GC.drawImage()
+ * and display on widgets with, for example, Button.setImage().
+ *
+ * If loaded from a file format that supports it, an
+ * Image may have transparency, meaning that certain
+ * pixels are specified as being transparent when drawn. Examples
+ * of file formats that support transparency are GIF and PNG.
+ *
+ * There are two primary ways to use Images.
+ * The first is to load a graphic file from disk and create an
+ * Image from it. This is done using an Image
+ * constructor, for example:
+ *
+ * Image i = new Image(device, "C:\\graphic.bmp"); + *+ * A graphic file may contain a color table specifying which + * colors the image was intended to possess. In the above example, + * these colors will be mapped to the closest available color in + * SWT. It is possible to get more control over the mapping of + * colors as the image is being created, using code of the form: + *
+ * ImageData data = new ImageData("C:\\graphic.bmp");
+ * RGB[] rgbs = data.getRGBs();
+ * // At this point, rgbs contains specifications of all
+ * // the colors contained within this image. You may
+ * // allocate as many of these colors as you wish by
+ * // using the Color constructor Color(RGB), then
+ * // create the image:
+ * Image i = new Image(device, data);
+ *
+ *
+ * Applications which require even greater control over the image
+ * loading process should use the support provided in class
+ * ImageLoader.
+ *
+ * Application code must explicitly invoke the Image.dispose()
+ * method to release the operating system resources managed by each instance
+ * when those instances are no longer required.
+ *
+ * IMPORTANT: This method is not part of the public
+ * API for Image. It is marked public only so that it
+ * can be shared within the packages provided by SWT. It is not
+ * available on all platforms, and should never be called from
+ * application code.
+ *
SWT.BITMAP, SWT.ICON)
+ * + * IMPORTANT: This field is not part of the SWT + * public API. It is marked public only so that it can be shared + * within the packages provided by SWT. It is not available on all + * platforms and should never be accessed from application code. + *
+ */ + public int type = SWT.BITMAP; + + /* + * The alpha data of the image. + */ + byte[] alphaData; + + /* + * The global alpha value to be used for every pixel. + */ + int alpha = SWT.DEFAULT; + + /* + * Specifies the default scanline padding. + */ + static final int DEFAULT_SCANLINE_PAD = 4; + + private org.eclipse.swt.internal.qt.graphics.Image cgImage; + + /* + * Handle to the QIcon for this Image + */ + private int icon = SWT.NULL; + + /* + * specifies the transparent pixel + * (Warning: This field is platform dependent) + */ + int transparentPixel = -1; + + /* + * Device + */ + Device device; + + /** + * Prevents uninitialized instances from being created outside the package. + * @param device Device + */ + Image(Device device) { + if (device == null) device = Device.getDevice(); + if (device == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); + this.device = device; + } + + /** + * Constructs an instance of this class from the given + *ImageData.
+ *
+ * @param device the device on which to create the image
+ * @param data the image data to create the image from (must not be null)
+ *
+ * @exception IllegalArgumentException
+ * This constructor is provided for convenience when loading a single
+ * image only. If the stream contains multiple images, only the first
+ * one will be loaded. To load multiple images, use
+ * ImageLoader.load().
+ *
+ * This constructor may be used to load a resource as follows: + *
+ *
+ * static Image loadImage (Display display, Class clazz, String string) {
+ * InputStream stream = clazz.getResourceAsStream (string);
+ * if (stream == null) return null;
+ * Image image = null;
+ * try {
+ * image = new Image (display, stream);
+ * } catch (SWTException ex) {
+ * } finally {
+ * try {
+ * stream.close ();
+ * } catch (IOException ex) {}
+ * }
+ * return image;
+ * }
+ *
+ *
+ * @param device the device on which to create the image
+ * @param stream the input stream to load the image from
+ *
+ * @exception IllegalArgumentException + * Image i = new Image(device, width, height); + * GC gc = new GC(i); + * gc.drawRectangle(0, 0, 50, 50); + * gc.dispose(); + *+ *
+ * Note: Some platforms may have a limitation on the size + * of image that can be created (size depends on width, height, + * and depth). For example, Windows 95, 98, and ME do not allow + * images larger than 16M. + *
+ * + * @param device the device on which to create the image + * @param width the width of the new image + * @param height the height of the new image + * + * @exception IllegalArgumentException+ * Image i = new Image(device, boundsRectangle); + * GC gc = new GC(i); + * gc.drawRectangle(0, 0, 50, 50); + * gc.dispose(); + *+ *
+ * Note: Some platforms may have a limitation on the size + * of image that can be created (size depends on width, height, + * and depth). For example, Windows 95, 98, and ME do not allow + * images larger than 16M. + *
+ * + * @param device the device on which to create the image + * @param bounds a rectangle specifying the image's width and height (must not be null) + * + * @exception IllegalArgumentException+ * This constructor is provided for convenience when loading + * a single image only. If the specified file contains + * multiple images, only the first one will be used. + * + * @param device the device on which to create the image + * @param filename the name of the file to load the image from + * + * @exception IllegalArgumentException
true if the object is the same as
+ * this object and false otherwise
+ *
+ * @see #hashCode
+ */
+ public boolean equals (Object object) {
+ if (object == this) {
+ return true;
+ }
+ if (!(object instanceof Image)) {
+ return false;
+ }
+ Image image = (Image)object;
+ return (
+ (device == image.device) &&
+ (hashCode() == image.hashCode()));
+ }
+
+ /**
+ * Returns the bounds of the receiver. The rectangle will always
+ * have x and y values of 0, and the width and height of the
+ * image.
