Merge pull request #214 into master

Slider redesign

flatlaf-core/src/main/java/com/formdev/flatlaf/IntelliJTheme.java

@@ -475,7 +475,9 @@ public class IntelliJTheme
 		}
 	}
 
+	/** Rename UI default keys (key --> value). */
 	private static Map<String, String> uiKeyMapping = new HashMap<>();
+	/** Copy UI default keys (value --> key). */
 	private static Map<String, String> uiKeyCopying = new HashMap<>();
 	private static Map<String, String> uiKeyInverseMapping = new HashMap<>();
 	private static Map<String, String> checkboxKeyMapping = new HashMap<>();
@@ -529,6 +531,9 @@ public class IntelliJTheme
 
 		// Slider
 		uiKeyMapping.put( "Slider.trackWidth", "" ); // ignore (used in Material Theme UI Lite)
+		uiKeyCopying.put( "Slider.trackValueColor", "ProgressBar.foreground" );
+		uiKeyCopying.put( "Slider.thumbColor", "ProgressBar.foreground" );
+		uiKeyCopying.put( "Slider.trackColor", "ProgressBar.background" );
 
 		// TitlePane
 		uiKeyCopying.put( "TitlePane.inactiveBackground",     "TitlePane.background" );

flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java

@@ -586,13 +586,17 @@ class UIDefaultsLoader
 			case "darken":		return parseColorHSLIncreaseDecrease( 2, false, params, resolver, reportError );
 			case "saturate":	return parseColorHSLIncreaseDecrease( 1, true, params, resolver, reportError );
 			case "desaturate":	return parseColorHSLIncreaseDecrease( 1, false, params, resolver, reportError );
+			case "fadein":		return parseColorHSLIncreaseDecrease( 3, true, params, resolver, reportError );
+			case "fadeout":		return parseColorHSLIncreaseDecrease( 3, false, params, resolver, reportError );
+			case "fade":		return parseColorFade( params, resolver, reportError );
+			case "spin":		return parseColorSpin( params, resolver, reportError );
 		}
 
 		throw new IllegalArgumentException( "unknown color function '" + value + "'" );
 	}
 
 	/**
-	 * Syntax: rgb(red,green,blue) or rgba(red,green,blue,alpha) or rgba(color,alpha)
+	 * Syntax: rgb(red,green,blue) or rgba(red,green,blue,alpha)
 	 *   - red:   an integer 0-255 or a percentage 0-100%
 	 *   - green: an integer 0-255 or a percentage 0-100%
 	 *   - blue:  an integer 0-255 or a percentage 0-100%
@@ -603,6 +607,8 @@ class UIDefaultsLoader
 	{
 		if( hasAlpha && params.size() == 2 ) {
 			// syntax rgba(color,alpha), which allows adding alpha to any color
+			// NOTE: this syntax is deprecated
+			//       use fade(color,alpha) instead
 			String colorStr = params.get( 0 );
 			int alpha = parseInteger( params.get( 1 ), 0, 255, true );
 
@@ -639,7 +645,8 @@ class UIDefaultsLoader
 
 	/**
 	 * Syntax: lighten(color,amount[,options]) or darken(color,amount[,options]) or
-	 *         saturate(color,amount[,options]) or desaturate(color,amount[,options])
+	 *         saturate(color,amount[,options]) or desaturate(color,amount[,options]) or
+	 *         fadein(color,amount[,options]) or fadeout(color,amount[,options])
 	 *   - color: a color (e.g. #f00) or a color function
 	 *   - amount: percentage 0-100%
 	 *   - options: [relative] [autoInverse] [noAutoInverse] [lazy] [derived]
@@ -679,6 +686,59 @@ class UIDefaultsLoader
 			};
 		}
 
