampleCurveY(this._solveCurveX(x, epsilon));
}
// Private
_sampleCurveX(t)
{
// `ax t^3 + bx t^2 + cx t' expanded using Horner's rule.
return ((this._curveInfo.x.a * t + this._curveInfo.x.b) * t + this._curveInfo.x.c) * t;
}
_sampleCurveY(t)
{
return ((this._curveInfo.y.a * t + this._curveInfo.y.b) * t + this._curveInfo.y.c) * t;
}
_sampleCurveDerivativeX(t)
{
return (3.0 * this._curveInfo.x.a * t + 2.0 * this._curveInfo.x.b) * t + this._curveInfo.x.c;
}
// Given an x value, find a parametric value it came from.
_solveCurveX(x, epsilon)
{
var t0, t1, t2, x2, d2, i;
// First try a few iterations of Newton's method -- normally very fast.
for (t2 = x, i = 0; i < 8; i++) {
x2 = this._sampleCurveX(t2) - x;
if (Math.abs(x2) < epsilon)
return t2;
d2 = this._sampleCurveDerivativeX(t2);
if (Math.abs(d2) < 1e-6)
break;
t2 = t2 - x2 / d2;
}
// Fall back to the bisection method for reliability.
t0 = 0.0;
t1 = 1.0;
t2 = x;
if (t2 < t0)
return t0;
if (t2 > t1)
return t1;
while (t0 < t1) {
x2 = this._sampleCurveX(t2);
if (Math.abs(x2 - x) < epsilon)
return t2;
if (x > x2)
t0 = t2;
else
t1 = t2;
t2 = (t1 - t0) * 0.5 + t0;
}
// Failure.
return t2;
}
};
WI.CubicBezier.keywordValues = {
"ease": [0.25, 0.1, 0.25, 1],
"ease-in": [0.42, 0, 1, 1],
"ease-out": [0, 0, 0.58, 1],
"ease-in-out": [0.42, 0, 0.58, 1],
"linear": [0, 0, 1, 1]
};
WI.Spring = class Spring
{
constructor(mass, stiffness, damping, initialVelocity)
{
this.mass = Math.max(1, mass);
this.stiffness = Math.max(1, stiffness);
this.damping = Math.max(0, damping);
this.initialVelocity = initialVelocity;
}
// Static
static fromValues(values)
{
if (!values || values.length < 4)
return null;
values = values.map(Number);
if (values.includes(NaN))
return null;
return new WI.Spring(...values);
}
static fromString(text)
{
if (!text || !text.length)
return null;
let trimmedText = text.toLowerCase().trim();
if (!trimmedText.length)
return null;
let matches = trimmedText.match(/^spring\(([\d.]+)\s+([\d.]+)\s+([\d.]+)\s+([-\d.]+)\)$/);
if (!matches)
return null;
return WI.Spring.fromValues(matches.slice(1));
}
// Public
copy()
{
return new WI.Spring(this.mass, this.stiffness, this.damping, this.initialVelocity);
}
toString()
{
return `spring(${this.mass} ${this.stiffness} ${this.damping} ${this.initialVelocity})`;
}
solve(t)
{
let w0 = Math.sqrt(this.stiffness / this.mass);
let zeta = this.damping / (2 * Math.sqrt(this.stiffness * this.mass));
let wd = 0;
let A = 1;
let B = -this.initialVelocity + w0;
if (zeta < 1) {
// Under-damped.
wd = w0 * Math.sqrt(1 - zeta * zeta);
A = 1;
B = (zeta * w0 + -this.initialVelocity) / wd;
}
if (zeta < 1) // Under-damped
t = Math.exp(-t * zeta * w0) * (A * Math.cos(wd * t) + B * Math.sin(wd * t));
else // Critically damped (ignoring over-damped case).
t = (A + B * t) * Math.exp(-t * w0);
return 1 - t; // Map range from [1..0] to [0..1].
}
calculateDuration(epsilon)
{
epsilon = epsilon || 0.0001;
let t = 0;
let current = 0;
let minimum = Number.POSITIVE_INFINITY;
while (current >= epsilon || minimum >= epsilon) {
current = Math.abs(1 - this.solve(t)); // Undo the range mapping
if (minimum < epsilon && current >= epsilon)
minimum = Number.POSITIVE_INFINITY; // Spring reversed direction
else if (current < minimum)
minimum = current;
t += 0.1;
}
return t;
}
};