Extract GC related operation in TextUtilities and FigureUtilities to be Drawable aware

akoch-yatta · akoch-yatta · commit c21bea1ee1f0 · 2025-09-08T15:15:52.000+02:00
This commit introduces two new utility classes to fully replace
TextUtilities and partially replace FigureUtilities, when calculations
on a GC are involded. Therefor DrawableTextUtilities or DrawableFigureUtilities
can to be instantiated with a Drawable passed as context when a GC is
instantiated.
diff --git a/org.eclipse.draw2d/src/org/eclipse/draw2d/DrawableFigureUtilities.java b/org.eclipse.draw2d/src/org/eclipse/draw2d/DrawableFigureUtilities.java
@@ -0,0 +1,146 @@
+/*******************************************************************************
+ * Copyright (c) 2025 Yatta and others.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Yatta - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.draw2d;
+
+import org.eclipse.swt.graphics.Drawable;
+import org.eclipse.swt.graphics.Font;
+import org.eclipse.swt.graphics.FontMetrics;
+import org.eclipse.swt.graphics.GC;
+
+import org.eclipse.draw2d.geometry.Dimension;
+
+/**
+ * Provides miscellaneous Figure operations calculated with the zoom context of
+ * the the provided {@code Drawable}.
+ *
+ * All GC related operations are mirrored from {@code FigureUtilities}
+ *
+ * @since 3.27
+ */
+public class DrawableFigureUtilities {
+	private final GC gc;
+	private Font appliedFont;
+	private FontMetrics metrics;
+
+	public DrawableFigureUtilities(Drawable source) {
+		gc = new GC(source);
+		appliedFont = gc.getFont();
+	}
+
+	/**
+	 * Returns the FontMetrics associated with the passed Font.
+	 *
+	 * @param f the font
+	 * @return the FontMetrics for the given font
+	 * @see GC#getFontMetrics()
+	 * @since 3.27
+	 */
+	public FontMetrics getFontMetrics(Font f) {
+		setFont(f);
+		if (metrics == null) {
+			metrics = gc.getFontMetrics();
+		}
+		return metrics;
+	}
+
+	/**
+	 * Returns the dimensions of the String <i>s</i> using the font <i>f</i>. Tab
+	 * expansion and carriage return processing are performed.
+	 *
+	 * @param s the string
+	 * @param f the font
+	 * @return the text's dimensions
+	 * @see GC#textExtent(String)
+	 * @since 3.27
+	 */
+	protected org.eclipse.swt.graphics.Point getTextDimension(String s, Font f) {
+		setFont(f);
+		return gc.textExtent(s);
+	}
+
+	/**
+	 * Returns the dimensions of the String <i>s</i> using the font <i>f</i>. No tab
+	 * expansion or carriage return processing will be performed.
+	 *
+	 * @param s the string
+	 * @param f the font
+	 * @return the string's dimensions
+	 * @see GC#stringExtent(java.lang.String)
+	 * @since 3.27
+	 */
+	protected org.eclipse.swt.graphics.Point getStringDimension(String s, Font f) {
+		setFont(f);
+		return gc.stringExtent(s);
+	}
+
+	/**
+	 * Returns the Dimensions of the given text, converting newlines and tabs
+	 * appropriately.
+	 *
+	 * @param text the text
+	 * @param f    the font
+	 * @return the dimensions of the given text
+	 * @since 3.27
+	 */
+	public Dimension getTextExtents(String text, Font f) {
+		return new Dimension(getTextDimension(text, f));
+	}
+
+	/**
+	 * Returns the Dimensions of <i>s</i> in Font <i>f</i>.
+	 *
+	 * @param s the string
+	 * @param f the font
+	 * @return the dimensions of the given string
+	 * @since 3.27
+	 */
+	public Dimension getStringExtents(String s, Font f) {
+		return new Dimension(getStringDimension(s, f));
+	}
+
+	/**
+	 * Returns the Dimensions of the given text, converting newlines and tabs
+	 * appropriately.
+	 *
+	 * @param s      the string