+		// parse base color, apply function and create derived color
+		return parseFunctionBaseColor( colorStr, function, derived, resolver, reportError );
+	}
+
+	/**
+	 * Syntax: fade(color,amount[,options])
+	 *   - color: a color (e.g. #f00) or a color function
+	 *   - amount: percentage 0-100%
+	 *   - options: [derived]
+	 */
+	private static Object parseColorFade( List<String> params, Function<String, String> resolver, boolean reportError ) {
+		String colorStr = params.get( 0 );
+		int amount = parsePercentage( params.get( 1 ) );
+		boolean derived = false;
+
+		if( params.size() > 2 ) {
+			String options = params.get( 2 );
+			derived = options.contains( "derived" );
+		}
+
+		// create function
+		ColorFunction function = new ColorFunctions.Fade( amount );
+
+		// parse base color, apply function and create derived color
+		return parseFunctionBaseColor( colorStr, function, derived, resolver, reportError );
+	}
+
+	/**
+	 * Syntax: spin(color,angle[,options])
+	 *   - color: a color (e.g. #f00) or a color function
+	 *   - angle: number of degrees to rotate
+	 *   - options: [derived]
+	 */
+	private static Object parseColorSpin( List<String> params, Function<String, String> resolver, boolean reportError ) {
+		String colorStr = params.get( 0 );
+		int amount = parseInteger( params.get( 1 ), true );
+		boolean derived = false;
+
+		if( params.size() > 2 ) {
+			String options = params.get( 2 );
+			derived = options.contains( "derived" );
+		}
+
+		// create function
+		ColorFunction function = new ColorFunctions.HSLIncreaseDecrease( 0, true, amount, false, false );
+
+		// parse base color, apply function and create derived color
+		return parseFunctionBaseColor( colorStr, function, derived, resolver, reportError );
+	}
+
+	private static Object parseFunctionBaseColor( String colorStr, ColorFunction function,
+		boolean derived, Function<String, String> resolver, boolean reportError )
+	{
 		// parse base color
 		String resolvedColorStr = resolver.apply( colorStr );
 		ColorUIResource baseColor = (ColorUIResource) parseColorOrFunction( resolvedColorStr, resolver, reportError );

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatSliderUI.java

@@ -18,17 +18,23 @@ package com.formdev.flatlaf.ui;
 
 import java.awt.Color;
 import java.awt.Dimension;
+import java.awt.FontMetrics;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
-import java.awt.event.MouseListener;
+import java.awt.Rectangle;
+import java.awt.Shape;
+import java.awt.event.MouseEvent;
+import java.awt.geom.Ellipse2D;
 import java.awt.geom.Path2D;
 import java.awt.geom.RoundRectangle2D;
 import javax.swing.JComponent;
 import javax.swing.JSlider;
 import javax.swing.LookAndFeel;
+import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.basic.BasicSliderUI;
+import com.formdev.flatlaf.util.HiDPIUtils;
 import com.formdev.flatlaf.util.UIScale;
 
 /**
@@ -49,29 +55,44 @@ import com.formdev.flatlaf.util.UIScale;
  * <!-- FlatSliderUI -->
  *
  * @uiDefault Slider.trackWidth				int
- * @uiDefault Slider.thumbWidth				int
+ * @uiDefault Slider.thumbSize				Dimension
+ * @uiDefault Slider.focusWidth				int
+ * @uiDefault Slider.trackValueColor		Color	optional; defaults to Slider.thumbColor
  * @uiDefault Slider.trackColor				Color
  * @uiDefault Slider.thumbColor				Color
+ * @uiDefault Slider.thumbBorderColor		Color	optional; if null, no border is painted
  * @uiDefault Slider.focusedColor			Color	optional; defaults to Component.focusColor
- * @uiDefault Slider.hoverColor				Color	optional; defaults to Slider.focusedColor
- * @uiDefault Slider.disabledForeground		Color	used for track and thumb is disabled
+ * @uiDefault Slider.focusedThumbBorderColor Color	optional; defaults to Component.focusedBorderColor
+ * @uiDefault Slider.hoverThumbColor		Color	optional
+ * @uiDefault Slider.pressedThumbColor		Color	optional
+ * @uiDefault Slider.disabledTrackColor		Color
+ * @uiDefault Slider.disabledThumbColor		Color
+ * @uiDefault Slider.disabledThumbBorderColor Color	optional; defaults to Component.disabledBorderColor
  *
  * @author Karl Tauber
  */
 public class FlatSliderUI
 	extends BasicSliderUI
 {
-	private int trackWidth;
-	private int thumbWidth;
+	protected int trackWidth;
+	protected Dimension thumbSize;
+	protected int focusWidth;
 