+ *
+ * @return a rectangle specifying the image's bounds
+ *
+ * @exception SWTException ImageData based on the receiver
+ * Modifications made to this ImageData will not
+ * affect the Image.
+ *
+ * @return an ImageData containing the image's data and attributes
+ *
+ * @exception SWTException true when passed to
+ * equals must return the same value for this
+ * method.
+ *
+ * @return the receiver's hash
+ *
+ * @see #equals
+ */
+ public int hashCode () {
+ if(cgImage != null) {
+ return cgImage.getHandle();
+ }
+ return SWT.DEFAULT;
+ }
+
+ /*
+ * Helper method for constructing an empty instance of this class with the
+ * specified width and height.
+ */
+ void init() {
+ if(cgImage != null && !cgImage.isDisposed()) {
+ cgImage.dispose();
+ }
+ }
+
+ /*
+ * Helper method for constructing an empty instance of this class with the
+ * specified image data.
+ *
+ * @param imageData The image data
+ */
+ void init(ImageData image) {
+ if (image == null) {
+ SWT.error(SWT.ERROR_NULL_ARGUMENT);
+ }
+
+ if (!(((image.depth == 1 || image.depth == 2 ||
+ image.depth == 4 || image.depth == 8) && !image.palette.isDirect) ||
+ ((image.depth == 8) || (image.depth == 16 ||
+ image.depth == 24 || image.depth == 32) && image.palette.isDirect))) {
+ SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
+ }
+
+ init();
+
+ int width = image.width;
+ int height = image.height;
+ PaletteData palette = image.palette;
+ if (!(((image.depth == 1 || image.depth == 2 || image.depth == 4 || image.depth == 8) && !palette.isDirect) ||
+ ((image.depth == 8) || (image.depth == 16 || image.depth == 24 || image.depth == 32) && palette.isDirect)))
+ SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
+ byte[] buffer = image.data;
+ if (image.depth != 32 || image.bytesPerLine != width*4) {
+ buffer = new byte[width * 4 * height];
+ if (palette.isDirect) {
+ ImageData.blit(ImageData.BLIT_SRC,
+ image.data, image.depth, image.bytesPerLine, image.getByteOrder(), 0, 0, width, height, palette.redMask, palette.greenMask, palette.blueMask,
+ ImageData.ALPHA_OPAQUE, null, 0, 0, 0,
+ buffer, 32, width*4, ImageData.MSB_FIRST, 0, 0, width, height, 0x00FF0000, 0x0000FF00, 0x000000FF,
+ false, false);
+ palette = new PaletteData(0x00FF0000, 0x0000FF00, 0x000000FF);
+ } else {
+ RGB[] rgbs = palette.getRGBs();
+ int length = rgbs.length;
+ byte[] srcReds = new byte[length];
+ byte[] srcGreens = new byte[length];
+ byte[] srcBlues = new byte[length];
+ for (int i = 0; i < rgbs.length; i++) {
+ RGB rgb = rgbs[i];
+ if (rgb == null) continue;
+ srcReds[i] = (byte)rgb.red;
+ srcGreens[i] = (byte)rgb.green;
+ srcBlues[i] = (byte)rgb.blue;
+ }
+ ImageData.blit(ImageData.BLIT_SRC,
+ image.data, image.depth, image.bytesPerLine, image.getByteOrder(), 0, 0, width, height, srcReds, srcGreens, srcBlues,
+ ImageData.ALPHA_OPAQUE, null, 0, 0, 0,
+ buffer, 32, width*4, ImageData.MSB_FIRST, 0, 0, width, height, 0x00FF0000, 0x0000FF00, 0x000000FF,
+ false, false);
+ }
+
+ image = new ImageData(width, height, 32, palette, 4, buffer, image.maskPad, image.maskData,
+ image.alphaData, image.alpha, image.transparentPixel, image.type,
+ image.x, image.y, image.disposalMethod, image.delayTime);
+ }
+
