BitMap同时绘制Matrix和ColorMatrix

/**     * Returns an immutable bitmap from subset of the source bitmap,     * transformed by the optional matrix. The new bitmap may be the     * same object as source, or a copy may have been made. It is     * initialized with the same density as the original bitmap.     *      * If the source bitmap is immutable and the requested subset is the     * same as the source bitmap itself, then the source bitmap is     * returned and no new bitmap is created.     *     * @param source   The bitmap we are subsetting     * @param x        The x coordinate of the first pixel in source     * @param y        The y coordinate of the first pixel in source     * @param width    The number of pixels in each row     * @param height   The number of rows     * @param m        Optional matrix to be applied to the pixels     * @param cm   Color matrix to be applied to the pixels     * @param filter   true if the source should be filtered.     *                   Only applies if the matrix contains more than just     *                   translation.     * @return A bitmap that represents the specified subset of source     * @throws IllegalArgumentException if the x, y, width, height values are     *         outside of the dimensions of the source bitmap, or width is <= 0,     *         or height is <= 0     */    public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height,            Matrix m,ColorMatrix cm, boolean filter) {        checkXYSign(x, y);        checkWidthHeight(width, height);        if (x + width > source.getWidth()) {            throw new IllegalArgumentException("x + width must be <= bitmap.width()");        }        if (y + height > source.getHeight()) {            throw new IllegalArgumentException("y + height must be <= bitmap.height()");        }        if (!source.isMutable() && x == 0 && y == 0 && width == source.getWidth() &&                height == source.getHeight() && (m == null || m.isIdentity())) {            return source;        }        int neww = width;        int newh = height;        Canvas canvas = new Canvas();        Bitmap bitmap;        Paint paint;        Rect srcR = new Rect(x, y, x + width, y + height);        RectF dstR = new RectF(0, 0, width, height);        Config newConfig = Config.ARGB_8888;        final Config config = source.getConfig();        // GIF files generate null configs, assume ARGB_8888        if (config != null) {            switch (config) {                case RGB_565:                    newConfig = Config.RGB_565;                    break;                case ALPHA_8:                    newConfig = Config.ALPHA_8;                    break;                //noinspection deprecation                case ARGB_4444:                case ARGB_8888:                default:                    newConfig = Config.ARGB_8888;                    break;            }        }        if (m == null || m.isIdentity()) {            bitmap = Bitmap.createBitmap(neww, newh, newConfig);            paint = null;   // not needed        } else {            final boolean transformed = !m.rectStaysRect();            RectF deviceR = new RectF();            m.mapRect(deviceR, dstR);            neww = Math.round(deviceR.width());            newh = Math.round(deviceR.height());            bitmap = Bitmap.createBitmap(neww, newh, transformed ? Config.ARGB_8888 : newConfig);            canvas.translate(-deviceR.left, -deviceR.top);            canvas.concat(m);            paint = new Paint();            paint.setColorFilter(new ColorMatrixColorFilter(cm));            paint.setFilterBitmap(filter);            if (transformed) {                paint.setAntiAlias(true);            }        }        // The new bitmap was created from a known bitmap source so assume that        // they use the same density        bitmap.setDensity(source.getDensity());        bitmap.setHasAlpha(source.hasAlpha());        bitmap.setPremultiplied(source.isPremultiplied());        canvas.setBitmap(bitmap);        canvas.drawBitmap(source, srcR, dstR, paint);        canvas.setBitmap(null);        return bitmap;    }        /**     * Common code for checking that x and y are >= 0     *     * @param x x coordinate to ensure is >= 0     * @param y y coordinate to ensure is >= 0     */    private static void checkXYSign(int x, int y) {        if (x < 0) {            throw new IllegalArgumentException("x must be >= 0");        }        if (y < 0) {            throw new IllegalArgumentException("y must be >= 0");        }    }    /**     * Common code for checking that width and height are > 0     *     * @param width  width to ensure is > 0     * @param height height to ensure is > 0     */    private static void checkWidthHeight(int width, int height) {        if (width <= 0) {            throw new IllegalArgumentException("width must be > 0");        }        if (height <= 0) {            throw new IllegalArgumentException("height must be > 0");        }    }