Add an option to color spots and tracks by a random color.

The random color for spots simply targets the GlasbeyLut class colors,
using the spot ID as index. This ensures the color does not 'move' when
the user edits it or change what is displayed.

For tracks, it simply reproduces the color for track index.

src/main/java/fiji/plugin/trackmate/features/FeatureUtils.java

@@ -41,6 +41,7 @@
 import fiji.plugin.trackmate.features.manual.ManualSpotColorAnalyzerFactory;
 import fiji.plugin.trackmate.features.spot.SpotAnalyzerFactoryBase;
 import fiji.plugin.trackmate.features.track.TrackAnalyzer;
+import fiji.plugin.trackmate.features.track.TrackIndexAnalyzer;
 import fiji.plugin.trackmate.gui.displaysettings.DisplaySettings;
 import fiji.plugin.trackmate.gui.displaysettings.DisplaySettings.TrackMateObject;
 import fiji.plugin.trackmate.visualization.FeatureColorGenerator;
@@ -51,6 +52,7 @@
 import fiji.plugin.trackmate.visualization.PerEdgeFeatureColorGenerator;
 import fiji.plugin.trackmate.visualization.PerSpotFeatureColorGenerator;
 import fiji.plugin.trackmate.visualization.PerTrackFeatureColorGenerator;
+import fiji.plugin.trackmate.visualization.RandomSpotColorGenerator;
 import fiji.plugin.trackmate.visualization.SpotColorGenerator;
 import fiji.plugin.trackmate.visualization.SpotColorGeneratorPerEdgeFeature;
 import fiji.plugin.trackmate.visualization.SpotColorGeneratorPerTrackFeature;
@@ -65,6 +67,10 @@ public class FeatureUtils
 
 	public static final String USE_UNIFORM_COLOR_KEY = "UNIFORM_COLOR";
 
+	private static final String USE_RANDOM_COLOR_NAME = "Random color";
+
+	public static final String USE_RANDOM_COLOR_KEY = "RANDOM_COLOR";
+
 	public static final Map< String, String > collectFeatureKeys( final TrackMateObject target, final Model model, final Settings settings )
 	{
 		final Map< String, String > inverseMap = new HashMap<>();
@@ -131,6 +137,7 @@ public static final Map< String, String > collectFeatureKeys( final TrackMateObj
 		case DEFAULT:
 		{
 			inverseMap.put( USE_UNIFORM_COLOR_NAME, USE_UNIFORM_COLOR_KEY );
+			inverseMap.put( USE_RANDOM_COLOR_NAME, USE_RANDOM_COLOR_KEY );
 			break;
 		}
 
@@ -218,7 +225,14 @@ public static final FeatureColorGenerator< Spot > createSpotColorGenerator( fina
 		switch ( displaySettings.getSpotColorByType() )
 		{
 		case DEFAULT:
-			return new UniformSpotColorGenerator( displaySettings.getSpotUniformColor() );
+			switch ( displaySettings.getSpotColorByFeature() )
+			{
+			case FeatureUtils.USE_RANDOM_COLOR_KEY:
+				return new RandomSpotColorGenerator();
+			default:
+			case FeatureUtils.USE_UNIFORM_COLOR_KEY:
+				return new UniformSpotColorGenerator( displaySettings.getSpotUniformColor() );
+			}
 
 		case EDGES:
 
@@ -267,7 +281,21 @@ public static final FeatureColorGenerator< DefaultWeightedEdge > createTrackColo
 		switch ( displaySettings.getTrackColorByType() )
 		{
 		case DEFAULT:
-			return new UniformTrackColorGenerator( displaySettings.getTrackUniformColor() );
+			switch ( displaySettings.getTrackColorByFeature() )
+			{
+			case FeatureUtils.USE_RANDOM_COLOR_KEY:
+				return new PerTrackFeatureColorGenerator(
+						model,
+						TrackIndexAnalyzer.TRACK_INDEX,
+						displaySettings.getMissingValueColor(),
+						displaySettings.getUndefinedValueColor(),
+						displaySettings.getColormap(),
+						displaySettings.getTrackMin(),
+						displaySettings.getTrackMax() );
+			default:
+			case FeatureUtils.USE_UNIFORM_COLOR_KEY:
+				return new UniformTrackColorGenerator( displaySettings.getTrackUniformColor() );
+			}
 
 		case EDGES:
 

src/main/java/fiji/plugin/trackmate/gui/components/FeatureDisplaySelector.java

@@ -76,6 +76,7 @@ public class FeatureDisplaySelector
 
 	private static final List< String > FEATURES_WITHOUT_MIN_MAX = Arrays.asList( new String[] {
 			FeatureUtils.USE_UNIFORM_COLOR_KEY,
+			FeatureUtils.USE_RANDOM_COLOR_KEY,
 			TrackIndexAnalyzer.TRACK_INDEX,
 			ManualEdgeColorAnalyzer.FEATURE,
 			ManualSpotColorAnalyzerFactory.FEATURE

src/main/java/fiji/plugin/trackmate/visualization/GlasbeyLut.java

@@ -26,7 +26,7 @@
 public class GlasbeyLut
 {
 
-	private static final Color[] colors = new Color[] {
+	public static final Color[] colors = new Color[] {
 			new Color( 255, 255, 255 ),
 			new Color( 20, 20, 255 ),
 			new Color( 255, 20, 20 ),

src/main/java/fiji/plugin/trackmate/visualization/RandomSpotColorGenerator.java

@@ -0,0 +1,16 @@
+package fiji.plugin.trackmate.visualization;
+
+import java.awt.Color;
+
+import fiji.plugin.trackmate.Spot;
+
+public class RandomSpotColorGenerator implements FeatureColorGenerator< Spot >
+{
+
+	@Override
+	public Color color( final Spot spot )
+	{
+		final int i = spot.ID() % GlasbeyLut.colors.length;
+		return GlasbeyLut.colors[ i ];
+	}
+}