Canvas-трансформации доступным языком

new Matrix2d().
	Rotate(angle, rotationPoint).
	FlipY(rotationPoint).
	CreateTransform(context);

function Matrix2d () {
	var _matrix = [[1, 0, 0], [0, 1, 0], [0, 0, 1]];
	
	var CalcOffset = function (matrix) {
		var x = matrix[0][2] * matrix[0][0] + matrix[1][2] * matrix[0][1];
		var y = matrix[0][2] * matrix[1][0] + matrix[1][2] * matrix[1][1];
		
		matrix[0][2] -= x;
		matrix[1][2] -= y;
		
		return matrix;
	}
	
	var Multiply = function (matrix) {
		var mulMatrix = [[0, 0, 0], [0, 0, 0], [0, 0, 0]];
		
		for (var x = 0; x < 3; x++) {
			for (var y = 0; y < 3; y++) {
				var sum = 0;
				
				for (var dim = 0; dim < 3; dim++) {
					sum += _matrix[y][dim] * matrix[dim][x];
				}
				
				mulMatrix[y][x] = sum;
			}
		}
		
		_matrix = mulMatrix;
	}
	
	this.Rotate = function (angle, point) {
		var sin = Math.sin(angle);
		var cos = Math.cos(angle);
		
		Multiply(CalcOffset([
			[cos, -sin, point.x],
			[sin, cos, point.y],
			[0, 0, 1]
		]));
		
		return this;
	}
	
	this.FlipY = function (point) {
		Multiply(CalcOffset([
			[-1, 0, point.x],
			[0, 1, point.y],
			[0, 0, 1]
		]));
		
		return this;
	}
	
	this.FlipX = function (point) {
		Multiply(CalcOffset([
			[1, 0, point.x],
			[0, -1, point.y],
			[0, 0, 1]
		]));
		
		return this;
	}
	
	this.FlipXY = function (point) {
		Multiply(CalcOffset([
			[-1, 0, point.x],
			[0, -1, point.y],
			[0, 0, 1]
		]));
		
		return this;
	}
	
	this.CreateTransform = function (context) {
		context.transform(
			_matrix[0][0],
			_matrix[1][0],
			_matrix[0][1],
			_matrix[1][1],
			_matrix[0][2],
			_matrix[1][2]);
		
		return this;
	}
}