avoid painting text with our rendering hints enabled to avoid antialiased text in some components if text antialiasing is disabled in system (issue #227)

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

@@ -352,7 +352,7 @@ public class FlatComboBoxUI
 			FlatUIUtils.paintParentBackground( g, c );
 
 		Graphics2D g2 = (Graphics2D) g;
-		FlatUIUtils.setRenderingHints( g2 );
+		Object[] oldRenderingHints = FlatUIUtils.setRenderingHints( g2 );
 
 		int width = c.getWidth();
 		int height = c.getHeight();
@@ -386,6 +386,9 @@ public class FlatComboBoxUI
 			g2.fill( new Rectangle2D.Float( lx, focusWidth, lw, height - 1 - (focusWidth * 2)) );
 		}
 
+		// avoid that the "current value" renderer is invoked with enabled antialiasing
+		FlatUIUtils.resetRenderingHints( g2, oldRenderingHints );
+
 		paint( g, c );
 	}
 

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

@@ -155,7 +155,7 @@ public class FlatProgressBarUI
 			? 0
 			: Math.min( UIScale.scale( this.arc ), horizontal ? height : width );
 
-		FlatUIUtils.setRenderingHints( (Graphics2D) g );
+		Object[] oldRenderingHints = FlatUIUtils.setRenderingHints( g );
 
 		// paint track
 		RoundRectangle2D.Float trackShape = new RoundRectangle2D.Float( x, y, width, height, arc, arc );
@@ -163,6 +163,7 @@ public class FlatProgressBarUI
 		((Graphics2D)g).fill( trackShape );
 
 		// paint progress
+		int amountFull = 0;
 		if( progressBar.isIndeterminate() ) {
 			boxRect = getBox( boxRect );
 			if( boxRect != null ) {
@@ -170,11 +171,8 @@ public class FlatProgressBarUI
 				((Graphics2D)g).fill( new RoundRectangle2D.Float( boxRect.x, boxRect.y,
 					boxRect.width, boxRect.height, arc, arc ) );
 			}
-
-			if( progressBar.isStringPainted() )
-				paintString( g, x, y, width, height, 0, insets );
 		} else {
-			int amountFull = getAmountFull( insets, width, height );
+			amountFull = getAmountFull( insets, width, height );
 
 			RoundRectangle2D.Float progressShape = horizontal
 				? new RoundRectangle2D.Float( c.getComponentOrientation().isLeftToRight() ? x : x + (width - amountFull),
@@ -189,10 +187,12 @@ public class FlatProgressBarUI
 				((Graphics2D)g).fill( area );
 			} else
 				((Graphics2D)g).fill( progressShape );
-
-			if( progressBar.isStringPainted() )
-				paintString( g, x, y, width, height, amountFull, insets );
 		}
+
+		FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
+
+		if( progressBar.isStringPainted() )
+			paintString( g, x, y, width, height, amountFull, insets );
 	}
 
 	@Override

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

@@ -94,6 +94,8 @@ public class FlatSliderUI
 	protected boolean thumbHover;
 	protected boolean thumbPressed;
 
+	private Object[] oldRenderingHints;
+
 	public static ComponentUI createUI( JComponent c ) {
 		return new FlatSliderUI();
 	}
@@ -211,7 +213,7 @@ public class FlatSliderUI
 
 	@Override
 	public void paint( Graphics g, JComponent c ) {
-		FlatUIUtils.setRenderingHints( (Graphics2D) g );
+		oldRenderingHints = FlatUIUtils.setRenderingHints( g );
 
 /*debug
 		g.setColor( Color.gray );
@@ -227,6 +229,16 @@ public class FlatSliderUI
 debug*/
 
 		super.paint( g, c );
+
+		FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
+		oldRenderingHints = null;
+	}
+
+	@Override
+	public void paintLabels( Graphics g ) {
+		FlatUIUtils.runWithoutRenderingHints( g, oldRenderingHints, () -> {
+			super.paintLabels( g );
+		} );
 	}
 
 	@Override

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

@@ -226,6 +226,8 @@ public class FlatTabbedPaneUI
 	private boolean rolloverTabClose;
 	private boolean pressedTabClose;
 
+	private Object[] oldRenderingHints;
+
 	public static ComponentUI createUI( JComponent c ) {
 		return new FlatTabbedPaneUI();
 	}
@@ -791,9 +793,12 @@ public class FlatTabbedPaneUI
 
 	@Override
 	public void update( Graphics g, JComponent c ) {
-		FlatUIUtils.setRenderingHints( (Graphics2D) g );
+		oldRenderingHints = FlatUIUtils.setRenderingHints( g );
 
 		super.update( g, c );
+
+		FlatUIUtils.resetRenderingHints( g, oldRenderingHints );
+		oldRenderingHints = null;
 	}
 
 	@Override
@@ -874,27 +879,29 @@ public class FlatTabbedPaneUI
 	{
 		g.setFont( font );
 
