directcolormodel.java

JAVA基本类源代码,大家可以学习学习!

    final public int getAlphaMask() {
        if (supportsAlpha) {
            return maskArray[3];
        } else {
            return 0;
        }
    }


    /*
     * Given an int pixel in this ColorModel's ColorSpace, converts
     * it to the default sRGB ColorSpace and returns the R, G, and B
     * components as float values between 0.0 and 1.0.
     */
    private float[] getDefaultRGBComponents(int pixel) {
        int components[] = getComponents(pixel, null, 0);
        float norm[] = getNormalizedComponents(components, 0, null, 0);
        // Note that getNormalizedComponents returns non-premultiplied values
        return colorSpace.toRGB(norm);
    }


    private int getsRGBComponentFromsRGB(int pixel, int idx) {
	int c = ((pixel & maskArray[idx]) >>> maskOffsets[idx]);
        if (isAlphaPremultiplied) {
            int a = ((pixel & maskArray[3]) >>> maskOffsets[3]);
            c = (a == 0) ? 0 :
                         (int) (((c * scaleFactors[idx]) * 255.0f /
                                 (a * scaleFactors[3])) + 0.5f);
        } else if (scaleFactors[idx] != 1.0f) {
	    c = (int) ((c * scaleFactors[idx]) + 0.5f);
        }
	return c;
    }


    private int getsRGBComponentFromLinearRGB(int pixel, int idx) {
	int c = ((pixel & maskArray[idx]) >>> maskOffsets[idx]);
        if (isAlphaPremultiplied) {
            float factor = (float) ((1 << lRGBprecision) - 1);
            int a = ((pixel & maskArray[3]) >>> maskOffsets[3]);
            c = (a == 0) ? 0 :
                         (int) (((c * scaleFactors[idx]) * factor /
                                 (a * scaleFactors[3])) + 0.5f);
        } else if (nBits[idx] != lRGBprecision) {
            if (lRGBprecision == 16) {
                c = (int) ((c * scaleFactors[idx] * 257.0f) + 0.5f);
            } else {
	        c = (int) ((c * scaleFactors[idx]) + 0.5f);
            }
        }
        // now range of c is 0-255 or 0-65535, depending on lRGBprecision
	return tosRGB8LUT[c] & 0xff;
    }


    /**
     * Returns the red color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB <code>ColorSpace</code>, sRGB.  A 
     * color conversion is done if necessary.  The pixel value is specified 
     * as an <code>int</code>.
     * The returned value is a non pre-multiplied value.  Thus, if the
     * alpha is premultiplied, this method divides it out before returning
     * the value.  If the alpha value is 0, for example, the red value 
     * is 0.
     * @param pixel the specified pixel
     * @return the red color component for the specified pixel, from 
     *         0 to 255 in the sRGB <code>ColorSpace</code>.
     */
    final public int getRed(int pixel) {
        if (is_sRGB) {
            return getsRGBComponentFromsRGB(pixel, 0);
        } else if (is_LinearRGB) {
            return getsRGBComponentFromLinearRGB(pixel, 0);
        }
        float rgb[] = getDefaultRGBComponents(pixel);
        return (int) (rgb[0] * 255.0f + 0.5f);
    }

    /**
     * Returns the green color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB <code>ColorSpace</code>, sRGB.  A 
     * color conversion is done if necessary.  The pixel value is specified
     * as an <code>int</code>.
     * The returned value is a non pre-multiplied value.  Thus, if the
     * alpha is premultiplied, this method divides it out before returning
     * the value.  If the alpha value is 0, for example, the green value
     * is 0.
     * @param pixel the specified pixel
     * @return the green color component for the specified pixel, from 
     *         0 to 255 in the sRGB <code>ColorSpace</code>.
     */
    final public int getGreen(int pixel) {
        if (is_sRGB) {
            return getsRGBComponentFromsRGB(pixel, 1);
        } else if (is_LinearRGB) {
            return getsRGBComponentFromLinearRGB(pixel, 1);
        }
        float rgb[] = getDefaultRGBComponents(pixel);
        return (int) (rgb[1] * 255.0f + 0.5f);
    }

    /**
     * Returns the blue color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB <code>ColorSpace</code>, sRGB.  A 
     * color conversion is done if necessary.  The pixel value is specified
     * as an <code>int</code>.
     * The returned value is a non pre-multiplied value.  Thus, if the
     * alpha is premultiplied, this method divides it out before returning
     * the value.  If the alpha value is 0, for example, the blue value
     * is 0.
     * @param pixel the specified pixel
     * @return the blue color component for the specified pixel, from 
     *         0 to 255 in the sRGB <code>ColorSpace</code>.
     */
    final public int getBlue(int pixel) {
        if (is_sRGB) {
            return getsRGBComponentFromsRGB(pixel, 2);
        } else if (is_LinearRGB) {
            return getsRGBComponentFromLinearRGB(pixel, 2);
        }
        float rgb[] = getDefaultRGBComponents(pixel);
        return (int) (rgb[2] * 255.0f + 0.5f);
    }

