kity/src/graphic/sweep.js

Kity Graphic Library

define(function(require, exports, module) {
    var Point = require('./point');

    return require('../core/class').createClass('Sweep', {

        base: require('./path'),

        constructor: function(sectionArray, angle, angleOffset) {
            this.callBase();
            this.sectionArray = sectionArray || [];
            this.angle = angle || 0;
            this.angleOffset = angleOffset || 0;
            this.draw();
        },

        getSectionArray: function() {
            return this.sectionArray;
        },

        setSectionArray: function(value) {
            this.sectionArray = value;
            return this.draw();
        },

        getAngle: function() {
            return this.angle;
        },

        setAngle: function(value) {
            this.angle = value;
            return this.draw();
        },

        getAngleOffset: function() {
            return this.angleOffset;
        },

        setAngleOffset: function(value) {
            this.angleOffset = value;
            return this.draw();
        },

        draw: function() {
            var sectionArray = this.sectionArray,
                i;
            for (i = 0; i < sectionArray.length; i += 2) {
                this.drawSection(sectionArray[i], sectionArray[i + 1]);
            }
            return this;
        },

        drawSection: function(from, to) {
            var angleLength = this.angle && (this.angle % 360 ? this.angle % 360 : 360),
                angleStart = this.angleOffset,
                angleHalf = angleStart + angleLength / 2,
                angleEnd = angleStart + angleLength,
                sweepFlag = angleLength < 0 ? 0 : 1,
                drawer = this.getDrawer();

            drawer.redraw();

            if (angleLength === 0) {
                drawer.done();
                return;
            }

            drawer.moveTo(Point.fromPolar(from, angleStart));

            drawer.lineTo(Point.fromPolar(to, angleStart));

            if (to) {
                drawer.carcTo(to, 0, sweepFlag, Point.fromPolar(to, angleHalf));
                drawer.carcTo(to, 0, sweepFlag, Point.fromPolar(to, angleEnd));
            }

            drawer.lineTo(Point.fromPolar(from, angleEnd));

            if (from) {
                drawer.carcTo(from, 0, sweepFlag, Point.fromPolar(from, angleHalf));
                drawer.carcTo(from, 0, sweepFlag, Point.fromPolar(from, angleStart));
            }

            drawer.close();
            drawer.done();
        }
    });
});