-	private Color trackColor;
-	private Color thumbColor;
-	private Color focusColor;
-	private Color hoverColor;
-	private Color disabledForeground;
+	protected Color trackValueColor;
+	protected Color trackColor;
+	protected Color thumbColor;
+	protected Color thumbBorderColor;
+	protected Color focusBaseColor;
+	protected Color focusedColor;
+	protected Color focusedThumbBorderColor;
+	protected Color hoverThumbColor;
+	protected Color pressedThumbColor;
+	protected Color disabledTrackColor;
+	protected Color disabledThumbColor;
+	protected Color disabledThumbBorderColor;
 
-	private MouseListener hoverListener;
-	private boolean hover;
+	protected boolean thumbHover;
+	protected boolean thumbPressed;
 
 	public static ComponentUI createUI( JComponent c ) {
 		return new FlatSliderUI();
@@ -81,24 +102,6 @@ public class FlatSliderUI
 		super( null );
 	}
 
-	@Override
-	protected void installListeners( JSlider slider ) {
-		super.installListeners( slider );
-
-		hoverListener = new FlatUIUtils.HoverListener( slider, h -> {
-			hover = h;
-		} );
-		slider.addMouseListener( hoverListener );
-	}
-
-	@Override
-	protected void uninstallListeners( JSlider slider ) {
-		super.uninstallListeners( slider );
-
-		slider.removeMouseListener( hoverListener );
-		hoverListener = null;
-	}
-
 	@Override
 	protected void installDefaults( JSlider slider ) {
 		super.installDefaults( slider );
@@ -106,24 +109,65 @@ public class FlatSliderUI
 		LookAndFeel.installProperty( slider, "opaque", false );
 
 		trackWidth = UIManager.getInt( "Slider.trackWidth" );
-		thumbWidth = UIManager.getInt( "Slider.thumbWidth" );
+		thumbSize = UIManager.getDimension( "Slider.thumbSize" );
+		if( thumbSize == null ) {
+			// fallback for compatibility with old versions
+			int thumbWidth = UIManager.getInt( "Slider.thumbWidth" );
+			thumbSize = new Dimension( thumbWidth, thumbWidth );
+		}
+		focusWidth = FlatUIUtils.getUIInt( "Slider.focusWidth", 4 );
 
+		trackValueColor = FlatUIUtils.getUIColor( "Slider.trackValueColor", "Slider.thumbColor" );
 		trackColor = UIManager.getColor( "Slider.trackColor" );
 		thumbColor = UIManager.getColor( "Slider.thumbColor" );
-		focusColor = FlatUIUtils.getUIColor( "Slider.focusedColor", "Component.focusColor" );
-		hoverColor = FlatUIUtils.getUIColor( "Slider.hoverColor", focusColor );
-		disabledForeground = UIManager.getColor( "Slider.disabledForeground" );
+		thumbBorderColor = UIManager.getColor( "Slider.thumbBorderColor" );
+		focusBaseColor = UIManager.getColor( "Component.focusColor" );
+		focusedColor = FlatUIUtils.getUIColor( "Slider.focusedColor", focusBaseColor );
+		focusedThumbBorderColor = FlatUIUtils.getUIColor( "Slider.focusedThumbBorderColor", "Component.focusedBorderColor" );
+		hoverThumbColor = UIManager.getColor( "Slider.hoverThumbColor" );
+		pressedThumbColor = UIManager.getColor( "Slider.pressedThumbColor" );
+		disabledTrackColor = UIManager.getColor( "Slider.disabledTrackColor" );
+		disabledThumbColor = UIManager.getColor( "Slider.disabledThumbColor" );
+		disabledThumbBorderColor = FlatUIUtils.getUIColor( "Slider.disabledThumbBorderColor", "Component.disabledBorderColor" );
 	}
 
 	@Override
 	protected void uninstallDefaults( JSlider slider ) {
 		super.uninstallDefaults( slider );
 