+	 * @param f      the font
+	 * @param result the Dimension that will contain the result of this calculation
+	 * @since 3.27
+	 */
+	public void getTextExtents(String s, Font f, Dimension result) {
+		org.eclipse.swt.graphics.Point pt = getTextDimension(s, f);
+		result.width = pt.x;
+		result.height = pt.y;
+	}
+
+	/**
+	 * Returns the width of <i>s</i> in Font <i>f</i>.
+	 *
+	 * @param s the string
+	 * @param f the font
+	 * @return the width
+	 * @since 3.27
+	 */
+	public int getTextWidth(String s, Font f) {
+		return getTextDimension(s, f).x;
+	}
+
+	private void setFont(Font f) {
+		if (appliedFont == f || (f != null && f.equals(appliedFont))) {
+			return;
+		}
+		gc.setFont(f);
+		appliedFont = f;
+		metrics = null;
+	}
+}
diff --git a/org.eclipse.draw2d/src/org/eclipse/draw2d/DrawableTextUtilities.java b/org.eclipse.draw2d/src/org/eclipse/draw2d/DrawableTextUtilities.java
@@ -0,0 +1,83 @@
+/*******************************************************************************
+ * Copyright (c) 2025 Yatta and others.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Yatta - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.draw2d;
+
+import org.eclipse.swt.graphics.Drawable;
+import org.eclipse.swt.graphics.Font;
+import org.eclipse.swt.graphics.FontMetrics;
+
+import org.eclipse.draw2d.geometry.Dimension;
+
+/**
+ * Provides miscellaneous text operations calculated with the zoom context of
+ * the the provided {@code Drawable}.
+ *
+ * @since 3.27
+ */
+public class DrawableTextUtilities extends TextUtilities {
+
+	private final DrawableFigureUtilities figureUtilities;
+
+	public DrawableTextUtilities(Drawable source) {
+		figureUtilities = new DrawableFigureUtilities(source);
+	}
+
+	/**
+	 * Returns the Dimensions of <i>s</i> in Font <i>f</i>.
+	 *
+	 * @param s the string
+	 * @param f the font
+	 * @return the dimensions of the given string
+	 */
+	@Override
+	public Dimension getStringExtents(String s, Font f) {
+		return figureUtilities.getStringExtents(s, f);
+	}
+
+	/**
+	 * Returns the Dimensions of the given text, converting newlines and tabs
+	 * appropriately.
+	 *
+	 * @param s the text
+	 * @param f the font
+	 * @return the dimensions of the given text
+	 */
+	@Override
+	public Dimension getTextExtents(String s, Font f) {
+		return figureUtilities.getTextExtents(s, f);
+	}
+
+	/**
+	 * Gets the font's ascent.
+	 *
+	 * @param font
+	 * @return the font's ascent
+	 */
+	@Override
+	public int getAscent(Font font) {
+		FontMetrics fm = figureUtilities.getFontMetrics(font);
+		return fm.getHeight() - fm.getDescent();
+	}
+
+	/**
+	 * Gets the font's descent.
+	 *
+	 * @param font
+	 * @return the font's descent
+	 */
+	@Override
+	public int getDescent(Font font) {
+		return figureUtilities.getFontMetrics(font).getDescent();
+	}
+}
diff --git a/org.eclipse.gef/src/org/eclipse/gef/ui/palette/FlyoutPaletteComposite.java b/org.eclipse.gef/src/org/eclipse/gef/ui/palette/FlyoutPaletteComposite.java
@@ -73,6 +73,7 @@
 import org.eclipse.draw2d.ButtonBorder;
 import org.eclipse.draw2d.ColorConstants;
 import org.eclipse.draw2d.Cursors;
+import org.eclipse.draw2d.DrawableTextUtilities;
 import org.eclipse.draw2d.FocusEvent;
 import org.eclipse.draw2d.FocusListener;
 import org.eclipse.draw2d.Graphics;
@@ -81,6 +82,7 @@
 import org.eclipse.draw2d.LightweightSystem;
 import org.eclipse.draw2d.MarginBorder;
 import org.eclipse.draw2d.PositionConstants;
+import org.eclipse.draw2d.TextUtilities;
 import org.eclipse.draw2d.Triangle;
 import org.eclipse.draw2d.geometry.Dimension;
 
