Java Raster.getBounds方法代码示例

import java.awt.image.Raster; //导入方法依赖的package包/类
/**
 * Copies an arbitrary rectangular region of the RenderedImage
 * into a caller-supplied WritableRaster.  The region to be
 * computed is determined by clipping the bounds of the supplied
 * WritableRaster against the bounds of the image.  The supplied
 * WritableRaster must have a SampleModel that is compatible with
 * that of the image.
 *
 * <p> If the raster argument is null, the entire image will
 * be copied into a newly-created WritableRaster with a SampleModel
 * that is compatible with that of the image.
 *
 * @param dest a WritableRaster to hold the returned portion of
 *        the image.
 * @return a reference to the supplied WritableRaster, or to a
 *         new WritableRaster if the supplied one was null.
 */
public WritableRaster copyData(WritableRaster dest) {
    // Get the image bounds.
    Rectangle imageBounds = getBounds();

    Rectangle bounds;
    if (dest == null) {
        // Create a WritableRaster for the entire image.
        bounds = imageBounds;
        Point p = new Point(minX, minY);
        SampleModel sm =
            sampleModel.createCompatibleSampleModel(width, height);
        dest = Raster.createWritableRaster(sm, p);
    } else {
        bounds = dest.getBounds();
    }

    // Determine tile limits for the intersection of the prescribed
    // bounds with the image bounds.
    Rectangle xsect = imageBounds.contains(bounds) ?
        bounds : bounds.intersection(imageBounds);
    int startX = XToTileX(xsect.x);
    int startY = YToTileY(xsect.y);
    int endX = XToTileX(xsect.x + xsect.width - 1);
    int endY = YToTileY(xsect.y + xsect.height - 1);

    // Loop over the tiles in the intersection.
    for (int j = startY; j <= endY; j++) {
        for (int i = startX; i <= endX; i++) {
            // Retrieve the tile.
            Raster tile = getTile(i, j);

            // Create a child of the tile for the intersection of
            // the tile bounds and the bounds of the requested area.
            Rectangle tileRect = tile.getBounds();
            Rectangle intersectRect =
                bounds.intersection(tile.getBounds());
            Raster liveRaster = tile.createChild(intersectRect.x,
                                                 intersectRect.y,
                                                 intersectRect.width,
                                                 intersectRect.height,
                                                 intersectRect.x,
                                                 intersectRect.y,
                                                 null);

            // Copy the data from the child.
            dest.setRect(liveRaster);
        }
    }

    return dest;
}