+		trackValueColor = null;
 		trackColor = null;
 		thumbColor = null;
-		focusColor = null;
-		hoverColor = null;
-		disabledForeground = null;
+		thumbBorderColor = null;
+		focusBaseColor = null;
+		focusedColor = null;
+		focusedThumbBorderColor = null;
+		hoverThumbColor = null;
+		pressedThumbColor = null;
+		disabledTrackColor = null;
+		disabledThumbColor = null;
+		disabledThumbBorderColor = null;
+	}
+
+	@Override
+	protected TrackListener createTrackListener( JSlider slider ) {
+		return new FlatTrackListener();
+	}
+
+	@Override
+	public int getBaseline( JComponent c, int width, int height ) {
+		if( c == null )
+			throw new NullPointerException();
+		if( width < 0 || height < 0 )
+			throw new IllegalArgumentException();
+
+		// no baseline for vertical orientation
+		if( slider.getOrientation() == JSlider.VERTICAL )
+			return -1;
+
+		// compute a baseline so that the track is vertically centered
+		FontMetrics fm = slider.getFontMetrics( slider.getFont() );
+		return trackRect.y + Math.round( (trackRect.height - fm.getHeight()) / 2f ) + fm.getAscent() - 1;
 	}
 
 	@Override
@@ -153,13 +197,35 @@ public class FlatSliderUI
 
 	@Override
 	protected Dimension getThumbSize() {
-		return new Dimension( UIScale.scale( thumbWidth ), UIScale.scale( thumbWidth ) );
+		return calcThumbSize( slider, thumbSize, focusWidth );
+	}
+
+	public static Dimension calcThumbSize( JSlider slider, Dimension thumbSize, int focusWidth ) {
+		int fw = UIScale.scale( focusWidth );
+		int w = UIScale.scale( thumbSize.width ) + fw + fw;
+		int h = UIScale.scale( thumbSize.height ) + fw + fw;
+		return (slider.getOrientation() == JSlider.HORIZONTAL)
+			? new Dimension( w, h )
+			: new Dimension( h, w );
 	}
 
 	@Override
 	public void paint( Graphics g, JComponent c ) {
 		FlatUIUtils.setRenderingHints( (Graphics2D) g );
 
+/*debug
+		g.setColor( Color.gray );
+		g.drawRect( 0, 0, c.getWidth() - 1, c.getHeight() - 1 );
+		g.setColor( Color.orange );
+		g.drawRect( focusRect.x, focusRect.y, focusRect.width - 1, focusRect.height - 1 );
+		g.setColor( Color.magenta );
+		g.drawRect( contentRect.x, contentRect.y, contentRect.width - 1, contentRect.height - 1 );
+		g.setColor( Color.blue );
+		g.drawRect( trackRect.x, trackRect.y, trackRect.width - 1, trackRect.height - 1 );
+		g.setColor( Color.red );
+		g.drawRect( thumbRect.x, thumbRect.y, thumbRect.width - 1, thumbRect.height - 1 );
+debug*/
+
 		super.paint( g, c );
 	}
 
@@ -201,50 +267,248 @@ public class FlatSliderUI
 		}
 
 		if( coloredTrack != null ) {
-			g.setColor( FlatUIUtils.deriveColor( FlatUIUtils.isPermanentFocusOwner( slider ) ? focusColor : (hover ? hoverColor : thumbColor), thumbColor ) );
+			g.setColor( trackValueColor );
 			((Graphics2D)g).fill( coloredTrack );
 		}
 
-		g.setColor( enabled ? trackColor : disabledForeground );
+		g.setColor( enabled ? trackColor : disabledTrackColor );
 		((Graphics2D)g).fill( track );
 	}
 
 	@Override
 	public void paintThumb( Graphics g ) {
-		g.setColor( FlatUIUtils.deriveColor( slider.isEnabled()
-			? (FlatUIUtils.isPermanentFocusOwner( slider ) ? focusColor : (hover ? hoverColor : thumbColor))
-			: disabledForeground,
-			thumbColor ) );
+		Color color = stateColor( slider, thumbHover, thumbPressed,
+			thumbColor, disabledThumbColor, null, hoverThumbColor, pressedThumbColor );
+		color = FlatUIUtils.deriveColor( color, thumbColor );
 
