colormodel.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 443 行 · 第 1/2 页

    }

    /**
     * Returns the number of bits per pixel described by this ColorModel.
     */
    public int getPixelSize() {
        return pixel_bits;
    }

    /**
     * The subclass must provide a function which provides the red
     * color compoment for the specified pixel.
     * @return		The red color component ranging from 0 to 255
     */
    public abstract int getRed(int pixel);

    /**
     * The subclass must provide a function which provides the green
     * color compoment for the specified pixel.
     * @return		The green color component ranging from 0 to 255
     */
    public abstract int getGreen(int pixel);

    /**
     * The subclass must provide a function which provides the blue
     * color compoment for the specified pixel.
     * @return		The blue color component ranging from 0 to 255
     */
    public abstract int getBlue(int pixel);

    /**
     * The subclass must provide a function which provides the alpha
     * color compoment for the specified pixel.
     * @return		The alpha transparency value ranging from 0 to 255
     */
    public abstract int getAlpha(int pixel);

    /**
     * Returns the color of the pixel in the default RGB color model.
     * @see ColorModel#getRGBdefault
     */
    public int getRGB(int pixel) {
        return (getAlpha(pixel) << 24)
            | (getRed(pixel) << 16)
            | (getGreen(pixel) << 8)
            | (getBlue(pixel) << 0);
    }

    /**
     * Tests if the specified <code>Object</code> is an instance of
     * <code>ColorModel</code> and if it equals this
     * <code>ColorModel</code>.
     * @param obj the <code>Object</code> to test for equality
     * @return <code>true</code> if the specified <code>Object</code>
     * is an instance of <code>ColorModel</code> and equals this
     * <code>ColorModel</code>; <code>false</code> otherwise.
     */
    public boolean equals(Object obj) {
        if (!(obj instanceof ColorModel)) {
            return false;
        }
        ColorModel cm = (ColorModel) obj;
        if (this == cm) {
            return true;
        }
        if (supportsAlpha != cm.hasAlpha() ||
            isAlphaPremultiplied != cm.isAlphaPremultiplied() ||
            transparency != cm.getTransparency() ||
            pixel_bits != cm.getPixelSize()) {
            return false;
        }
        return true;
    }

    /**
     * Disposes of system resources associated with this
     * <code>ColorModel</code> once this <code>ColorModel</code> is no
     * longer referenced.
     */
    public void finalize() {
    }

    /**
     * Returns the hash code for this ColorModel.
     *
     * @return    a hash code for this ColorModel.
     */
    public int hashCode() {
        int result = 0;
        result = (supportsAlpha ? 2 : 3) +
                (isAlphaPremultiplied ? 4 : 5) +
                pixel_bits * 6 +
                transparency * 7;
        return result;
    }

    /**
     * Returns the <code>ColorSpace</code> associated with this
     * <code>ColorModel</code>.
     * @return the <code>ColorSpace</code> of this
     * <code>ColorModel</code>.
     */
    final public ColorSpace getColorSpace() {
        return colorSpace;
    }

    /**
     * Returns the transparency.  Returns either OPAQUE, BITMASK,
     * or TRANSLUCENT.
     * @return the transparency of this <code>ColorModel</code>.
     * @see Transparency#OPAQUE
     * @see Transparency#BITMASK
     * @see Transparency#TRANSLUCENT
     */
    public int getTransparency() {
        return transparency;
    }
        
    /**
     * Returns the number of bits for the specified color/alpha component.
     * Color components are indexed in the order specified by the 
     * <code>ColorSpace</code>.  Typically, this order reflects the name
     * of the color space type. For example, for TYPE_RGB, index 0
     * corresponds to red, index 1 to green, and index 2
     * to blue.  If this <code>ColorModel</code> supports alpha, the alpha
     * component corresponds to the index following the last color
     * component.
     * @param componentIdx the index of the color/alpha component
     * @return the number of bits for the color/alpha component at the
     *		specified index.
     * @throws ArrayIndexOutOfBoundsException if <code>componentIdx</code> 
     *         is greater than the number of components or
     *         less than zero
     * @throws NullPointerException if the number of bits array is 
     *         <code>null</code>
     */
    public int getComponentSize(int componentIdx) {
        // NOTE
        if (nBits == null) {
            throw new NullPointerException("Number of bits array is null.");
        }
        return nBits[componentIdx];
    }

    /**
     * Returns an array of the number of bits per color/alpha component.  
     * The array contains the color components in the order specified by the
     * <code>ColorSpace</code>, followed by the alpha component, if
     * present.
     * @return an array of the number of bits per color/alpha component
     */
    public int[] getComponentSize() {
        if (nBits != null) {
            return (int[]) nBits.clone();
        }
        return null;
    }        

    /**
     * Returns the number of components, including alpha, in this
     * <code>ColorModel</code>.  This is equal to the number of color
     * components, optionally plus one, if there is an alpha component.
     * @return the number of components in this <code>ColorModel</code>
     */
    public int getNumComponents() {
        return numComponents;
    }

    /**
     * Returns the number of color components in this
     * <code>ColorModel</code>.
     * This is the number of components returned by
     * {@link ColorSpace#getNumComponents}.
     * @return the number of color components in this
     * <code>ColorModel</code>.
     * @see ColorSpace#getNumComponents
     */
    public int getNumColorComponents() {
        return numColorComponents;
    }    

    /**
     * Returns the transfer type of this <code>ColorModel</code>.
     * The transfer type is the type of primitive array used to represent
     * pixel values as arrays.
     * @return the transfer type.
     */
    public final int getTransferType() {
        return transferType;
    }    

    static final int getDefaultTransferType(int pixel_bits) {
        if (pixel_bits <= 8) {
            return DataBuffer.TYPE_BYTE;
        } else if (pixel_bits <= 16) {
            return DataBuffer.TYPE_USHORT;
        } else if (pixel_bits <= 32) {
            return DataBuffer.TYPE_INT;
        } else {
            return DataBuffer.TYPE_UNDEFINED;
        }
    }     

    /**
     * Returns the <code>String</code> representation of the contents of
     * this <code>ColorModel</code>object.
     * @return a <code>String</code> representing the contents of this
     * <code>ColorModel</code> object.
     */
    public String toString() {
        return new String("ColorModel: #pixelBits = " + pixel_bits
                + " numComponents = " + numComponents
                + " color space = " + colorSpace
                + " transparency = " + transparency
                + " has alpha = " + supportsAlpha
                + " isAlphaPre = " + isAlphaPremultiplied
            );
    }

}