@@ -1114,6 +1116,7 @@ protected void updateState() {
 	private class TitleLabel extends Label {
 		protected static final Border BORDER = new MarginBorder(4, 3, 4, 3);
 		protected static final Border TOOL_TIP_BORDER = new MarginBorder(0, 2, 0, 2);
+		private TextUtilities textUtilities;
 
 		public TitleLabel(boolean isHorizontal) {
 			super(GEFMessages.Palette_Label, InternalImages.get(InternalImages.IMG_PALETTE));
@@ -1125,6 +1128,14 @@ public TitleLabel(boolean isHorizontal) {
 			setForegroundColor(ColorConstants.listForeground);
 		}
 
+		@Override
+		public TextUtilities getTextUtilities() {
+			if (textUtilities == null) {
+				textUtilities = new DrawableTextUtilities(paletteContainer);
+			}
+			return textUtilities;
+		}
+
 		@Override
 		public IFigure getToolTip() {
 			if (isTextTruncated()) {
diff --git a/org.eclipse.gef/src/org/eclipse/gef/ui/palette/editparts/PaletteEditPart.java b/org.eclipse.gef/src/org/eclipse/gef/ui/palette/editparts/PaletteEditPart.java
@@ -21,17 +21,21 @@
 import java.util.List;
 import java.util.Map;
 
+import org.eclipse.swt.graphics.Drawable;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.widgets.Display;
 
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.ui.IMemento;
 
 import org.eclipse.draw2d.Border;
+import org.eclipse.draw2d.DrawableTextUtilities;
 import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.MarginBorder;
+import org.eclipse.draw2d.TextUtilities;
 import org.eclipse.draw2d.geometry.Dimension;
 import org.eclipse.draw2d.text.FlowPage;
+import org.eclipse.draw2d.text.FlowUtilities;
 import org.eclipse.draw2d.text.TextFlow;
 
 import org.eclipse.gef.AccessibleEditPart;
@@ -46,6 +50,7 @@
 import org.eclipse.gef.ui.palette.PaletteMessages;
 import org.eclipse.gef.ui.palette.PaletteViewer;
 import org.eclipse.gef.ui.palette.PaletteViewerPreferences;
+import org.eclipse.gef.util.EditPartUtilities;
 
 /**
  * The abstract implementation of palette edit parts. All edit parts used in the
@@ -129,12 +134,36 @@ public Dimension getPreferredSize(int w, int h) {
 		};
 		fp.setOpaque(true);
 		fp.setBorder(TOOLTIP_BORDER);
-		TextFlow tf = new TextFlow();
+		TextFlow tf = new PaletteTooltipTextFlow(EditPartUtilities.getMainControl(this).getShell());
 		tf.setText(message);
 		fp.add(tf);
 		return fp;
 	}
 
+	private class PaletteTooltipTextFlow extends TextFlow {
+
+		private final TextUtilities textUtilities;
+
+		private PaletteTooltipTextFlow(Drawable drawable) {
+			textUtilities = new DrawableTextUtilities(drawable);
+		}
+
+		@Override
+		protected FlowUtilities getFlowUtilities() {
+			return new FlowUtilities() {
+				@Override
+				protected TextUtilities getTextUtilities() {
+					return textUtilities;
+				}
+			};
+		}
+
+		@Override
+		protected TextUtilities getTextUtilities() {
+			return textUtilities;
+		}
+	}
+
 	/**
 	 * @see org.eclipse.gef.editparts.AbstractGraphicalEditPart#deactivate()
 	 */
diff --git a/org.eclipse.gef/src/org/eclipse/gef/util/EditPartUtilities.java b/org.eclipse.gef/src/org/eclipse/gef/util/EditPartUtilities.java
@@ -16,6 +16,8 @@
 import java.util.HashSet;
 import java.util.LinkedHashSet;
 
+import org.eclipse.swt.widgets.Control;
+
 import org.eclipse.gef.ConnectionEditPart;
 import org.eclipse.gef.EditPart;
 import org.eclipse.gef.GraphicalEditPart;
@@ -86,4 +88,8 @@ public static HashSet<? extends ConnectionEditPart> getNestedConnectionEditParts
 		});
 		return edges;
 	}
+
+	public static Control getMainControl(EditPart editPart) {
+		return editPart.getRoot().getViewer().getControl().getShell();
+	}
 }
