Prepare the implementation of dynamic image file-formats

Required for
- #1638

Author: HannesWell

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

@@ -54,27 +54,47 @@ public abstract class FileFormat {
 		} catch (NoClassDefFoundError e) { } // ignore format
 	}
 
+	public static final int STATIC_ZOOM_FACTOR = 100;
+
+	static abstract class StaticFileFormat extends FileFormat {
+
+		abstract ImageData[] loadFromByteStream();
+
+		@Override
+		ImageData[] loadFromByteStream(int zoom) {
+			if (zoom == STATIC_ZOOM_FACTOR) {
+				return loadFromByteStream();
+			}
+			return Arrays.stream(loadFromByteStream()) //
+					.map(d -> {
+						int width = (int) Math.round(d.width * zoom / 100.);
+						int height = (int) Math.round(d.height * zoom / 100.);
+						return d.scaledTo(width, height);
+					}).toArray(ImageData[]::new);
+		}
+	}
+
 	LEDataInputStream inputStream;
 	LEDataOutputStream outputStream;
 	ImageLoader loader;
 	int compression;
 
-/**
- * Return whether or not the specified input stream
- * represents a supported file format.
- */
-abstract boolean isFileFormat(LEDataInputStream stream);
+	/**
+	 * Return whether or not the specified input stream represents a supported file
+	 * format.
+	 */
+	abstract boolean isFileFormat(LEDataInputStream stream) throws IOException;
 
-abstract ImageData[] loadFromByteStream();
+	abstract ImageData[] loadFromByteStream(int zoom);
 
 /**
  * Read the specified input stream, and return the
  * device independent image array represented by the stream.
  */
-public ImageData[] loadFromStream(LEDataInputStream stream) {
+public ImageData[] loadFromStream(LEDataInputStream stream, int zoom) {
 	try {
 		inputStream = stream;
-		return loadFromByteStream();
+		return loadFromByteStream(zoom);
 	} catch (Exception e) {
 		if (e instanceof IOException) {
 			SWT.error(SWT.ERROR_IO, e);
@@ -86,17 +106,23 @@ public ImageData[] loadFromStream(LEDataInputStream stream) {
 }
 
 /**
- * Read the specified input stream using the specified loader, and
- * return the device independent image array represented by the stream.
+ * Read the specified input stream using the specified loader, and return the
+ * device independent image array represented by the stream.
  */
-public static ImageData[] load(InputStream is, ImageLoader loader) {
+public static ImageData[] load(InputStream is, ImageLoader loader, int zoom) {
 	LEDataInputStream stream = new LEDataInputStream(is);
 	FileFormat fileFormat = FORMAT_FACTORIES.stream().skip(1) //
-			.map(Supplier::get).filter(f -> f.isFileFormat(stream)) //
+			.map(Supplier::get).filter(f -> {
+				try {
+					return f.isFileFormat(stream);
+				} catch (IOException e) {
+					return false;
+				}
+			}) //
 			.findFirst().orElse(null);
- 	if (fileFormat == null) SWT.error(SWT.ERROR_UNSUPPORTED_FORMAT);
+	if (fileFormat == null) SWT.error(SWT.ERROR_UNSUPPORTED_FORMAT);
 	fileFormat.loader = loader;
-	return fileFormat.loadFromStream(stream);
+return fileFormat.loadFromStream(stream, zoom);
 }
 
 /**

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

@@ -14,11 +14,13 @@
 package org.eclipse.swt.internal.image;
 
 
+import java.io.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
-import java.io.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
-public final class GIFFileFormat extends FileFormat {
+public final class GIFFileFormat extends StaticFileFormat {
 	String signature;
 	int screenWidth, screenHeight, backgroundPixel, bitsPerPixel, defaultDepth;
 	int disposalMethod = 0;
@@ -51,15 +53,11 @@ static PaletteData grayRamp(int numGrays) {
 	}
 