-		if( isRoundThumb() )
-			g.fillOval( thumbRect.x, thumbRect.y, thumbRect.width, thumbRect.height );
-		else {
-			double w = thumbRect.width;
-			double h = thumbRect.height;
-			double wh = w / 2;
+		Color borderColor = (thumbBorderColor != null)
+			? stateColor( slider, false, false, thumbBorderColor, disabledThumbBorderColor, focusedThumbBorderColor, null, null )
+			: null;
 
-			Path2D thumb = FlatUIUtils.createPath( 0,0, w,0, w,(h - wh), wh,h,  0,(h - wh) );
+		Color focusedColor = FlatUIUtils.deriveColor( this.focusedColor, focusBaseColor );
 
+		paintThumb( g, slider, thumbRect, isRoundThumb(), color, borderColor, focusedColor, focusWidth );
+	}
+
+	public static void paintThumb( Graphics g, JSlider slider, Rectangle thumbRect, boolean roundThumb,
+		Color thumbColor, Color thumbBorderColor, Color focusedColor, int focusWidth )
+	{
+		double systemScaleFactor = UIScale.getSystemScaleFactor( (Graphics2D) g );
+		if( systemScaleFactor != 1 && systemScaleFactor != 2 ) {
+			// paint at scale 1x to avoid clipping on right and bottom edges at 125%, 150% or 175%
+			HiDPIUtils.paintAtScale1x( (Graphics2D) g, thumbRect.x, thumbRect.y, thumbRect.width, thumbRect.height,
+				(g2d, x2, y2, width2, height2, scaleFactor) -> {
+					paintThumbImpl( g, slider, x2, y2, width2, height2,
+						roundThumb, thumbColor, thumbBorderColor, focusedColor,
+						(float) (focusWidth * scaleFactor) );
+				} );
+			return;
+		}
+
+		paintThumbImpl( g, slider, thumbRect.x, thumbRect.y, thumbRect.width, thumbRect.height,
+			roundThumb, thumbColor, thumbBorderColor, focusedColor, focusWidth );
+
+	}
+
+	private static void paintThumbImpl( Graphics g, JSlider slider, int x, int y, int width, int height,
+		boolean roundThumb, Color thumbColor, Color thumbBorderColor, Color focusedColor, float focusWidth )
+	{
+		int fw = Math.round( UIScale.scale( focusWidth ) );
+		int tx = x + fw;
+		int ty = y + fw;
+		int tw = width - fw - fw;
+		int th = height - fw - fw;
+		boolean focused = FlatUIUtils.isPermanentFocusOwner( slider );
+
+		if( roundThumb ) {
+			// paint thumb focus border
+			if( focused ) {
+				g.setColor( focusedColor );
+				((Graphics2D)g).fill( createRoundThumbShape( x, y, width, height ) );
+			}
+
+			if( thumbBorderColor != null ) {
+				// paint thumb border
+				g.setColor( thumbBorderColor );
+				((Graphics2D)g).fill( createRoundThumbShape( tx, ty, tw, th ) );
+
+				// paint thumb background
+				float lw = UIScale.scale( 1f );
+				g.setColor( thumbColor );
+				((Graphics2D)g).fill( createRoundThumbShape( tx + lw, ty + lw,
+					tw - lw - lw, th - lw - lw ) );
+			} else {
+				// paint thumb background
+				g.setColor( thumbColor );
+				((Graphics2D)g).fill( createRoundThumbShape( tx, ty, tw, th ) );
+			}
+		} else {
 			Graphics2D g2 = (Graphics2D) g.create();
 			try {
-				g2.translate( thumbRect.x, thumbRect.y );
+				g2.translate( x, y );
 				if( slider.getOrientation() == JSlider.VERTICAL ) {
 					if( slider.getComponentOrientation().isLeftToRight() ) {
-						g2.translate( 0, thumbRect.height );
+						g2.translate( 0, height );
 						g2.rotate( Math.toRadians( 270 ) );
 					} else {
-						g2.translate( thumbRect.width, 0 );
+						g2.translate( width, 0 );
 						g2.rotate( Math.toRadians( 90 ) );
 					}
+
+					// rotate thumb width/height
+					int temp = tw;
+					tw = th;
+					th = temp;
+				}
+
+				// paint thumb focus border
+				if( focused ) {
+					g2.setColor( focusedColor );
+					g2.fill( createDirectionalThumbShape( 0, 0,
+						tw + fw + fw, th + fw + fw + (fw * 0.4142f), fw ) );
+				}
+
+				if( thumbBorderColor != null ) {
+					// paint thumb border
+					g2.setColor( thumbBorderColor );
+					g2.fill( createDirectionalThumbShape( fw, fw, tw, th, 0 ) );
+
+					// paint thumb background
+					float lw = UIScale.scale( 1f );
+					g2.setColor( thumbColor );
+					g2.fill( createDirectionalThumbShape( fw + lw, fw + lw,
+						tw - lw - lw, th - lw - lw - (lw * 0.4142f), 0 ) );
+				} else {
+					// paint thumb background
+					g2.setColor( thumbColor );
+					g2.fill( createDirectionalThumbShape( fw, fw, tw, th, 0 ) );
 				}
-				g2.fill( thumb );
 			} finally {
 				g2.dispose();
 			}
 		}
 	}
 
