Theme Editor: paint real colors and HSL values in overlay on right side of editor (instead of behind editor text; previous commit)

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemeEditorOverlay.java

@@ -0,0 +1,136 @@
+/*
+ * Copyright 2020 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.themeeditor;
+
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.FontMetrics;
+import java.awt.Graphics;
+import java.awt.Point;
+import java.awt.Rectangle;
+import javax.swing.JComponent;
+import javax.swing.JLayer;
+import javax.swing.plaf.LayerUI;
+import javax.swing.text.BadLocationException;
+import org.fife.ui.rsyntaxtextarea.Token;
+import com.formdev.flatlaf.UIDefaultsLoaderAccessor;
+import com.formdev.flatlaf.ui.FlatUIUtils;
+import com.formdev.flatlaf.util.HSLColor;
+import com.formdev.flatlaf.util.UIScale;
+
+/**
+ * An overlay layer that paints additional information about line content on the right side.
+ *
+ * @author Karl Tauber
+ */
+class FlatThemeEditorOverlay
+	extends LayerUI<FlatSyntaxTextArea>
+{
+	private static final int COLOR_PREVIEW_WIDTH = 100;
+
+	private Font font;
+	private Font baseFont;
+
+	@Override
+	public void paint( Graphics g, JComponent c ) {
+		// paint the syntax text area
+		super.paint( g, c );
+
+		@SuppressWarnings( "unchecked" )
+		FlatSyntaxTextArea textArea = ((JLayer<FlatSyntaxTextArea>)c).getView();
+		Rectangle clipBounds = g.getClipBounds();
+
+		// determine first and last visible lines
+		int firstVisibleLine;
+		int lastVisibleLine;
+		try {
+			int startOffset = textArea.viewToModel( new Point( 0, clipBounds.y ) );
+			int endOffset = textArea.viewToModel( new Point( 0, clipBounds.y + clipBounds.height ) );
+			firstVisibleLine = textArea.getLineOfOffset( startOffset );
+			lastVisibleLine = textArea.getLineOfOffset( endOffset );
+		} catch( BadLocationException ex ) {
+			// ignore
+			return;
+		}
+
+		// compute font (and cache it)
+		if( baseFont != textArea.getFont() ) {
+			baseFont = textArea.getFont();
+			int fontSize = Math.max( (int) Math.round( baseFont.getSize() * 0.8 ), 8 );
+			font = baseFont.deriveFont( (float) fontSize );
+		}
+
+		FontMetrics fm = c.getFontMetrics( font );
+		int maxTextWidth = fm.stringWidth( "HSL 360 100 100" );
+		int textHeight = fm.getAscent() - fm.getLeading();
+
+		int width = c.getWidth();
+		int previewWidth = UIScale.scale( COLOR_PREVIEW_WIDTH );
+		int gap = UIScale.scale( 4 );
+
+		// check whether preview is outside of clip bounds
+		if( clipBounds.x + clipBounds.width < width - previewWidth - maxTextWidth - gap )
+			return;
+
+		g.setFont( font );
+
+		// paint additional information
+		for( int line = firstVisibleLine; line <= lastVisibleLine; line++ ) {
+			Color color = getColorInLine( textArea, line );
+			if( color == null )
+				continue;
+
+			try {
+				// paint color preview
+				int lineEndOffset = textArea.getLineEndOffset( line );
+				Rectangle r = textArea.modelToView( lineEndOffset - 1 );
+				int pw = Math.min( width - r.x - gap, previewWidth );
+				int px = width - pw;
+				g.setColor( color );
+				g.fillRect( px, r.y, pw, r.height );
+
+				// paint text
+				int textX = px - maxTextWidth;
+				if( textX > r.x + gap) {
+					float[] hsl = HSLColor.fromRGB( color );
+					String hslStr = String.format( "HSL %d %d %d",
+						Math.round( hsl[0] ), Math.round( hsl[1] ), Math.round( hsl[2] ) );
+					g.setColor( textArea.getForeground() );
+					FlatUIUtils.drawString( textArea, g, hslStr, textX,
+						r.y + ((r.height - textHeight) / 2) + textHeight );
+				}
+			} catch( BadLocationException ex ) {
+				// ignore
+			}
+		}
+	}
+
+	private Color getColorInLine( FlatSyntaxTextArea textArea, int line ) {
+		Token token = textArea.getTokenListForLine( line );
+		for( Token t = token; t != null && t.isPaintable(); t = t.getNextToken() ) {
+			if( t.getType() == FlatThemeTokenMaker.TOKEN_COLOR ) {
+				try {
+					return new Color( UIDefaultsLoaderAccessor.parseColorRGBA( t.getLexeme() ), true );
+				} catch( IllegalArgumentException ex ) {
+					break;
+				}
+			}
+		}
+
+		return null;
+	}
+}

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemeEditorPane.java

@@ -21,6 +21,7 @@ import java.awt.Color;
 import java.awt.Font;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import javax.swing.JLayer;
 import javax.swing.JPanel;
 import org.fife.ui.rsyntaxtextarea.AbstractTokenMakerFactory;
 import org.fife.ui.rsyntaxtextarea.FileLocation;
@@ -55,7 +56,7 @@ class FlatThemeEditorPane
 		textArea.setSyntaxEditingStyle( FLATLAF_STYLE );
 		textArea.setMarkOccurrences( true );
 		textArea.addParser( new FlatThemeParser() );
-		textArea.setUseColorOfColorTokens( true );
+//		textArea.setUseColorOfColorTokens( true );
 
 		// theme
 		try {
@@ -71,15 +72,19 @@ class FlatThemeEditorPane
 		scheme.getStyle( FlatThemeTokenMaker.TOKEN_COLOR ).background = new Color( 0x0a000000, true );
 		scheme.getStyle( FlatThemeTokenMaker.TOKEN_VARIABLE ).background = new Color( 0x1800cc00, true );
 
+		// create overlay layer
+		JLayer<FlatSyntaxTextArea> overlay = new JLayer<>( textArea, new FlatThemeEditorOverlay() );
+
 		// create scroll pane
-		scrollPane = new RTextScrollPane( textArea );
+		scrollPane = new RTextScrollPane( overlay );
 		scrollPane.setLineNumbersEnabled( true );
 
 		// scale fonts
-		if( UIScale.getUserScaleFactor() != 1 ) {
+		if( UIScale.getUserScaleFactor() != 1 )
 			textArea.setFont( scaleFont( textArea.getFont() ) );
-			scrollPane.getGutter().setLineNumberFont( scaleFont( scrollPane.getGutter().getLineNumberFont() ) );
-		}
+
+		// use same font for line numbers as in editor
+		scrollPane.getGutter().setLineNumberFont( textArea.getFont() );
 
 		add( scrollPane, BorderLayout.CENTER );
 	}