Application: gvSIG desktop » gvSIG legends: base legends

package org.gvsig.legend.heatmap.lib.impl;

import java.awt.Color;

import java.awt.Graphics2D;

import java.awt.Image;

import java.awt.image.BufferedImage;

import java.util.Map;

import org.apache.commons.lang3.StringUtils;

import org.cresques.cts.ICoordTrans;

import org.gvsig.fmap.dal.exception.DataException;

import org.gvsig.fmap.dal.feature.Feature;

import org.gvsig.fmap.dal.feature.FeatureQuery;

import org.gvsig.fmap.dal.feature.FeatureSelection;

import org.gvsig.fmap.dal.feature.FeatureSet;

import org.gvsig.fmap.dal.feature.FeatureStore;

import org.gvsig.fmap.dal.feature.FeatureType;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.primitive.Point;

import org.gvsig.fmap.mapcontext.MapContextException;

import org.gvsig.fmap.mapcontext.ViewPort;

import org.gvsig.fmap.mapcontext.layers.operations.IHasImageLegend;

import org.gvsig.fmap.mapcontext.rendering.legend.LegendException;

import org.gvsig.fmap.mapcontext.rendering.legend.events.SymbolLegendEvent;

import org.gvsig.fmap.mapcontext.rendering.symbols.ISymbol;

import org.gvsig.gui.ColorTablePainter;

import org.gvsig.gui.DefaultColorTablePainter;

import org.gvsig.legend.heatmap.lib.api.HeatmapLegend;

import org.gvsig.symbology.fmap.mapcontext.rendering.legend.impl.AbstractVectorialLegend;

import org.gvsig.symbology.fmap.mapcontext.rendering.legend.impl.DefaultFeatureDrawnNotification;

import org.gvsig.symbology.fmap.mapcontext.rendering.symbol.text.impl.SimpleTextSymbol;

import org.gvsig.tools.exception.BaseException;

import org.gvsig.tools.task.Cancellable;

import org.gvsig.tools.visitor.VisitCanceledException;

import org.gvsig.tools.visitor.Visitor;

public class DefaultHeatmapLegend extends AbstractVectorialLegend implements HeatmapLegend, IHasImageLegend {

    private class DensityAlgorithm {

        private double[][] grid;

        private double[][] kernel;

        private int distance;

        private int height;

        private int with;

        private double maxValue;

        private double minValue;

        public DensityAlgorithm(int distance) {

            this.setDistance(distance);

        }

        public void setDistance(int distance) {

            this.distance = distance;

            this.kernel = new double[2 * this.distance + 1][2 * this.distance + 1];

            for( int y = -this.distance; y < this.distance + 1; y++ ) {

                for( int x = -this.distance; x < this.distance + 1; x++ ) {

                    final double dDist = Math.sqrt(x * x + y * y);

                    if( dDist < this.distance ) {

                        this.kernel[x + this.distance][y + this.distance] = Math.pow(1 - (dDist * dDist) / (this.distance * this.distance), 2);

                    } else {

                        this.kernel[x + this.distance][y + this.distance] = 0;

                    }

                }

            }

        }

        public int getDistance() {

            return this.distance;

        }

        public void init(int with, int height) {

            this.with = with;

            this.height = height;

            this.grid = new double[with][height];

            this.maxValue = 0;

            this.minValue = 0;

        }

        public void add(int px, int py) {

            add(px, py, 1);

        }

        public void add(int px, int py, double value) {

            for( int y = -this.distance; y < this.distance + 1; y++ ) {

                for( int x = -this.distance; x < this.distance + 1; x++ ) {

                    if( this.kernel[x + this.distance][y + this.distance] != 0 ) {

                        addValue(px + x, py + y, value * this.kernel[x + this.distance][y + this.distance]);

                    }

                }

            }

        }

        private void addValue(int px, int py, double value) {

            if( px < 0 || py < 0 || px >= with || py >= height ) {

                return;

            }

            value += this.grid[px][py];

            this.grid[px][py] = value;

            if( value > this.maxValue ) {

                this.maxValue = value;

            }

            if( value < this.minValue ) {

                this.minValue = value;

            }

        }

        public void draw(BufferedImage img, Graphics2D g, Color[] colorTable, int alphaHot, int alphaCold, Cancellable cancel) {

            try {

                Color c;

                int maxColors = colorTable.length;

                double deltaAlpha = (alphaHot - alphaCold) / maxColors;

                for( int x = 0; x < with; x++ ) {

                    for( int y = 0; y < height; y++ ) {

                        if( cancel.isCanceled() ) {

                            return;

