////////////////////////////////////////////////////////////////////////////////
//
//  NOTEFLIGHT LLC
//  Copyright 2009 Noteflight LLC
//	This filter was created from GainFilter.as by Momo the Monster of MMM Labs
// 
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
//  THE SOFTWARE.
//
////////////////////////////////////////////////////////////////////////////////


package com.noteflight.standingwave2.filters
{
    import com.noteflight.standingwave2.elements.IAudioSource;
    
    /**
     * PanFilter applies a fixed pan factor to the underlying source.
     */
    public class PanFilter extends AbstractFilter
    {
        /** The pan factor applied. */
        public var pan:Number;
		
		/** Variables to hold per-channel transforms */
		private var _leftFactor:Number;
		private var _rightFactor:Number;
        
        /**
         * Create a new PanFilter. 
         * @param source the underlying audio source
         * @param pan the pan factor, between -1  for hard left and 1 for hard right
         */
        public function PanFilter(source:IAudioSource, pan:Number)
        {
            super(source);
            this.pan = pan;
        }
                
        override protected function transformChannel(data:Vector.<Number>, channel:Number, start:Number, numFrames:Number):void
        {
			if (pan > 0){
				_rightFactor = pan;
				_leftFactor = 1-pan;
			} else {
				_rightFactor = 1-Math.abs(pan);
				_leftFactor = Math.abs(pan);
			}//end if
			
            for (var i:Number = 0; i < numFrames; i++)
            {
				switch(channel)
				{
					case 0:
						data[i] *= _leftFactor;
						break;
					
					case 1:
						data[i] *= _rightFactor;
						break;
					
				}//end case
            }//end for
        }//end function transformChannel

        override public function clone():IAudioSource
        {
            return new PanFilter(source.clone(), pan);
        }
    }
}