directcolormodel.java

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            // overflows nBits, so we need to clamp.
            if (red > ((1<<nBits[0]) - 1)) {
                red = (1<<nBits[0]) - 1;
            }
            if (grn > ((1<<nBits[1]) - 1)) {
                grn = (1<<nBits[1]) - 1;
            }
            if (blu > ((1<<nBits[2]) - 1)) {
                blu = (1<<nBits[2]) - 1;
            }
        }

        intpixel[0] |= (red << maskOffsets[0]) |
                       (grn << maskOffsets[1]) |
                       (blu << maskOffsets[2]);

        switch (transferType) {
            case DataBuffer.TYPE_BYTE: {
               byte bdata[];
               if (pixel == null) {
                   bdata = new byte[1];
               } else {
                   bdata = (byte[])pixel;
               }
               bdata[0] = (byte)(0xff&intpixel[0]);
               return bdata;
            }
            case DataBuffer.TYPE_USHORT:{
               short sdata[];
               if (pixel == null) {
                   sdata = new short[1];
               } else {
                   sdata = (short[])pixel;
               }
               sdata[0] = (short)(intpixel[0]&0xffff);
               return sdata;
            }
            case DataBuffer.TYPE_INT:
               return intpixel;
        }
        throw new UnsupportedOperationException("This method has not been "+
                 "implemented for transferType " + transferType);

    }

    /**
     * Returns an array of unnormalized color/alpha components given a pixel
     * in this <code>ColorModel</code>.  The pixel value is specified as an 
     * <code>int</code>.  If the <code>components</code> array is 
     * <code>null</code>, a new array is allocated.  The
     * <code>components</code> array is returned.  Color/alpha components are
     * stored in the <code>components</code> array starting at 
     * <code>offset</code>, even if the array is allocated by this method.  
     * An <code>ArrayIndexOutOfBoundsException</code> is thrown if the 
     * <code>components</code> array is not <code>null</code> and is not large
     * enough to hold all the color and alpha components, starting at 
     * <code>offset</code>.
     * @param pixel the specified pixel
     * @param components the array to receive the color and alpha
     * components of the specified pixel
     * @param offset the offset into the <code>components</code> array at
     * which to start storing the color and alpha components
     * @return an array containing the color and alpha components of the
     * specified pixel starting at the specified offset.
     */
    final public int[] getComponents(int pixel, int[] components, int offset) {
        if (components == null) {
            components = new int[offset+numComponents];
        }

        for (int i=0; i < numComponents; i++) {
            components[offset+i] = (pixel & maskArray[i]) >>> maskOffsets[i];
        }

        return components;
    }
    
    /**
     * Returns an array of unnormalized color/alpha components given a pixel
     * in this <code>ColorModel</code>.  The pixel value is specified by an 
     * array of data elements of type <code>transferType</code> passed in as 
     * an object reference.  If <code>pixel</code> is not a primitive array
     * of type <code>transferType</code>, a <code>ClassCastException</code>
     * is thrown.  An <code>ArrayIndexOutOfBoundsException</code> is
     * thrown if <code>pixel</code> is not large enough to hold a
     * pixel value for this <code>ColorModel</code>.  If the 
     * <code>components</code> array is <code>null</code>, a new
     * array is allocated.  The <code>components</code> array is returned.
     * Color/alpha components are stored in the <code>components</code> array 
     * starting at <code>offset</code>, even if the array is allocated by 
     * this method.  An <code>ArrayIndexOutOfBoundsException</code>
     * is thrown if the <code>components</code> array is not 
     * <code>null</code> and is not large enough to hold all the color and 
     * alpha components, starting at <code>offset</code>.
     * Since <code>DirectColorModel</code> can be subclassed, subclasses
     * inherit the implementation of this method and if they don't
     * override it then they throw an exception if they use an unsupported
     * <code>transferType</code>.
     * @param pixel the specified pixel
     * @param components the array to receive the color and alpha
     *        components of the specified pixel
     * @param offset the offset into the <code>components</code> array at
     *        which to start storing the color and alpha components
     * @return an array containing the color and alpha components of the
     * specified pixel starting at the specified offset.
     * @exception ClassCastException if <code>pixel</code> 
     *  is not a primitive array of type <code>transferType</code>
     * @exception ArrayIndexOutOfBoundsException if
     *  <code>pixel</code> is not large enough to hold a pixel value
     *  for this <code>ColorModel</code>, or if <code>components</code>
     *  is not <code>null</code> and is not large enough to hold all the
     *  color and alpha components, starting at <code>offset</code>
     * @exception UnsupportedOperationException if this
     *            <code>transferType</code> is not supported by this
     *            color model 
     */
    final public int[] getComponents(Object pixel, int[] components,
                                     int offset) {
        int intpixel=0;
        switch (transferType) {
     	    case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])pixel;
               intpixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])pixel;
               intpixel = sdata[0] & 0xffff;
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])pixel;
               intpixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return getComponents(intpixel, components, offset);
    }
    