    /**
     * Returns the alpha component for the specified pixel, scaled
     * from 0 to 255.  The pixel value is specified as an <code>int</code>.
     * @param pixel the specified pixel
     * @return the value of the alpha component of <code>pixel</code>
     *         from 0 to 255.    
     */
    final public int getAlpha(int pixel) {
	if (!supportsAlpha) return 255;
	int a = ((pixel & maskArray[3]) >>> maskOffsets[3]);
	if (scaleFactors[3] != 1.0f) {
	    a = (int)(a * scaleFactors[3] + 0.5f);
	}
	return a;
    }

    /**
     * Returns the color/alpha components of the pixel in the default
     * RGB color model format.  A color conversion is done if necessary.
     * The pixel value is specified as an <code>int</code>.
     * The returned value is in a non pre-multiplied format.  Thus, if
     * the alpha is premultiplied, this method divides it out of the
     * color components.  If the alpha value is 0, for example, the color 
     * values are each 0.
     * @param pixel the specified pixel
     * @return the RGB value of the color/alpha components of the specified
     *         pixel.
     * @see ColorModel#getRGBdefault
     */
    final public int getRGB(int pixel) {
        if (is_sRGB || is_LinearRGB) {
	    return (getAlpha(pixel) << 24)
	        | (getRed(pixel) << 16)
	        | (getGreen(pixel) << 8)
	        | (getBlue(pixel) << 0);
        }
        float rgb[] = getDefaultRGBComponents(pixel);
        return (getAlpha(pixel) << 24)
            | (((int) (rgb[0] * 255.0f + 0.5f)) << 16)
            | (((int) (rgb[1] * 255.0f + 0.5f)) << 8)
            | (((int) (rgb[2] * 255.0f + 0.5f)) << 0);
    }
    
    /**
     * Returns the red color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB <code>ColorSpace</code>, sRGB.  A 
     * color conversion is done if necessary.  The pixel value is specified
     * by an array of data elements of type <code>transferType</code> passed 
     * in as an object reference.
     * The returned value is a non pre-multiplied value.  Thus, if the
     * alpha is premultiplied, this method divides it out before returning
     * the value.  If the alpha value is 0, for example, the red value 
     * is 0.
     * If <code>inData</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>inData</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>.
     * An <code>UnsupportedOperationException</code> is thrown if this
     * <code>transferType</code> is not supported by this 
     * <code>ColorModel</code>.
     * @param inData the array containing the pixel value
     * @return the value of the red component of the specified pixel.
     * @throws ArrayIndexOutOfBoundsException if <code>inData</code> is not
     *         large enough to hold a pixel value for this color model
     * @throws ClassCastException if <code>inData</code> is not a 
     *         primitive array of type <code>transferType</code>
     * @throws UnsupportedOperationException if this <code>transferType</code>
     *         is not supported by this color model
     */
    public int getRed(Object inData) {
        int pixel=0;
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])inData;
               pixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])inData;
               pixel = sdata[0] & 0xffff;
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])inData;
               pixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return getRed(pixel);
    }
   

    /**
     * Returns the green color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB <code>ColorSpace</code>, sRGB.  A 
     * color conversion is done if necessary.  The pixel value is specified
     * by an array of data elements of type <code>transferType</code> passed 
     * in as an object reference.
     * The returned value is a non pre-multiplied value.  Thus, if the
     * alpha is premultiplied, this method divides it out before returning
     * the value.  If the alpha value is 0, for example, the green value 
     * is 0.  If <code>inData</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>inData</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>.
     * An <code>UnsupportedOperationException</code> is
     * thrown if this <code>transferType</code> is not supported by this 
     * <code>ColorModel</code>.
     * @param inData the array containing the pixel value
     * @return the value of the green component of the specified pixel.
     * @throws ArrayIndexOutOfBoundsException if <code>inData</code> is not
     *         large enough to hold a pixel value for this color model
     * @throws ClassCastException if <code>inData</code> is not a 
     *         primitive array of type <code>transferType</code>
     * @throws UnsupportedOperationException if this <code>transferType</code>
     *         is not supported by this color model
     */
    public int getGreen(Object inData) {
        int pixel=0;
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])inData;
               pixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])inData;
               pixel = sdata[0] & 0xffff;
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])inData;
               pixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return getGreen(pixel);
    }
   

    /**
     * Returns the blue color component for the specified pixel, scaled
     * from 0 to 255 in the default RGB <code>ColorSpace</code>, sRGB.  A 
     * color conversion is done if necessary.  The pixel value is specified
     * by an array of data elements of type <code>transferType</code> passed 
     * in as an object reference.