-		// html
-		View view = getTextViewForTab( tabIndex );
-		if( view != null ) {
-			view.paint( g, textRect );
-			return;
-		}
+		FlatUIUtils.runWithoutRenderingHints( g, oldRenderingHints, () -> {
+			// html
+			View view = getTextViewForTab( tabIndex );
+			if( view != null ) {
+				view.paint( g, textRect );
+				return;
+			}
 
-		// plain text
-		Color color;
-		if( tabPane.isEnabled() && tabPane.isEnabledAt( tabIndex ) ) {
-			color = tabPane.getForegroundAt( tabIndex );
-			if( isSelected && (color instanceof UIResource) && selectedForeground != null )
-				color = selectedForeground;
-		} else
-			color = disabledForeground;
+			// plain text
+			Color color;
+			if( tabPane.isEnabled() && tabPane.isEnabledAt( tabIndex ) ) {
+				color = tabPane.getForegroundAt( tabIndex );
+				if( isSelected && (color instanceof UIResource) && selectedForeground != null )
+					color = selectedForeground;
+			} else
+				color = disabledForeground;
 
-		int mnemIndex = FlatLaf.isShowMnemonics() ? tabPane.getDisplayedMnemonicIndexAt( tabIndex ) : -1;
+			int mnemIndex = FlatLaf.isShowMnemonics() ? tabPane.getDisplayedMnemonicIndexAt( tabIndex ) : -1;
 
-		g.setColor( color );
-		FlatUIUtils.drawStringUnderlineCharAt( tabPane, g, title, mnemIndex,
-			textRect.x, textRect.y + metrics.getAscent() );
+			g.setColor( color );
+			FlatUIUtils.drawStringUnderlineCharAt( tabPane, g, title, mnemIndex,
+				textRect.x, textRect.y + metrics.getAscent() );
+		} );
 	}
 
 	@Override

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

@@ -116,7 +116,6 @@ public class FlatToolTipUI
 			FontMetrics fm = c.getFontMetrics( c.getFont() );
 			Insets insets = c.getInsets();
 
-			FlatUIUtils.setRenderingHints( (Graphics2D) g );
 			g.setColor( c.getForeground() );
 
 			List<String> lines = StringUtils.split( ((JToolTip)c).getTipText(), '\n' );

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

@@ -240,10 +240,57 @@ public class FlatUIUtils
 	/**
 	 * Sets rendering hints used for painting.
 	 */
-	public static void setRenderingHints( Graphics2D g ) {
-		g.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
-		g.setRenderingHint( RenderingHints.KEY_STROKE_CONTROL,
+	public static Object[] setRenderingHints( Graphics g ) {
+		Graphics2D g2 = (Graphics2D) g;
+		Object[] oldRenderingHints = new Object[] {
+			g2.getRenderingHint( RenderingHints.KEY_ANTIALIASING ),
+			g2.getRenderingHint( RenderingHints.KEY_STROKE_CONTROL ),
+		};
+
+		g2.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
+		g2.setRenderingHint( RenderingHints.KEY_STROKE_CONTROL,
 			MAC_USE_QUARTZ ? RenderingHints.VALUE_STROKE_PURE : RenderingHints.VALUE_STROKE_NORMALIZE );
+
+		return oldRenderingHints;
+	}
+
+	/**
+	 * Resets rendering hints previously set with {@link #setRenderingHints(Graphics2D)}.
+	 */
+	public static void resetRenderingHints( Graphics g, Object[] oldRenderingHints ) {
+		Graphics2D g2 = (Graphics2D) g;
+		g2.setRenderingHint( RenderingHints.KEY_ANTIALIASING, oldRenderingHints[0] );
+		g2.setRenderingHint( RenderingHints.KEY_STROKE_CONTROL, oldRenderingHints[1] );
+	}
+
+	/**
+	 * Temporary resets rendering hints set with {@link #setRenderingHints(Graphics2D)}
+	 * and runs the given runnable.
+	 * <p>
+	 * This is intended for painting text while rendering hints are set.
+	 * <p>
+	 * If text antialiasing is disabled (in OS system settings or via
+	 * {@code -Dawt.useSystemAAFontSettings=off}), but general antialiasing is enabled,
+	 * then text is still painted using some kind of "grayscale" antialiasing,
+	 * which may make the text look bold (depends on font and font size).
+	 * To avoid this, temporary disable general antialiasing.
+	 * This does not affect text rendering if text antialiasing is enabled (usually the default).
+	 */
+	public static void runWithoutRenderingHints( Graphics g, Object[] oldRenderingHints, Runnable runnable ) {
+		if( oldRenderingHints == null ) {
+			runnable.run();
+			return;
+		}
+
+		Graphics2D g2 = (Graphics2D) g;
+		Object[] oldRenderingHints2 = new Object[] {
+			g2.getRenderingHint( RenderingHints.KEY_ANTIALIASING ),
+			g2.getRenderingHint( RenderingHints.KEY_STROKE_CONTROL ),
+		};
+
+		resetRenderingHints( g2, oldRenderingHints );
+		runnable.run();
+		resetRenderingHints( g2, oldRenderingHints2 );
 	}
 
 	public static Color deriveColor( Color color, Color baseColor ) {