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     * Sets the opacity (alpha) of every pixel in an image to a constant value.
031     */
032    public class OpacityFilter extends PointFilter  implements DynFiltering {
033            
034            private int opacity;
035            private int opacity24;
036    
037            /**
038             * Construct an OpacityFilter with 50% opacity.
039             */
040            public OpacityFilter() {
041                    this(0x88);
042            }
043    
044            /**
045             * Construct an OpacityFilter with the given opacity (alpha).
046             * @param opacity the opacity (alpha) in the range 0..255
047             */
048            public OpacityFilter(int opacity) {
049                    setOpacity(opacity);
050            }
051    
052            /**
053             * Set the opacity.
054             * @param opacity the opacity (alpha) in the range 0..255
055         * @see #getOpacity
056             */
057            public void setOpacity(int opacity) {
058                    this.opacity = opacity;
059                    opacity24 = opacity << 24;
060            }
061            
062            /**
063             * Get the opacity setting.
064             * @return the opacity
065         * @see #setOpacity
066             */
067            public int getOpacity() {
068                    return opacity;
069            }
070            
071            public int filterRGB(int x, int y, int rgb) {
072                    if ((rgb & 0xff000000) != 0)
073                            return (rgb & 0xffffff) | opacity24;
074                    return rgb;
075            }
076    
077            public String toString() {
078                    return "Colors/Transparency...";
079            }
080    
081            public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src);
082                    Object o;
083                    if((o=parameters.removeEL(KeyImpl.init("Opacity")))!=null)setOpacity(ImageFilterUtil.toIntValue(o,"Opacity"));
084                    if((o=parameters.removeEL(KeyImpl.init("Dimensions")))!=null){
085                            int[] dim=ImageFilterUtil.toDimensions(o,"Dimensions");
086                            setDimensions(dim[0],dim[1]);
087                    }
088    
089                    // check for arguments not supported
090                    if(parameters.size()>0) {
091                            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 [Opacity, Dimensions]");
092                    }
093    
094                    return filter(src, dst);
095            }
096    }
097