-	private boolean isRoundThumb() {
+	public static Shape createRoundThumbShape( float x, float y, float w, float h ) {
+		if( w == h )
+			return new Ellipse2D.Float( x, y, w, h );
+		else {
+			float arc = Math.min( w, h );
+			return new RoundRectangle2D.Float( x, y, w, h, arc, arc );
+		}
+	}
+
+	public static Shape createDirectionalThumbShape( float x, float y, float w, float h, float arc ) {
+		float wh = w / 2;
+
+		Path2D path = new Path2D.Float();
+		path.moveTo( x + wh, y + h );
+		path.lineTo( x, y + (h - wh) );
+		path.lineTo( x, y + arc );
+		path.quadTo( x, y, x + arc, y );
+		path.lineTo( x + (w - arc), y );
+		path.quadTo( x + w, y, x + w, y + arc );
+		path.lineTo( x + w, y + (h - wh) );
+		path.closePath();
+
+		return path;
+	}
+
+	public static Color stateColor( JSlider slider, boolean hover, boolean pressed,
+		Color enabledColor, Color disabledColor, Color focusedColor, Color hoverColor, Color pressedColor )
+	{
+		if( disabledColor != null && !slider.isEnabled() )
+			return disabledColor;
+		if( pressedColor != null && pressed )
+			return pressedColor;
+		if( hoverColor != null && hover )
+			return hoverColor;
+		if( focusedColor != null && FlatUIUtils.isPermanentFocusOwner( slider ) )
+			return focusedColor;
+		return enabledColor;
+	}
+
+	protected boolean isRoundThumb() {
 		return !slider.getPaintTicks() && !slider.getPaintLabels();
 	}
+
+	@Override
+	public void setThumbLocation( int x, int y ) {
+		if( !isRoundThumb() ) {
+			// the needle of the directional thumb is painted outside of thumbRect
+			// --> must increase repaint rectangle
+
+			// set new thumb location and compute union of old and new thumb bounds
+			Rectangle r = new Rectangle( thumbRect );
+			thumbRect.setLocation( x, y );
+			SwingUtilities.computeUnion( thumbRect.x, thumbRect.y, thumbRect.width, thumbRect.height, r );
+
+			// increase union rectangle for repaint
+			int extra = (int) Math.ceil( UIScale.scale( focusWidth ) * 0.4142f );
+			if( slider.getOrientation() == JSlider.HORIZONTAL )
+				r.height += extra;
+			else {
+				r.width += extra;
+				if( !slider.getComponentOrientation().isLeftToRight() )
+					r.x -= extra;
+			}
+
+			slider.repaint( r );
+		} else
+			super.setThumbLocation( x, y );
+	}
+
+	//---- class FlatTrackListener --------------------------------------------
+
+	protected class FlatTrackListener
+		extends TrackListener
+	{
+		@Override
+		public void mouseEntered( MouseEvent e ) {
+			setThumbHover( isOverThumb( e ) );
+			super.mouseEntered( e );
+		}
+
+		@Override
+		public void mouseExited( MouseEvent e ) {
+			setThumbHover( false );
+			super.mouseExited( e );
+		}
+
+		@Override
+		public void mouseMoved( MouseEvent e ) {
+			setThumbHover( isOverThumb( e ) );
+			super.mouseMoved( e );
+		}
+
+		@Override
+		public void mousePressed( MouseEvent e ) {
+			setThumbPressed( isOverThumb( e ) );
+			super.mousePressed( e );
+		}
+
+		@Override
+		public void mouseReleased( MouseEvent e ) {
+			setThumbPressed( false );
+			super.mouseReleased( e );
+		}
+
+		protected void setThumbHover( boolean hover ) {
+			if( hover != thumbHover ) {
+				thumbHover = hover;
+				slider.repaint( thumbRect );
+			}
+		}
+
+		protected void setThumbPressed( boolean pressed ) {
+			if( pressed != thumbPressed ) {
+				thumbPressed = pressed;
+				slider.repaint( thumbRect );
+			}
+		}
+
+		protected boolean isOverThumb( MouseEvent e ) {
+			return e != null && slider.isEnabled() && thumbRect.contains( e.getX(), e.getY() );
+		}
+	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/util/ColorFunctions.java