                        }

                        double value = this.grid[x][y];

                        if( value > 0 ) {

                            int icolor = (int) (value * maxColors / maxValue);

                            icolor = icolor < 0 ? 0 : icolor >= maxColors ? maxColors - 1 : icolor;

                            if( alphaHot > 0 ) {

                                c = colorTable[icolor];

                                c = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int) (icolor * deltaAlpha) & 0xff);

                            } else {

                                c = colorTable[icolor];

                            }

                            c = blend(new Color(img.getRGB(x, y)),c);

                            img.setRGB(x, y, c.getRGB());

                        }

                    }

                }

            } catch (Exception ex) {

                LOG.warn("Problems drawing heatmap", ex);

            }

        }

        private Color blend(Color dst, Color src) {

            //

            // https://en.wikipedia.org/wiki/Alpha_compositing#Alpha_blending

            //

            // when the destination background is opaque

            //

            // double outa = 1;

            double srca = src.getAlpha() / 255.0;

            double srca_1 = (1 - srca);

            Color color = new Color(

                (int)(src.getRed()  * srca + dst.getRed()  * srca_1) & 0xff,

                (int)(src.getGreen()* srca + dst.getGreen()* srca_1) & 0xff,

                (int)(src.getBlue() * srca + dst.getBlue() * srca_1) & 0xff

            );

            return color;

        }

    }

    private final ISymbol defaultSymbol;

    private final DensityAlgorithm algorithm;

    private boolean isRamp;

    private Color[] colorTable;

    private int colorTableHotColorAlpha;

    private int colorTableColdColorAlpha;

    private String fieldName;

    private boolean useAlphaInColorTable;

    private Image imageLegend;

    public DefaultHeatmapLegend() {

        this.defaultSymbol = new SimpleTextSymbol();

        this.algorithm = new DensityAlgorithm(30);

        this.colorTableHotColorAlpha = 255;

        this.colorTableColdColorAlpha = 0;

        this.useAlphaInColorTable = false;

        this.setColorTable(100, new Color(0, 0, 255, 1), new Color(255, 0, 0, 255));

        this.imageLegend = null;

    }

    @Override

    protected String[] getRequiredFeatureAttributeNames(FeatureStore featureStore) throws DataException {

        FeatureType ftype = featureStore.getDefaultFeatureType();

        if( StringUtils.isEmpty(this.fieldName) ) {

            return new String[]{

                ftype.getDefaultGeometryAttributeName()

            };

        }

        return new String[]{

            ftype.getDefaultGeometryAttributeName(),

            this.fieldName

        };

    }

    @Override

    public ISymbol getDefaultSymbol() {

        return this.defaultSymbol;

    }

    @Override

    public void setDefaultSymbol(ISymbol is) {

    }

    @Override

    public ISymbol getSymbolByFeature(Feature ftr) throws MapContextException {

        return this.defaultSymbol;

    }

    @Override

    public int getShapeType() {

        return Geometry.TYPES.GEOMETRY;

    }

    @Override

    public void setShapeType(int i) {

    }

    @Override

    public boolean isUseDefaultSymbol() {

        return true;

    }

    @Override

    public void useDefaultSymbol(boolean bln) {

    }

    @Override

    public boolean isSuitableForShapeType(int shapeType) {

        return true;

    }

    @Override

    protected void draw(BufferedImage image, Graphics2D g, ViewPort viewPort, Cancellable cancel, double scale, Map queryParameters, ICoordTrans coordTrans, FeatureStore featureStore, FeatureQuery featureQuery, double dpi) throws LegendException {

        this.algorithm.init(image.getWidth(), image.getHeight());

        super.draw(image, g, viewPort, cancel, scale, queryParameters, coordTrans, featureStore, featureQuery, dpi);

        if( !cancel.isCanceled() ) {

            if( this.useRamp() || !useAlphaInColorTable ) {

                this.algorithm.draw(image, g, this.getColorTable(), -1, -1, cancel);

            } else {

                this.algorithm.draw(image, g, this.getColorTable(), colorTableHotColorAlpha, colorTableColdColorAlpha, cancel);

            }

        }

    }

    @Override

    protected void drawFeatures(

        BufferedImage image,

        Graphics2D g,

        final ViewPort viewPort,

        final Cancellable cancel,

        final ICoordTrans coordTrans,

        double dpi,

        DefaultFeatureDrawnNotification drawnNotification,

        FeatureSet featureSet,

        FeatureSelection selection

    ) throws BaseException {

        int x = -1;

        if( !StringUtils.isEmpty(this.fieldName) ) {

            x = featureSet.getDefaultFeatureType().getIndex(this.fieldName);

