pattern.js

(function (global) {
	"use strict";
	function Stitch(x, y, flags, color) {
		this.flags = flags;
		this.x = x;
		this.y = y;
		this.color = color;
	}

	function Color(r, g, b, description) {
		this.r = r;
		this.g = g;
		this.b = b;
		this.description = description;
	}

	var stitchTypes = {
			normal: 0,
			jump: 1,
			trim: 2,
			stop: 4,
			end: 8
		};

	function Pattern() {
		this.colors = [];
		this.stitches = [];
        this.hoop = {};
		this.lastX = 0;
		this.lastY = 0;
		this.top = 0;
		this.bottom = 0;
		this.left = 0;
		this.right = 0;
		this.currentColorIndex = 0;
	}

	Pattern.prototype.addColorRgb = function (r, g, b, description) {
		this.colors[this.colors.length] = new Color(r, g, b, description);
	};

	Pattern.prototype.addColor = function (color) {
		this.colors[this.colors.length] = color;
	};

	Pattern.prototype.addStitchAbs = function (x, y, flags, isAutoColorIndex) {
		if ((flags & stitchTypes.end) === stitchTypes.end) {
			this.calculateBoundingBox();
			this.fixColorCount();
		}
		if (((flags & stitchTypes.stop) === stitchTypes.stop) && this.stitches.length === 0) {
			return;
		}
		if (((flags & stitchTypes.stop) === stitchTypes.stop) && isAutoColorIndex) {
			this.currentColorIndex += 1;
		}
		this.stitches[this.stitches.length] = new Stitch(x, y, flags, this.currentColorIndex);
	};

	Pattern.prototype.addStitchRel = function (dx, dy, flags, isAutoColorIndex) {
		if (this.stitches.length !== 0) {
			var nx = this.lastX + dx,
				ny = this.lastY + dy;
			this.lastX = nx;
			this.lastY = ny;
			this.addStitchAbs(nx, ny, flags, isAutoColorIndex);
		} else {
			this.addStitchAbs(dx, dy, flags, isAutoColorIndex);
		}
	};

	Pattern.prototype.calculateBoundingBox = function () {
		var i = 0,
			stitchCount = this.stitches.length,
			pt;
		if (stitchCount === 0) {
			this.bottom = 1;
			this.right = 1;
			return;
		}
		this.left = 99999;
		this.top = 99999;
		this.right = -99999;
		this.bottom = -99999;

		for (i = 0; i < stitchCount; i += 1) {
			pt = this.stitches[i];
			if (!(pt.flags & stitchTypes.trim)) {
				this.left = this.left < pt.x ? this.left : pt.x;
				this.top = this.top < pt.y ? this.top : pt.y;
				this.right = this.right > pt.x ? this.right : pt.x;
				this.bottom = this.bottom > pt.y ? this.bottom : pt.y;
			}
		}
	};

	Pattern.prototype.moveToPositive = function () {
		var i = 0,
			stitchCount = this.stitches.length;
		for (i = 0; i < stitchCount; i += 1) {
			this.stitches[i].x -= this.left;
			this.stitches[i].y -= this.top;
		}
		this.right -= this.left;
		this.left = 0;
		this.bottom -= this.top;
		this.top = 0;
	};

	Pattern.prototype.invertPatternVertical = function () {
		var i = 0,
			temp = -this.top,
			stitchCount = this.stitches.length;
		for (i = 0; i < stitchCount; i += 1) {
			this.stitches[i].y = -this.stitches[i].y;
		}
		this.top = -this.bottom;
		this.bottom = temp;
	};

	Pattern.prototype.addColorRandom = function () {
		this.colors[this.colors.length] = new Color(Math.round(Math.random() * 256), Math.round(Math.random() * 256), Math.round(Math.random() * 256), "random");
	};

	Pattern.prototype.fixColorCount = function () {
		var maxColorIndex = 0,
			stitchCount = this.stitches.length,
			i;
		for (i = 0; i < stitchCount; i += 1) {
			maxColorIndex = Math.max(maxColorIndex, this.stitches[i].color);
		}
		while (this.colors.length <= maxColorIndex) {
			this.addColorRandom();
		}
        this.colors.splice(maxColorIndex + 1, this.colors.length - maxColorIndex - 1);
	};
	
	Pattern.prototype.drawShape = function(canvas) {
		canvas.width = this.right;
		canvas.height = this.bottom;
		if (canvas.getContext) {
			var ctx = canvas.getContext('2d');
			ctx.beginPath();
			var color = this.colors[this.stitches[0].color];
			ctx.strokeStyle = "rgb(" + color.r + "," + color.g + "," + color.b + ")";
			for(var i = 0; i < this.stitches.length; i++)
			{
				var currentStitch = this.stitches[i];
				if (currentStitch.flags === stitchTypes.jump || currentStitch.flags === stitchTypes.trim || currentStitch.flags === stitchTypes.stop) {
					ctx.stroke();
					var color = this.colors[currentStitch.color];
					ctx.beginPath();
					ctx.strokeStyle = "rgb(" + color.r + "," + color.g + "," + color.b + ")";
					ctx.moveTo(currentStitch.x, currentStitch.y);
				}
				ctx.lineTo(currentStitch.x, currentStitch.y);
			}
			ctx.stroke(); 
		} else {
			global.alert('You need Safari or Firefox 1.5+ to see this demo.');
		}
	}

	global.Color = Color.prototype.constructor;
	global.Pattern = Pattern.prototype.constructor;
	global.stitchTypes = stitchTypes;

}(this));