paper.js/src/path/CompoundPath.js
2013-10-20 01:54:53 +02:00

303 lines
8.4 KiB
JavaScript

/*
* Paper.js - The Swiss Army Knife of Vector Graphics Scripting.
* http://paperjs.org/
*
* Copyright (c) 2011 - 2013, Juerg Lehni & Jonathan Puckey
* http://lehni.org/ & http://jonathanpuckey.com/
*
* Distributed under the MIT license. See LICENSE file for details.
*
* All rights reserved.
*/
/**
* @name CompoundPath
*
* @class A compound path contains two or more paths, holes are drawn
* where the paths overlap. All the paths in a compound path take on the
* style of the backmost path and can be accessed through its
* {@link Item#children} list.
*
* @extends PathItem
*/
var CompoundPath = PathItem.extend(/** @lends CompoundPath# */{
_class: 'CompoundPath',
_serializeFields: {
children: []
},
/**
* Creates a new compound path item and places it in the active layer.
*
* @param {Path[]} [paths] the paths to place within the compound path.
*
* @example {@paperscript}
* // Create a circle shaped path with a hole in it:
* var circle = new Path.Circle({
* center: new Point(50, 50),
* radius: 30
* });
*
* var innerCircle = new Path.Circle({
* center: new Point(50, 50),
* radius: 10
* });
*
* var compoundPath = new CompoundPath([circle, innerCircle]);
* compoundPath.fillColor = 'red';
*
* // Move the inner circle 5pt to the right:
* compoundPath.children[1].position.x += 5;
*/
initialize: function CompoundPath(arg) {
// CompoundPath has children and supports named children.
this._children = [];
this._namedChildren = {};
if (!this._initialize(arg))
this.addChildren(Array.isArray(arg) ? arg : arguments);
},
insertChildren: function insertChildren(index, items, _preserve) {
// Pass on 'path' for _type, to make sure that only paths are added as
// children.
items = insertChildren.base.call(this, index, items, _preserve, 'path');
// All children except for the bottom one (first one in list) are set
// to anti-clockwise orientation, so that they appear as holes, but
// only if their orientation was not already specified before
// (= _clockwise is defined).
for (var i = 0, l = !_preserve && items && items.length; i < l; i++) {
var item = items[i];
if (item._clockwise === undefined)
item.setClockwise(item._index === 0);
}
return items;
},
/**
* Reverses the orientation of all nested paths.
*/
reverse: function() {
var children = this._children;
for (var i = 0, l = children.length; i < l; i++)
children[i].reverse();
},
smooth: function() {
for (var i = 0, l = this._children.length; i < l; i++)
this._children[i].smooth();
},
/**
* Specifies whether the compound path is oriented clock-wise.
*
* @type Boolean
* @bean
*/
isClockwise: function() {
var child = this.getFirstChild();
return child && child.isClockwise();
},
setClockwise: function(clockwise) {
if (this.isClockwise() != !!clockwise)
this.reverse();
},
/**
* The first Segment contained within the path.
*
* @type Segment
* @bean
*/
getFirstSegment: function() {
var first = this.getFirstChild();
return first && first.getFirstSegment();
},
/**
* The last Segment contained within the path.
*
* @type Segment
* @bean
*/
getLastSegment: function() {
var last = this.getLastChild();
return last && last.getLastSegment();
},
/**
* All the curves contained within the compound-path, from all its child
* {@link Path} items.
*
* @type Curve[]
* @bean
*/
getCurves: function() {
var children = this._children,
curves = [];
for (var i = 0, l = children.length; i < l; i++)
curves = curves.concat(children[i].getCurves());
return curves;
},
/**
* The first Curve contained within the path.
*
* @type Curve
* @bean
*/
getFirstCurve: function() {
var first = this.getFirstChild();
return first && first.getFirstCurve();
},
/**
* The last Curve contained within the path.
*
* @type Curve
* @bean
*/
getLastCurve: function() {
var last = this.getLastChild();
return last && last.getFirstCurve();
},
/**
* The area of the path in square points. Self-intersecting paths can
* contain sub-areas that cancel each other out.
