/**
 * <dl>
 * <dt> class JavaPixel
 * <dd> a class representing a pixel in a picture
 * </dl>
 * @author Mark Guzdial
 * @version 2
 *
 * modified by Alyce Brady, 17 October 2005
 *   in an attempt to speed up calls to getPixel and setColor;
 *   added the getColor, setColor, setColorFrom, and setAlpha methods
 */
public class JavaPixel {
	JavaPicture my_pic;
	public int x;
	public int y;
	// private int red;
	// private int green;
	// private int blue;
	// private int alpha;

	// int value;
        java.awt.Color pxColor;

        /** 
         * 
         * @param pic the JavaPicture object for each the JavaPixel is a pixel for
         * @param px the x coordinate of the pixel in pic
         * @param py the y coordinate of the pixel in pic
         */
	public JavaPixel ( JavaPicture pic, int px, int py )
	{
	   my_pic = pic;
	   x = px;
	   y = py;

           pxColor = new java.awt.Color(my_pic.getBasicPixel(x, y));
	   // value = my_pic.getBasicPixel(x,y);
	   // red = (value >> 16) & 0xff;
	   // green = (value >>  8) & 0xff;
	   // blue = (value      ) & 0xff;
	   // alpha = (value >> 24) & 0xff;
	 }

	 // these are integers [0,255]
         /**
          * Returns the red value of the pixel.
          *
          * @return the red value in an integer
          */
	 public int getRed()
	 {
	 	// return red;
                // return (value >> 16) & 0xff;
                return pxColor.getRed();
	 }

         /**
          * Returns the green value of the pixel.
          *
          * @return the green value in an integer
          */
	 public int getGreen()
	 {
		// return green;
                // return (value >> 8) & 0xff;
                return pxColor.getGreen();
	 }

         /**
          * Returns the blue value of the pixel.
          *
          * @return the blue value in an integer
          */
	 public int getBlue()
	 {
		// return blue;
                // return (value      ) & 0xff;
                return pxColor.getBlue();
	 }

         /** Returns the alpha value of the pixel.
          *
          * @return the alpha value in an integer
          */
	 public int getAlpha()
	 {
	 	// return alpha;
                // return (value >> 24) & 0xff;
                return pxColor.getAlpha();
	 }

         /**
          * Returns the color of this pixel.
          *
          * @return the color
          */
	 public java.awt.Color getColor()
	 {
                return pxColor;
	 }

	 // The set versions
         /**
          * actually sets the integer (or basic) value of the pixel once the separate
          * red, green, blue and alpha values are set
          *
          */
         /* Commented out by Alyce Brady; replaced with methods below.
	 public void setPixel()
	 {
	 	value = (alpha << 24) + (red << 16) + (green << 8) + blue;
	 	my_pic.setBasicPixel(x,y,value);
	 }
         */

         /**
          * Sets the color value of the pixel from the given parameters.
          *
          * Added by Alyce Brady.
          */
         public void setColor(int red, int green, int blue, int alpha)
         {
	 	// value = (alpha << 24) + (red << 16) + (green << 8) + blue;
                setColor(new java.awt.Color(red, green, blue, alpha));
         }

         /**
          * Sets the color value of the pixel from the
          * given color value.
          *
          * Added by Alyce Brady.
          */
         public void setColor(java.awt.Color c)
         {
	 	// value = c.getRGB();
	 	pxColor = c;
	 	my_pic.setBasicPixel(x,y,c.getRGB());
         }

         /**
          * Sets the color value of this pixel from the color value
          * of <code>otherPixel</code>.
          *   @arg otherPixel  a pixel that may be in the same picture
          *                     or a different picture from this pixel
          *
          * Added by Alyce Brady.
          */
         public void setColorFrom(JavaPixel otherPixel)
         {
                setColor(otherPixel.getColor());
         }

         /**
          * Sets the red value of the pixel.
          *
          * @param nuRed the red value as an integer
          */
	 public void setRed(int nuRed)
	 {
	 	// red = (int) (nuRed & 0xff);
	 	// this.setPixel();
	 	// int red = (int) (nuRed & 0xff);
	 	// this.setPixel(red, getGreen(), getBlue(), getAlpha());
                setColor(nuRed, pxColor.getGreen(),
                         pxColor.getBlue(), pxColor.getAlpha());
	 }

         /**
          * Sets the green value of the pixel.
          *
          * @param nuGreen the green value as an integer
          */
	 public void setGreen(int nuGreen)
	 {
	 	// green = (int) (nuGreen & 0xff);
	 	// this.setPixel();
	 	// int green = (int) (nuGreen & 0xff);
	 	// this.setPixel(getRed(), green, getBlue(), getAlpha());
                setColor(pxColor.getRed(), nuGreen,
                         pxColor.getBlue(), pxColor.getAlpha());
	 }

         /**
          * Sets the blue value of the pixel.
          *
          * @param nuBlue the blue value as an integer
          */
	 public void setBlue(int nuBlue)
	 {
	 	// blue = (int) (nuBlue & 0xff);
	 	// this.setPixel();
	 	// int blue = (int) (nuBlue & 0xff);
	 	// this.setPixel(getRed(), getGreen(), blue, getAlpha());
                setColor(pxColor.getRed(), pxColor.getGreen(),
                         nuBlue, pxColor.getAlpha());
	 }

         /**
          * Sets the alpha (transparency) value of the pixel.
          *
          * @param nuAlpha the alpha value as an integer
          */
	 public void setAlpha(int nuAlpha)
	 {
                setColor(pxColor.getRed(), pxColor.getGreen(),
                         pxColor.getBlue(), nuAlpha);
	 }

}