change functionality to utilize FileFormat changes of PR1828

Author: Michael5601

bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/graphics/ImageData.java

@@ -361,10 +361,8 @@ public ImageData(InputStream stream) {
  * code is still responsible for closing the input stream.
  *
  * @param stream the input stream to load the image from (must not be null)
- * @param zoom the zoom factor to apply when rasterizing an SVG.
- *
- * A value of 0 means that the standard method for loading should be used.
- * This case is equivalent to calling {@link ImageLoader#load(InputStream)}.
+ * @param fileZoom the zoom of the file from which the <code>ImageData</code> is loaded
+ * @param targetZoom the zoom for the returned <code>ImageData</code> (must be grater than 0)
  *
  * A value above 0 specifies a scaling factor for the output image. For example:
  * <ul>
@@ -386,10 +384,8 @@ public ImageData(InputStream stream) {
  * @see ImageLoader#load(InputStream)
  * @since 3.130
  */
-public ImageData(InputStream stream, int zoom) {
-	ImageData[] data = ImageDataLoader.load(stream, zoom);
-	if (data.length < 1) SWT.error(SWT.ERROR_INVALID_IMAGE);
-	ImageData i = data[0];
+public ImageData(InputStream stream, int fileZoom, int targetZoom) {
+	ImageData i = ImageDataLoader.load(stream, fileZoom, targetZoom).element();
 	setAllFields(
 		i.width,
 		i.height,
@@ -462,9 +458,8 @@ public ImageData(String filename) {
  * image, or if the image has an unsupported type.
  *
  * @param filename the name of the file to load the image from (must not be null)
- * @param zoom the zoom factor to apply when rasterizing a SVG.
- * A value of 0 means that the standard method for loading should be used.
- * This case is equivalent to calling {@link ImageLoader#load(String)}.
+ * @param fileZoom the zoom of the file from which the <code>ImageData</code> is loaded
+ * @param targetZoom the zoom for the returned <code>ImageData</code> (must be grater than 0)
  *
  * A value above 0 specifies a scaling factor for the output image. For example:
  * <ul>
@@ -485,10 +480,8 @@ public ImageData(String filename) {
  *
  * @since 3.130
  */
-public ImageData(String filename, int zoom) {
-	ImageData[] data = ImageDataLoader.load(filename, zoom);
-	if (data.length < 1) SWT.error(SWT.ERROR_INVALID_IMAGE);
-	ImageData i = data[0];
+public ImageData(String filename, int fileZoom, int targetZoom) {
+	ImageData i = ImageDataLoader.load(filename, fileZoom, targetZoom).element();
 	setAllFields(
 		i.width,
 		i.height,

bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/FileFormat.java

@@ -53,6 +53,9 @@ public abstract class FileFormat {
 		try {
 			FORMAT_FACTORIES.add(OS2BMPFileFormat::new);
 		} catch (NoClassDefFoundError e) { } // ignore format
+		try {
+			FORMAT_FACTORIES.add(SVGFileFormat::new);
+		} catch (NoClassDefFoundError e) { } // ignore format
 	}
 
 	public static final int DEFAULT_ZOOM = 100;
@@ -84,6 +87,16 @@ List<ElementAtZoom<ImageData>> loadFromByteStream(int fileZoom, int targetZoom)
 		}
 	}
 
+	static abstract class DynamicImageFileFormat extends FileFormat {
+
+		abstract ImageData[] loadFromByteStream(int targetZoom);
+
+		@Override
+		List<ElementAtZoom<ImageData>> loadFromByteStream(int fileZoom, int targetZoom) {
+			return Arrays.stream(loadFromByteStream(targetZoom)).map(d -> new ElementAtZoom<>(d, fileZoom)).toList();
+		}
+	}
+
 	LEDataInputStream inputStream;
 	LEDataOutputStream outputStream;
 	ImageLoader loader;

bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/SVGFileFormat.java

@@ -0,0 +1,53 @@
+/*******************************************************************************
+ * Copyright (c) 2025 Vector Informatik GmbH and others.
+ *
+ * This program and the accompanying materials are made available under the terms of the Eclipse
+ * Public License 2.0 which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors: Michael Bangas (Vector Informatik GmbH) - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.swt.internal.image;
+
+import java.io.*;
+import java.nio.charset.*;
+import java.util.*;
+
+import org.eclipse.swt.*;
+import org.eclipse.swt.graphics.*;
+import org.eclipse.swt.internal.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
+
+public class SVGFileFormat extends DynamicImageFileFormat {
+
+	/** The instance of the registered {@link SVGRasterizer}. */
+	private static final SVGRasterizer RASTERIZER = ServiceLoader.load(SVGRasterizer.class).findFirst().orElse(null);
+
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
+		byte[] firstBytes = new byte[5];
+	    int bytesRead = stream.read(firstBytes);
+	    stream.unread(firstBytes);
+	    String header = new String(firstBytes, 0, bytesRead, StandardCharsets.UTF_8).trim();
+	    return header.startsWith("<?xml") || header.startsWith("<svg");
+	}
+
+	@Override
+	ImageData[] loadFromByteStream(int targetZoom) {
+		try {
+			if (RASTERIZER != null && targetZoom != 0) {
+				return RASTERIZER.rasterizeSVG(inputStream, targetZoom);
+			}
+		} catch (IOException e) {
+			SWT.error(SWT.ERROR_INVALID_IMAGE, e);
+		}
+		return null;
+	}
+
+	@Override
+	void unloadIntoByteStream(ImageLoader loader) {
+		throw new UnsupportedOperationException();
+	}
+}