    /**
     * Creates a <code>WritableRaster</code> with the specified width and
     * height that has a data layout (<code>SampleModel</code>) compatible 
     * with this <code>ColorModel</code>.  
     * @param w the width to apply to the new <code>WritableRaster</code>
     * @param h the height to apply to the new <code>WritableRaster</code>
     * @return a <code>WritableRaster</code> object with the specified
     * width and height.
     * @throws IllegalArgumentException if <code>w</code> or <code>h</code>
     *         is less than or equal to zero  
     * @see WritableRaster
     * @see SampleModel
     */
    final public WritableRaster createCompatibleWritableRaster (int w,
                                                                int h) {
        if ((w <= 0) || (h <= 0)) {
            throw new IllegalArgumentException("Width (" + w + ") and height (" + h + 
                                               ") cannot be <= 0");
        }
        int[] bandmasks;
        if (supportsAlpha) {
            bandmasks = new int[4];
            bandmasks[3] = alpha_mask;
        }
        else {
            bandmasks = new int[3];
        }
        bandmasks[0] = red_mask;
        bandmasks[1] = green_mask;
        bandmasks[2] = blue_mask;
        
        if (pixel_bits > 16) {
	    return Raster.createPackedRaster(DataBuffer.TYPE_INT,
                                             w,h,bandmasks,null); 
        }
        else if (pixel_bits > 8) {
	    return Raster.createPackedRaster(DataBuffer.TYPE_USHORT,
                                             w,h,bandmasks,null); 
        }
        else {
	    return Raster.createPackedRaster(DataBuffer.TYPE_BYTE,
                                             w,h,bandmasks,null); 
        }
    }

    /**
     * Returns a pixel value represented as an <code>int</code> in this 
     * <code>ColorModel</code>, given an array of unnormalized color/alpha 
     * components.   An <code>ArrayIndexOutOfBoundsException</code> is 
     * thrown if the <code>components</code> array is
     * not large enough to hold all the color and alpha components, starting
     * at <code>offset</code>.
     * @param components an array of unnormalized color and alpha
     * components
     * @param offset the index into <code>components</code> at which to
     * begin retrieving the color and alpha components
     * @return an <code>int</code> pixel value in this
     * <code>ColorModel</code> corresponding to the specified components.  
     * @exception <code>ArrayIndexOutOfBoundsException</code> if
     *  the <code>components</code> array is not large enough to 
     *	hold all of the color and alpha components starting at
     *	<code>offset</code> 
     */
    public int getDataElement(int[] components, int offset) {
        int pixel = 0;
        for (int i=0; i < numComponents; i++) {
            pixel |= ((components[offset+i]<<maskOffsets[i])&maskArray[i]);
        }
        return pixel;
    }
    
    /**
     * Returns a data element array representation of a pixel in this
     * <code>ColorModel</code>, given an array of unnormalized color/alpha 
     * components.
     * This array can then be passed to the <code>setDataElements</code> 
     * method of a <code>WritableRaster</code> object.
     * An <code>ArrayIndexOutOfBoundsException</code> is thrown if the 
     * <code>components</code> array
     * is not large enough to hold all the color and alpha components,
     * starting at offset.  If the <code>obj</code> variable is 
     * <code>null</code>, a new array is allocated.  If <code>obj</code> is 
     * not <code>null</code>, it must be a primitive array
     * of type <code>transferType</code>; otherwise, a 
     * <code>ClassCastException</code> is thrown.
     * An <code>ArrayIndexOutOfBoundsException</code> is thrown if 
     * <code>obj</code> is not large enough to hold a pixel value for this 
     * <code>ColorModel</code>.
     * Since <code>DirectColorModel</code> can be subclassed, subclasses
     * inherit the implementation of this method and if they don't
     * override it then they throw an exception if they use an unsupported
     * <code>transferType</code>.
     * @param components an array of unnormalized color and alpha
     * components
     * @param offset the index into <code>components</code> at which to
     * begin retrieving color and alpha components
     * @param obj the <code>Object</code> representing an array of color
     * and alpha components
     * @return an <code>Object</code> representing an array of color and
     * alpha components.
     * @exception <code>ClassCastException</code> if <code>obj</code>
     *  is not a primitive array of type <code>transferType</code>
     * @exception <code>ArrayIndexOutOfBoundsException</code> if
     *  <code>obj</code> is not large enough to hold a pixel value
     *  for this <code>ColorModel</code> or the <code>components</code>
     *	array is not large enough to hold all of the color and alpha
     *	components starting at <code>offset</code> 
     * @exception UnsupportedOperationException if this
     *            <code>transferType</code> is not supported by this
     *            color model
     * @see WritableRaster#setDataElements
     * @see SampleModel#setDataElements
     */
    public Object getDataElements(int[] components, int offset, Object obj) {
        int pixel = 0;
        for (int i=0; i < numComponents; i++) {
            pixel |= ((components[offset+i]<<maskOffsets[i])&maskArray[i]);
        }
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               if (obj instanceof byte[]) {
                   byte bdata[] = (byte[])obj;
                   bdata[0] = (byte)(pixel&0xff);
                   return bdata;
               } else {
                   byte bdata[] = {(byte)(pixel&0xff)};
                   return bdata;
               }
            case DataBuffer.TYPE_USHORT:
               if (obj instanceof short[]) {
                   short sdata[] = (short[])obj;
                   sdata[0] = (short)(pixel&0xffff);
                   return sdata;
               } else {
                   short sdata[] = {(short)(pixel&0xffff)};
                   return sdata;
               }
            case DataBuffer.TYPE_INT:
               if (obj instanceof int[]) {
                   int idata[] = (int[])obj;
                   idata[0] = pixel;
                   return idata;