        }

        final int n = x;

        featureSet.accept(new Visitor() {

            @Override

            public void visit(Object o) throws VisitCanceledException, BaseException {

                if( cancel.isCanceled() ) {

                    throw new VisitCanceledException();

                }

                Feature feature = (Feature) o;

                Geometry geom = feature.getDefaultGeometry();

                if( geom != null ) {

                    Point pointGeo = geom.centroid();

                    if( coordTrans != null ) {

                        pointGeo.reProject(coordTrans);

                    }

                    Point pointPixels = (Point) pointGeo.cloneGeometry();

                    pointPixels.transform(viewPort.getAffineTransform());

                    if( n >= 0 ) {

                        double value = 0;

                        try {

                            value = feature.getDouble(n);

                        } catch(Exception ex) {   

                        }

                        if( value >0 ) {

                            algorithm.add((int) pointPixels.getX(), (int) pointPixels.getY(), value);

                        }

                    } else {

                        algorithm.add((int) pointPixels.getX(), (int) pointPixels.getY());

                    }

                }

            }

        });

    }

    /**

     * @return the distance

     */

    @Override

    public int getDistance() {

        return this.algorithm.getDistance();

    }

    /**

     * @param distance the distance to set

     */

    @Override

    public void setDistance(int distance) {

        this.algorithm.setDistance(distance);

    }

    @Override

    public void setColorTable(Color[] colorTable) {

        this.isRamp = false;

        this.colorTable = colorTable;

        this.imageLegend = null;

        this.fireDefaultSymbolChangedEvent(new SymbolLegendEvent(null,null));

    }

    @Override

    public void setColorTable(int numColor, Color first, Color last) {

        Color[] table = new Color[numColor];

        double deltaRed = (last.getRed() - first.getRed()) / numColor;

        double deltaGreen = (last.getGreen() - first.getGreen()) / numColor;

        double deltaBlue = (last.getBlue() - first.getBlue()) / numColor;

        double deltaAlpha = (last.getAlpha() - first.getAlpha()) / numColor;

        for( int i = 0; i < numColor; i++ ) {

            table[i] = new Color(

                (int) (first.getRed() + i * deltaRed),

                (int) (first.getGreen() + i * deltaGreen),

                (int) (first.getBlue() + i * deltaBlue),

                (int) (first.getAlpha() + i * deltaAlpha)

            );

        }

        this.isRamp = true;

        this.colorTable = table;

        this.imageLegend = null;

        this.fireDefaultSymbolChangedEvent(new SymbolLegendEvent(null,null));

    }

    @Override

    public Color[] getColorTable() {

        return this.colorTable;

    }

    @Override

    public boolean useRamp() {

        return this.isRamp;

    }

    @Override

    public String getFieldName() {

        return this.fieldName;

    }

    @Override

    public void setFieldName(String fieldName) {

        this.fieldName = fieldName;

    }

    @Override

    public int getColorTableHotColorAlpha() {

        return colorTableHotColorAlpha;

    }

    @Override

    public void setColorTableHotColorAlpha(int colorTableHotColorAlpha) {

        this.colorTableHotColorAlpha = colorTableHotColorAlpha;

    }

    @Override

    public int getColorTableColdColorAlpha() {

        return colorTableColdColorAlpha;

    }

    @Override

    public void setColorTableColdColorAlpha(int colorTableColdColorAlpha) {

        this.colorTableColdColorAlpha = colorTableColdColorAlpha;

    }

    @Override

    public boolean useAlphaInColorTable() {

        return this.useAlphaInColorTable;

    }

    @Override

    public boolean setUseAlphaInColorTable(boolean use) {

        boolean x = this.useAlphaInColorTable;

        this.useAlphaInColorTable = use;

        return x;

    }

    @Override

    public Image getImageLegend() {

        if( this.imageLegend==null ) {

            BufferedImage img = new BufferedImage(80, 20, BufferedImage.TYPE_INT_RGB);

            ColorTablePainter painter = new DefaultColorTablePainter(this.colorTable,"");

            Graphics2D g = img.createGraphics();

            g.setClip(0, 0, 150, 20);

            painter.paint(g, false);

            this.imageLegend = img;

        }

        return this.imageLegend;

    }

    @Override

    public String getPathImage() {

        return null;

    }

}