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.Point;
018    import java.awt.image.BufferedImage;
019    
020    import railo.runtime.engine.ThreadLocalPageContext;
021    import railo.runtime.exp.FunctionException;
022    import railo.runtime.exp.PageException;
023    import railo.runtime.img.ImageUtil;
024    import railo.runtime.type.KeyImpl;
025    import railo.runtime.type.List;
026    import railo.runtime.type.Struct;
027    
028    /**
029     * A class which warps an image using a field Warp algorithm.
030     */
031    public class FieldWarpFilter extends TransformFilter  implements DynFiltering {
032    
033            public static class Line {
034                    public int x1, y1, x2, y2;
035                    public int dx, dy;
036                    public float length, lengthSquared;
037                    
038                    public Line(int x1, int y1, int x2, int y2) {
039                            this.x1 = x1;
040                            this.y1 = y1;
041                            this.x2 = x2;
042                            this.y2 = y2;
043                    }
044                    
045                    public void setup() {
046                            dx = x2-x1;
047                            dy = y2-y1;
048                            lengthSquared = dx*dx + dy*dy;
049                            length = (float)Math.sqrt(lengthSquared);
050                    }
051            }
052    
053            private float amount = 1.0f;
054            private float power = 1.0f;
055            private float strength = 2.0f;
056            private Line[] inLines;
057            private Line[] outLines;
058            private Line[] intermediateLines;
059            private float width, height;
060    
061            public FieldWarpFilter() {
062            }
063    
064            /**
065             * Set the amount of warp.
066             * @param amount the amount
067         * @min-value 0
068         * @max-value 1
069         * @see #getAmount
070             */
071            public void setAmount(float amount) {
072                    this.amount = amount;
073            }
074            
075            /**
076             * Get the amount of warp.
077             * @return the amount
078         * @see #setAmount
079             */
080            public float getAmount() {
081                    return amount;
082            }
083            
084            public void setPower(float power) {
085                    this.power = power;
086            }
087            
088            public float getPower() {
089                    return power;
090            }
091            
092            public void setStrength(float strength) {
093                    this.strength = strength;
094            }
095            
096            public float getStrength() {
097                    return strength;
098            }
099            
100            public void setInLines( Line[] inLines ) {
101                    this.inLines = inLines;
102            }
103            
104            public Line[] getInLines() {
105                    return inLines;
106            }
107            
108            public void setOutLines( Line[] outLines ) {
109                    this.outLines = outLines;
110            }
111            
112            public Line[] getOutLines() {
113                    return outLines;
114            }
115            
116            protected void transform(int x, int y, Point out) {
117            }
118    
119            protected void transformInverse(int x, int y, float[] out) {
120                    float u = 0, v = 0;
121                    float fraction = 0;
122                    float distance;
123                    float fdist;
124                    float weight;
125                    float a = 0.001f;
126                    float b = 1.5f*strength + 0.5f;
127                    float p = power;
128    
129                    float totalWeight = 0.0f;
130                    float sumX = 0.0f;
131                    float sumY = 0.0f;
132    
133                    for (int line = 0; line < inLines.length; line++) {
134                            Line l1 = inLines[line];
135                            Line l = intermediateLines[line];
136                            float dx = x - l.x1;
137                            float dy = y - l.y1;
138    
139                            fraction = (dx * l.dx + dy * l.dy) / l.lengthSquared;
140                            fdist = (dy * l.dx - dx * l.dy) / l.length;
141                            if (fraction <= 0)
142                                    distance = (float)Math.sqrt(dx*dx + dy*dy);
143                            else if (fraction >= 1) {
144                                    dx = x - l.x2;
145                                    dy = y - l.y2;
146                                    distance = (float)Math.sqrt(dx*dx + dy*dy);
147                            } else if (fdist >= 0)
148                                    distance = fdist;
149                            else
150                                    distance = -fdist;
151                            u = l1.x1 + fraction * l1.dx - fdist * l1.dy / l1.length;
152                            v = l1.y1 + fraction * l1.dy + fdist * l1.dx / l1.length;
153    
154                            weight = (float)Math.pow(Math.pow(l.length, p) / (a + distance), b);
155    
156                            sumX += (u - x) * weight;
157                            sumY += (v - y) * weight;
158    //if (x % 10 == 0&&y == 20)System.out.println("distance="+distance+" weight="+weight+" sumX="+sumX+" sumY="+sumY+" u="+u+" v="+v);
159                            totalWeight += weight;
160                    }
161    
162    //              out[0] = ImageMath.clamp(x + sumX / totalWeight + 0.5f, 0, width-1);
163    //              out[1] = ImageMath.clamp(y + sumY / totalWeight + 0.5f, 0, height-1);
164                    out[0] = x + sumX / totalWeight + 0.5f;
165                    out[1] = y + sumY / totalWeight + 0.5f;
166            }
167    
168        public BufferedImage filter( BufferedImage src, BufferedImage dst ) {
169                    this.width = width;
170                    this.height = height;
171                    if ( inLines != null && outLines != null ) {
172                            intermediateLines = new Line[inLines.length];
173                            for (int line = 0; line < inLines.length; line++) {
174                                    Line l = intermediateLines[line] = new Line(
175                                            ImageMath.lerp(amount, inLines[line].x1, outLines[line].x1),
176                                            ImageMath.lerp(amount, inLines[line].y1, outLines[line].y1),
177                                            ImageMath.lerp(amount, inLines[line].x2, outLines[line].x2),
178                                            ImageMath.lerp(amount, inLines[line].y2, outLines[line].y2)
179                                    );
180                                    l.setup();
181                                    inLines[line].setup();
182                            }
183                            dst = super.filter( src, dst );
184                            intermediateLines = null;
185                            return dst;
186                    }
187                    return src;
188            }
189    
190            public String toString() {
191                    return "Distort/Field Warp...";
192            }
193    
194            public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src);
195                    Object o;
196                    if((o=parameters.removeEL(KeyImpl.init("Amount")))!=null)setAmount(ImageFilterUtil.toFloatValue(o,"Amount"));
197                    if((o=parameters.removeEL(KeyImpl.init("Power")))!=null)setPower(ImageFilterUtil.toFloatValue(o,"Power"));
198                    if((o=parameters.removeEL(KeyImpl.init("Strength")))!=null)setStrength(ImageFilterUtil.toFloatValue(o,"Strength"));
199                    if((o=parameters.removeEL(KeyImpl.init("InLines")))!=null)setInLines(ImageFilterUtil.toAFieldWarpFilter$Line(o,"InLines"));
200                    if((o=parameters.removeEL(KeyImpl.init("OutLines")))!=null)setOutLines(ImageFilterUtil.toAFieldWarpFilter$Line(o,"OutLines"));
201                    if((o=parameters.removeEL(KeyImpl.init("EdgeAction")))!=null)setEdgeAction(ImageFilterUtil.toString(o,"EdgeAction"));
202                    if((o=parameters.removeEL(KeyImpl.init("Interpolation")))!=null)setInterpolation(ImageFilterUtil.toString(o,"Interpolation"));
203    
204                    // check for arguments not supported
205                    if(parameters.size()>0) {
206                            throw new FunctionException(ThreadLocalPageContext.get(), "ImageFilter", 3, "parameters", "the parameter"+(parameters.size()>1?"s":"")+" ["+List.arrayToList(parameters.keysAsString(),", ")+"] "+(parameters.size()>1?"are":"is")+" not allowed, only the following parameters are supported [Amount, Power, Strength, InLines, OutLines, EdgeAction, Interpolation]");
207                    }
208    
209                    return filter(src, dst);
210            }
211    }