001    /*
002    *
003    
004    Licensed under the Apache License, Version 2.0 (the "License");
005    you may not use this file except in compliance with the License.
006    You may obtain a copy of the License at
007    
008       http://www.apache.org/licenses/LICENSE-2.0
009    
010    Unless required by applicable law or agreed to in writing, software
011    distributed under the License is distributed on an "AS IS" BASIS,
012    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013    See the License for the specific language governing permissions and
014    limitations under the License.
015    */
016    
017    package railo.runtime.img.filter;import java.awt.image.BufferedImage;
018    
019    import railo.runtime.engine.ThreadLocalPageContext;
020    import railo.runtime.exp.FunctionException;
021    import railo.runtime.exp.PageException;
022    import railo.runtime.img.ImageUtil;
023    import railo.runtime.type.KeyImpl;
024    import railo.runtime.type.Struct;
025    import railo.runtime.type.util.CollectionUtil;
026    
027    
028    
029    /**
030     * A Filter to invert the alpha channel of an image. This is really only useful for inverting selections, where we only use the alpha channel.
031     */
032    public class InvertAlphaFilter extends PointFilter  implements DynFiltering {
033    
034            public InvertAlphaFilter() {
035                    canFilterIndexColorModel = true;
036            }
037    
038            public int filterRGB(int x, int y, int rgb) {
039                    return rgb ^ 0xff000000;
040            }
041    
042            public String toString() {
043                    return "Alpha/Invert";
044            }
045            public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src);
046                    Object o;
047                    if((o=parameters.removeEL(KeyImpl.init("Dimensions")))!=null){
048                            int[] dim=ImageFilterUtil.toDimensions(o,"Dimensions");
049                            setDimensions(dim[0],dim[1]);
050                    }
051    
052                    // check for arguments not supported
053                    if(parameters.size()>0) {
054                            throw new FunctionException(ThreadLocalPageContext.get(), "ImageFilter", 3, "parameters", "the parameter"+(parameters.size()>1?"s":"")+" ["+CollectionUtil.getKeyList(parameters,", ")+"] "+(parameters.size()>1?"are":"is")+" not allowed, only the following parameters are supported [Dimensions]");
055                    }
056    
057                    return filter(src, dst);
058            }
059    }