 	@Override
-	boolean isFileFormat(LEDataInputStream stream) {
-		try {
-			byte[] signature = new byte[3];
-			stream.read(signature);
-			stream.unread(signature);
-			return signature[0] == 'G' && signature[1] == 'I' && signature[2] == 'F';
-		} catch (Exception e) {
-			return false;
-		}
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
+		byte[] signature = new byte[3];
+		stream.read(signature);
+		stream.unread(signature);
+		return signature[0] == 'G' && signature[1] == 'I' && signature[2] == 'F';
 	}
 
 	/**

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

@@ -18,11 +18,13 @@
 package org.eclipse.swt.internal.image;
 
 
+import java.io.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
-import java.io.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
-public final class JPEGFileFormat extends FileFormat {
+public final class JPEGFileFormat extends StaticFileFormat {
 	int restartInterval;
 	JPEGFrameHeader frameHeader;
 	int imageWidth, imageHeight;
@@ -1362,16 +1364,14 @@ void inverseDCT(int[] dataUnit) {
 		}
 	}
 }
-@Override
-boolean isFileFormat(LEDataInputStream stream) {
-	try {
+
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
 		JPEGStartOfImage soi = new JPEGStartOfImage(stream);
 		stream.unread(soi.reference);
-		return soi.verify();  // we no longer check for appN
-	} catch (Exception e) {
-		return false;
+		return soi.verify(); // we no longer check for appN
 	}
-}
+
 boolean isZeroInColumn(int[] dataUnit, int col) {
 	return dataUnit[col + 8] == 0 && dataUnit[col + 16] == 0
 			&& dataUnit[col + 24] == 0 && dataUnit[col + 32] == 0

bundles/org.eclipse.swt/Eclipse SWT/common/org/eclipse/swt/internal/image/OS2BMPFileFormat.java

@@ -14,27 +14,26 @@
 package org.eclipse.swt.internal.image;
 
 
+import java.io.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
-import java.io.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
-public final class OS2BMPFileFormat extends FileFormat {
+public final class OS2BMPFileFormat extends StaticFileFormat {
 	static final int BMPFileHeaderSize = 14;
 	static final int BMPHeaderFixedSize = 12;
 	int width, height, bitCount;
 
-@Override
-boolean isFileFormat(LEDataInputStream stream) {
-	try {
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
 		byte[] header = new byte[18];
 		stream.read(header);
 		stream.unread(header);
 		int infoHeaderSize = (header[14] & 0xFF) | ((header[15] & 0xFF) << 8) | ((header[16] & 0xFF) << 16) | ((header[17] & 0xFF) << 24);
 		return header[0] == 0x42 && header[1] == 0x4D && infoHeaderSize == BMPHeaderFixedSize;
-	} catch (Exception e) {
-		return false;
 	}
-}
+
 byte[] loadData(byte[] infoHeader) {
 	int stride = (width * bitCount + 7) / 8;
 	stride = (stride + 3) / 4 * 4; // Round up to 4 byte multiple

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

@@ -19,8 +19,9 @@
 
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
-public final class PNGFileFormat extends FileFormat {
+public final class PNGFileFormat extends StaticFileFormat {
 	static final int SIGNATURE_LENGTH = 8;
 	static final int PRIME = 65521;
 	PngIhdrChunk headerChunk;
@@ -151,9 +152,9 @@ void unloadIntoByteStream(ImageLoader loader) {
 	PngEncoder encoder = new PngEncoder(loader);
 	encoder.encode(outputStream);
 }
-@Override
-boolean isFileFormat(LEDataInputStream stream) {
-	try {
+
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		stream.read(signature);
 		stream.unread(signature);
@@ -166,10 +167,8 @@ boolean isFileFormat(LEDataInputStream stream) {
 		if ((signature[6] & 0xFF) != 26) return false; //<CTRL/Z>
 		if ((signature[7] & 0xFF) != 10) return false; //<LINEFEED>
 		return true;
-	} catch (Exception e) {
-		return false;
 	}
-}
+
 /**
  * SWT does not support 16-bit depths. If this image uses
  * 16-bit depths, convert the data to an 8-bit depth.

