bitmat.js

/*
  Ported to JavaScript by Lazar Laszlo 2011 
  
  lazarsoft@gmail.com, www.lazarsoft.info
  
*/

/*
*
* Copyright 2007 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/


function BitMatrix( width,  height)
{
	if(!height)
		height=width;
	if (width < 1 || height < 1)
	{
		throw "Both dimensions must be greater than 0";
	}
	this.width = width;
	this.height = height;
	var rowSize = width >> 5;
	if ((width & 0x1f) != 0)
	{
		rowSize++;
	}
	this.rowSize = rowSize;
	this.bits = new Array(rowSize * height);
	for(var i=0;i<this.bits.length;i++)
		this.bits[i]=0;
	
	this.__defineGetter__("Width", function()
	{
		return this.width;
	});
	this.__defineGetter__("Height", function()
	{
		return this.height;
	});
	this.__defineGetter__("Dimension", function()
	{
		if (this.width != this.height)
		{
			throw "Can't call getDimension() on a non-square matrix";
		}
		return this.width;
	});
	
	this.get_Renamed=function( x,  y)
		{
			var offset = y * this.rowSize + (x >> 5);
			return ((URShift(this.bits[offset], (x & 0x1f))) & 1) != 0;
		}
	this.set_Renamed=function( x,  y)
		{
			var offset = y * this.rowSize + (x >> 5);
			this.bits[offset] |= 1 << (x & 0x1f);
		}
	this.flip=function( x,  y)
		{
			var offset = y * this.rowSize + (x >> 5);
			this.bits[offset] ^= 1 << (x & 0x1f);
		}
	this.clear=function()
		{
			var max = this.bits.length;
			for (var i = 0; i < max; i++)
			{
				this.bits[i] = 0;
			}
		}
	this.setRegion=function( left,  top,  width,  height)
		{
			if (top < 0 || left < 0)
			{
				throw "Left and top must be nonnegative";
			}
			if (height < 1 || width < 1)
			{
				throw "Height and width must be at least 1";
			}
			var right = left + width;
			var bottom = top + height;
			if (bottom > this.height || right > this.width)
			{
				throw "The region must fit inside the matrix";
			}
			for (var y = top; y < bottom; y++)
			{
				var offset = y * this.rowSize;
				for (var x = left; x < right; x++)
				{
					this.bits[offset + (x >> 5)] |= 1 << (x & 0x1f);
				}
			}
		}
}