@@ -28,11 +28,12 @@ public class ColorFunctions
 	public static Color applyFunctions( Color color, ColorFunction... functions ) {
 		float[] hsl = HSLColor.fromRGB( color );
 		float alpha = color.getAlpha() / 255f;
+		float[] hsla = { hsl[0], hsl[1], hsl[2], alpha * 100 };
 
 		for( ColorFunction function : functions )
-			function.apply( hsl );
+			function.apply( hsla );
 
-		return HSLColor.toRGB( hsl, alpha );
+		return HSLColor.toRGB( hsla[0], hsla[1], hsla[2], hsla[3] / 100 );
 	}
 
 	public static float clamp( float value ) {
@@ -46,13 +47,13 @@ public class ColorFunctions
 	//---- interface ColorFunction --------------------------------------------
 
 	public interface ColorFunction {
-		void apply( float[] hsl );
+		void apply( float[] hsla );
 	}
 
 	//---- class HSLIncreaseDecrease ------------------------------------------
 
 	/**
-	 * Increase or decrease hue, saturation or luminance of a color in the HSL color space
+	 * Increase or decrease hue, saturation, luminance or alpha of a color in the HSL color space
 	 * by an absolute or relative amount.
 	 */
 	public static class HSLIncreaseDecrease
@@ -75,18 +76,45 @@ public class ColorFunctions
 		}
 
 		@Override
-		public void apply( float[] hsl ) {
+		public void apply( float[] hsla ) {
 			float amount2 = increase ? amount : -amount;
-			amount2 = autoInverse && shouldInverse( hsl ) ? -amount2 : amount2;
-			hsl[hslIndex] = clamp( relative
-				? (hsl[hslIndex] * ((100 + amount2) / 100))
-				: (hsl[hslIndex] + amount2) );
+
+			if( hslIndex == 0 ) {
+				// hue is range 0-360
+				hsla[0] = (hsla[0] + amount2) % 360;
+				return;
+			}
+
+			amount2 = autoInverse && shouldInverse( hsla ) ? -amount2 : amount2;
+			hsla[hslIndex] = clamp( relative
+				? (hsla[hslIndex] * ((100 + amount2) / 100))
+				: (hsla[hslIndex] + amount2) );
 		}
 
-		protected boolean shouldInverse( float[] hsl ) {
+		protected boolean shouldInverse( float[] hsla ) {
 			return increase
-				? hsl[hslIndex] >= 50
-				: hsl[hslIndex] < 50;
+				? hsla[hslIndex] >= 50
+				: hsla[hslIndex] < 50;
+		}
+	}
+
+	//---- class HSLIncreaseDecrease ------------------------------------------
+
+	/**
+	 * Set the alpha of a color.
+	 */
+	public static class Fade
+		implements ColorFunction
+	{
+		public final float amount;
+
+		public Fade( float amount ) {
+			this.amount = amount;
+		}
+
+		@Override
+		public void apply( float[] hsla ) {
+			hsla[3] = clamp( amount );
 		}
 	}
 }