*
* @type Number
* @bean
*/
getArea: function() {
var children = this._children,
area = 0;
for (var i = 0, l = children.length; i < l; i++)
area += children[i].getArea();
return area;
},
getPathData: function(/* precision */) {
var children = this._children,
paths = [];
for (var i = 0, l = children.length; i < l; i++)
paths.push(children[i].getPathData(arguments[0]));
return paths.join(' ');
},
/**
* A private method to help with both #contains() and #_hitTest().
* Instead of simply returning a boolean, it returns a children of all the
* children that contain the point. This is required by _hitTest(), and
* Item#contains() is prepared for such a result.
*/
_contains: function(point) {
/*#*/ if (options.nativeContains) {
// To compare with native canvas approach:
var ctx = CanvasProvider.getContext(1, 1),
children = this._children,
param = Base.merge({ compound: true });
// Return early if the compound path doesn't have any children:
if (children.length === 0)
return false;
ctx.beginPath();
for (var i = 0, l = children.length; i < l; i++)
children[i]._draw(ctx, param);
var res = ctx.isPointInPath(point.x, point.y, this.getWindingRule());
CanvasProvider.release(ctx);
return res;
/*#*/ } else { // !options.nativeContains
// Compound paths are a little complex: In order to determine whether a
// point is inside a path or not due to the winding rule, we need to
// check all the children and count how many intersect. If it's an odd
// number, the point is inside the path. Once we know it's inside the
// path, _hitTest also needs access to the first intersecting element,
// for the HitResult, so we return it here.
var children = this._children,
winding = 0;
for (var i = 0, l = children.length; i < l; i++)
winding += children[i]._getWinding(point);
return !!(this.getWindingRule() === 'evenodd' ? winding & 1 : winding);
/*#*/ } // !options.nativeContains
},
_hitTest : function _hitTest(point, options) {
// Do not test children for fill, since a compound path forms one shape.
// options.compoundChildren allows to specifically do so, see below.
var res = _hitTest.base.call(this, point,
Base.merge(options, { fill: false }));
if (!res) {
// If asked to query all children seperately, perform the same loop
// as Item#hitTest() now on the compound children.
if (options.compoundChildren) {
var children = this._children;
for (var i = children.length - 1; i >= 0 && !res; i--)
res = children[i]._hitTest(point, options);
} else if (options.fill && this.hasFill()
&& this._contains(point)) {
res = new HitResult('fill', this);
}
}
return res;
},
_draw: function(ctx, param) {
var children = this._children,
style = this._style;
// Return early if the compound path doesn't have any children:
if (children.length === 0)
return;
ctx.beginPath();
param = param.extend({ compound: true });
for (var i = 0, l = children.length; i < l; i++)
children[i].draw(ctx, param);
if (!param.clip) {
this._setStyles(ctx);
if (style.getFillColor())
ctx.fill(style.getWindingRule());
if (style.getStrokeColor())
ctx.stroke();
}
}
}, new function() { // Injection scope for PostScript-like drawing functions
/**
* Helper method that returns the current path and checks if a moveTo()
* command is required first.
*/
function getCurrentPath(that) {
if (!that._children.length)
throw new Error('Use a moveTo() command first');
return that._children[that._children.length - 1];
}
var fields = {
// Note: Documentation for these methods is found in PathItem, as they
// are considered abstract methods of PathItem and need to be defined in
// all implementing classes.
moveTo: function(/* point */) {
var path = new Path();
this.addChild(path);
path.moveTo.apply(path, arguments);
},
moveBy: function(/* point */) {
this.moveTo(getCurrentPath(this).getLastSegment()._point.add(
Point.read(arguments)));
},
closePath: function() {
getCurrentPath(this).closePath();
}
};
// Redirect all other drawing commands to the current path
Base.each(['lineTo', 'cubicCurveTo', 'quadraticCurveTo', 'curveTo',
'arcTo', 'lineBy', 'curveBy', 'arcBy'], function(key) {
fields[key] = function() {
var path = getCurrentPath(this);
path[key].apply(path, arguments);
};
});
return fields;
});