+ this.type = SWT.BITMAP;
+ cgImage =
+ new org.eclipse.swt.internal.qt.graphics.Image(image);
+
+ try {
+ if (image.transparentPixel != -1) {
+ RGB rgb = null;
+ if (palette.isDirect) {
+ rgb = palette.getRGB(image.transparentPixel);
+ } else {
+ if (image.transparentPixel < palette.colors.length) {
+ rgb = palette.getRGB(image.transparentPixel);
+ }
+ }
+
+ if (rgb != null) {
+ transparentPixel = rgb.red << 24 | rgb.green << 16 | rgb.blue << 8 | 0xFF;
+ }
+ }
+ } catch(Error e) {
+ cgImage.dispose();
+ throw e;
+ }
+ }
+
+ /*
+ * Helper method for constructing an empty instance of this class with the
+ * specified width and height.
+ *
+ * @param width the width of the new image
+ * @param height the height of the new image
+ *
+ * @see #Image(Device device, int width, int height)
+ * @see #Image(Device device, Rectangle bounds)
+ */
+ void init(int width, int height) {
+ if (width <= 0 || height <= 0) {
+ SWT.error (SWT.ERROR_INVALID_ARGUMENT);
+ }
+ init();
+ this.type = SWT.BITMAP;
+ cgImage =
+ new org.eclipse.swt.internal.qt.graphics.Image(
+ width, height);
+ }
+
+ /*
+ * Helper method for constructing an instance of this class with the
+ * specified internal image.
+ *
+ * @param iinternalImage The internal image.
+ */
+ void init(org.eclipse.swt.internal.qt.graphics.Image cgImage) {
+ if (cgImage == null) {
+ SWT.error(SWT.ERROR_NULL_ARGUMENT);
+ }
+ if (cgImage.isDisposed()) {
+ SWT.error (SWT.ERROR_UNSUPPORTED_DEPTH);
+ }
+ init();
+ this.type = SWT.BITMAP;
+ this.cgImage = cgImage;
+ }
+
+ /**
+ * Invokes platform specific functionality to dispose a GC handle.
+ *
+ * IMPORTANT: This method is not part of the public
+ * API for Image. It is marked public only so that it
+ * can be shared within the packages provided by SWT. It is not
+ * available on all platforms, and should never be called from
+ * application code.
+ *
+ * IMPORTANT: This method is not part of the public
+ * API for Image. It is marked public only so that it
+ * can be shared within the packages provided by SWT. It is not
+ * available on all platforms, and should never be called from
+ * application code.
+ *
true if the image has been disposed,
+ * and false otherwise.
+ *
+ * This method gets the dispose state for the image.
+ * When an image has been disposed, it is an error to
+ * invoke any other method using the image.
+ *
+ * @return true when the image is disposed and false otherwise
+ */
+ public boolean isDisposed() {
+ if(this.cgImage != null) {
+ return cgImage.isDisposed();
+ }
+ return true;
+ }
+
+ void setLoadSize(org.eclipse.swt.internal.qt.graphics.ImageLoader loader) {
+ Point loadSize = Internal_PackageSupport.readAndClearImageLoadSize((Display)device);
+ if(loadSize != null) {
+ loader.setLoadSize(loadSize.x, loadSize.y);
+ }
+ }
+
+ /**
+ * Returns a string containing a concise, human-readable
+ * description of the receiver.
+ *
+ * @return a string representation of the receiver
+ */
+ public String toString () {
+ if (isDisposed()) return "Image {*DISPOSED*}";
+ return "Image {" + cgImage.getHandle() + "}";
+ }
+
+ /*
+ * Call this only after dealing with all exceptions!
+ */
+ private void track() {
+ if (device.tracking) device.new_Object(this);
+ }
+}