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatDarkLaf.properties

@@ -237,11 +237,15 @@ Separator.foreground=#515151
 
 #---- Slider ----
 
+Slider.trackValueColor=#4A88C7
 Slider.trackColor=#646464
-Slider.thumbColor=#A6A6A6
+Slider.thumbColor=$Slider.trackValueColor
 Slider.tickColor=#888
-Slider.hoverColor=darken($Slider.thumbColor,15%,derived)
-Slider.disabledForeground=#4c5052
+Slider.focusedColor=fade($Component.focusColor,70%,derived)
+Slider.hoverThumbColor=darken($Slider.thumbColor,10%,derived)
+Slider.pressedThumbColor=darken($Slider.thumbColor,15%,derived)
+Slider.disabledTrackColor=#4c5052
+Slider.disabledThumbColor=$Slider.disabledTrackColor
 
 
 #---- SplitPane ----

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties

@@ -506,8 +506,9 @@ Separator.stripeIndent=1
 #---- Slider ----
 
 Slider.focusInsets=0,0,0,0
-Slider.trackWidth=3
-Slider.thumbWidth=11
+Slider.trackWidth=2
+Slider.thumbSize=12,12
+Slider.focusWidth=4
 
 
 #---- Spinner ----
@@ -681,7 +682,7 @@ TitlePane.foreground=@foreground
 TitlePane.inactiveForeground=@disabledText
 
 TitlePane.closeHoverBackground=#e81123
-TitlePane.closePressedBackground=rgba($TitlePane.closeHoverBackground,60%)
+TitlePane.closePressedBackground=fade($TitlePane.closeHoverBackground,60%)
 TitlePane.closeHoverForeground=#fff
 TitlePane.closePressedForeground=#fff
 

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLightLaf.properties

@@ -249,11 +249,15 @@ Separator.foreground=#d1d1d1
 
 #---- Slider ----
 
+Slider.trackValueColor=#1E82E6
 Slider.trackColor=#c4c4c4
-Slider.thumbColor=#6e6e6e
+Slider.thumbColor=$Slider.trackValueColor
 Slider.tickColor=#888
-Slider.hoverColor=lighten($Slider.thumbColor,15%,derived)
-Slider.disabledForeground=#c0c0c0
+Slider.focusedColor=fade($Component.focusColor,50%,derived)
+Slider.hoverThumbColor=lighten($Slider.thumbColor,10%,derived)
+Slider.pressedThumbColor=lighten($Slider.thumbColor,15%,derived)
+Slider.disabledTrackColor=#c0c0c0
+Slider.disabledThumbColor=$Slider.disabledTrackColor
 
 
 #---- SplitPane ----

flatlaf-core/src/main/resources/com/formdev/flatlaf/IntelliJTheme$ThemeLaf.properties

@@ -35,6 +35,11 @@ Button.default.hoverBorderColor=null
 HelpButton.hoverBorderColor=null
 
 
+#---- Slider ----
+
+Slider.focusedColor=fade($Component.focusColor,40%,derived)
+
+
 #---- ToggleButton ----
 
 ToggleButton.startBackground=$ToggleButton.background
@@ -60,6 +65,8 @@ ToggleButton.endBackground=$ToggleButton.background
 [Cobalt_2]CheckBox.icon.background=#002946
 [Cobalt_2]CheckBox.icon.checkmarkColor=#002946
 
+[Dark_purple]Slider.focusedColor=fade($Component.focusColor,70%,derived)
+
 [Dracula]ProgressBar.selectionBackground=#fff
 [Dracula]ProgressBar.selectionForeground=#fff
 
@@ -81,6 +88,15 @@ ToggleButton.endBackground=$ToggleButton.background
 [High_contrast]ToggleButton.disabledSelectedBackground=#444
 [High_contrast]ToggleButton.toolbar.selectedBackground=#fff
 
+[One_Dark]Slider.focusedColor=fade(#568af2,40%)
+
+[Solarized_Dark]Slider.focusedColor=fade($Component.focusColor,80%,derived)
+
+[vuesion-theme]Slider.trackValueColor=#ececee
+[vuesion-theme]Slider.trackColor=#303a45
+[vuesion-theme]Slider.thumbColor=#ececee
+[vuesion-theme]Slider.focusedColor=fade(#ececee,20%)
+
 
 # Material Theme UI Lite