001// License: GPL. For details, see LICENSE file. 002 003package org.openstreetmap.josm.tools; 004 005import java.awt.Color; 006import java.awt.FontMetrics; 007import java.awt.Graphics2D; 008 009/** 010 * Utility class that helps to work with color scale 011 * for coloring GPX tracks etc. 012 * @since 7319 013 */ 014public class ColorScale { 015 private double min, max; 016 private Color noDataColor; 017 private Color belowMinColor; 018 private Color aboveMaxColor; 019 020 private Color[] colors; 021 private String title = ""; 022 private int intervalCount = 5; 023 024 private ColorScale() { 025 026 } 027 028 public static ColorScale createHSBScale(int count) { 029 ColorScale sc = new ColorScale(); 030 sc.colors = new Color[count]; 031 for (int i = 0; i < count; i++) { 032 sc.colors[i] = Color.getHSBColor(i / 300.0f, 1, 1); 033 } 034 sc.setRange(0, 255); 035 sc.addBounds(); 036 return sc; 037 } 038 039 public static ColorScale createCyclicScale(int count) { 040 ColorScale sc = new ColorScale(); 041 // red yellow green blue red 042 int[] h = new int[] { 0, 59, 127, 244, 360}; 043 int[] s = new int[] { 100, 84, 99, 100 }; 044 int[] b = new int[] { 90, 93, 74, 83 }; 045 046 sc.colors = new Color[count]; 047 for (int i = 0; i < sc.colors.length; i++) { 048 049 float angle = 4 - i / 256f * 4; 050 int quadrant = (int) angle; 051 angle -= quadrant; 052 quadrant = Utils.mod(quadrant+1, 4); 053 054 float vh = h[quadrant] * w(angle) + h[quadrant+1] * (1 - w(angle)); 055 float vs = s[quadrant] * w(angle) + s[Utils.mod(quadrant+1, 4)] * (1 - w(angle)); 056 float vb = b[quadrant] * w(angle) + b[Utils.mod(quadrant+1, 4)] * (1 - w(angle)); 057 058 sc.colors[i] = Color.getHSBColor(vh/360f, vs/100f, vb/100f); 059 } 060 sc.setRange(0, 2*Math.PI); 061 sc.addBounds(); 062 return sc; 063 } 064 065 /** 066 * transition function: 067 * w(0)=1, w(1)=0, 0<=w(x)<=1 068 * @param x number: 0<=x<=1 069 * @return the weighted value 070 */ 071 private static float w(float x) { 072 if (x < 0.5) 073 return 1 - 2*x*x; 074 else 075 return 2*(1-x)*(1-x); 076 } 077 078 public void setRange(double min, double max) { 079 this.min = min; 080 this.max = max; 081 } 082 083 /** 084 * Add standard colors for values below min or above max value 085 */ 086 public void addBounds() { 087 aboveMaxColor = colors[colors.length-1]; 088 belowMinColor = colors[0]; 089 } 090 091 public final Color getColor(double value) { 092 if (value<min) return belowMinColor; 093 if (value>max) return aboveMaxColor; 094 if (Double.isNaN(value)) return noDataColor; 095 final int n = colors.length; 096 int idx = (int) ((value-min)*colors.length / (max-min)); 097 if (idx<colors.length) { 098 return colors[idx]; 099 } else { 100 return colors[n-1]; // this happens when value==max 101 } 102 // int hdoplvl =(int) Math.round(colorModeDynamic ? ((hdop-minval)*255/(maxval-minval)) 103 // : (hdop <= 0 ? 0 : hdop * hdopfactor)); 104 // int hdopcolor = 255 - (hdoplvl > 255 ? 255 : hdoplvl); 105 } 106 107 public final Color getColor(Number value) { 108 return (value==null)? noDataColor : getColor(value.doubleValue()); 109 } 110 111 public Color getNoDataColor() { 112 113 return noDataColor; 114 } 115 116 public void setNoDataColor(Color noDataColor) { 117 this.noDataColor = noDataColor; 118 } 119 120 public ColorScale makeTransparent(int alpha) { 121 for (int i = 0; i < colors.length; i++) { 122 colors[i] = new Color((colors[i].getRGB() & 0xFFFFFF) | ((alpha & 0xFF) << 24), true); 123 } 124 return this; 125 } 126 127 public ColorScale addTitle(String title) { 128 this.title = title; 129 return this; 130 } 131 132 public ColorScale setIntervalCount(int intervalCount) { 133 this.intervalCount = intervalCount; 134 return this; 135 } 136 137 public ColorScale makeReversed() { 138 int n = colors.length; 139 Color tmp; 140 for (int i=0; i<n/2; i++) { 141 tmp = colors[i]; 142 colors[i] = colors[n-1-i]; 143 colors[n-1-i] = tmp; 144 } 145 tmp = belowMinColor; 146 belowMinColor = aboveMaxColor; 147 aboveMaxColor = tmp; 148 return this; 149 } 150 151 public void drawColorBar(Graphics2D g, int x, int y, int w, int h, double valueScale) { 152 int n=colors.length; 153 154 for (int i=0; i<n; i++) { 155 g.setColor(colors[i]); 156 if (w<h) { 157 g.fillRect(x, y+i*h/n, w, h/n+1); 158 } else { 159 g.fillRect(x+i*w/n, y, w/n+1, h); 160 } 161 } 162 163 int fw, fh; 164 FontMetrics fm = g.getFontMetrics(); 165 fh = fm.getHeight()/2; 166 fw = fm.stringWidth(String.valueOf(Math.max((int)Math.abs(max*valueScale), (int)Math.abs(min*valueScale)))) + fm.stringWidth("0.123"); 167 g.setColor(noDataColor); 168 if (title != null) { 169 g.drawString(title, x-fw-3, y-fh*3/2); 170 } 171 for (int i=0; i<=intervalCount; i++) { 172 g.setColor(colors[(int)(1.0*i*n/intervalCount-1e-10)]); 173 final double val = min+i*(max-min)/intervalCount; 174 final String txt = String.format("%.3f", val*valueScale); 175 if (w<h) { 176 g.drawString(txt, x-fw-3, y+i*h/intervalCount+fh/2); 177 } else { 178 g.drawString(txt, x+i*w/intervalCount-fw/2, y+fh-3); 179 } 180 } 181 } 182}