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

@@ -14,19 +14,20 @@
 package org.eclipse.swt.internal.image;
 
 
+import java.io.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
-import java.io.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
 /**
  * Baseline TIFF decoder revision 6.0
  * Extension T4-encoding CCITT T.4 1D
  */
-public final class TIFFFileFormat extends FileFormat {
+public final class TIFFFileFormat extends StaticFileFormat {
 
-@Override
-boolean isFileFormat(LEDataInputStream stream) {
-	try {
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
 		byte[] header = new byte[4];
 		stream.read(header);
 		stream.unread(header);
@@ -36,10 +37,7 @@ boolean isFileFormat(LEDataInputStream stream) {
 			return false;
 		}
 		return true;
-	} catch (Exception e) {
-		return false;
 	}
-}
 
 @Override
 ImageData[] loadFromByteStream() {

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

@@ -14,11 +14,13 @@
 package org.eclipse.swt.internal.image;
 
 
+import java.io.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
-import java.io.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
-public final class WinBMPFileFormat extends FileFormat {
+public final class WinBMPFileFormat extends StaticFileFormat {
 	static final int BMPFileHeaderSize = 14;
 	static final int BMPHeaderFixedSize = 40;
 
@@ -415,18 +417,16 @@ int decompressRLE8Data(byte[] src, int numBytes, int stride, byte[] dest, int de
 	}
 	return 1;
 }
-@Override
-boolean isFileFormat(LEDataInputStream stream) {
-	try {
+
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
 		byte[] header = new byte[18];
 		stream.read(header);
 		stream.unread(header);
 		int infoHeaderSize = (header[14] & 0xFF) | ((header[15] & 0xFF) << 8) | ((header[16] & 0xFF) << 16) | ((header[17] & 0xFF) << 24);
 		return header[0] == 0x42 && header[1] == 0x4D && infoHeaderSize >= BMPHeaderFixedSize;
-	} catch (Exception e) {
-		return false;
 	}
-}
+
 boolean isPaletteBMP(PaletteData pal, int depth) {
 	switch(depth) {
 		case 32:

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

@@ -18,8 +18,9 @@
 
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
+import org.eclipse.swt.internal.image.FileFormat.*;
 
-public final class WinICOFileFormat extends FileFormat {
+public final class WinICOFileFormat extends StaticFileFormat {
 
 byte[] bitInvertData(byte[] data, int startIndex, int endIndex) {
 	// Destructively bit invert data in the given byte array.
@@ -54,17 +55,15 @@ int iconSize(ImageData i) {
 	int paletteSize = i.palette.colors != null ? i.palette.colors.length * 4 : 0;
 	return WinBMPFileFormat.BMPHeaderFixedSize + paletteSize + dataSize;
 }
-@Override
-boolean isFileFormat(LEDataInputStream stream) {
-	try {
+
+	@Override
+	boolean isFileFormat(LEDataInputStream stream) throws IOException {
 		byte[] header = new byte[4];
 		stream.read(header);
 		stream.unread(header);
 		return header[0] == 0 && header[1] == 0 && header[2] == 1 && header[3] == 0;
-	} catch (Exception e) {
-		return false;
 	}
-}
+
 boolean isValidIcon(ImageData i) {
 	switch (i.depth) {
 		case 1:
@@ -131,10 +130,10 @@ ImageData[] loadFromByteStream() {
  */
 ImageData loadIcon(int[] iconHeader) {
 	try {
-		FileFormat png = new PNGFileFormat();
+		StaticFileFormat png = new PNGFileFormat();
 		if (png.isFileFormat(inputStream)) {
 			png.loader = this.loader;
-			return png.loadFromStream(inputStream)[0];
+			return png.loadFromStream(inputStream, STATIC_ZOOM_FACTOR)[0];
 		}
 	} catch (Exception e) {
 	}

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/ImageLoader.java

@@ -151,7 +151,7 @@ void reset() {
 public ImageData[] load(InputStream stream) {
 	if (stream == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
 	reset();
-	data = FileFormat.load(stream, this);
+	data = FileFormat.load(stream, this, FileFormat.STATIC_ZOOM_FACTOR);
 	return data;
 }