Two transcoding hints (KEY_WIDTH and * KEY_HEIGHT) can be used to respectively specify the image * width and the image height. If only one of these keys is specified, * the transcoder preserves the aspect ratio of the original image. * *
The KEY_BACKGROUND_COLOR defines the background color * to use for opaque image formats, or the background color that may * be used for image formats that support alpha channel. * *
The KEY_AOI represents the area of interest to paint * in device space. * *
Three additional transcoding hints that act on the SVG * processor can be specified: * *
KEY_LANGUAGE to set the default language to use (may be * used by a <switch> SVG element for example), * KEY_USER_STYLESHEET_URI to fix the URI of a user * stylesheet, and KEY_PIXEL_TO_MM to specify the pixel to * millimeter conversion factor. * * @author Keiron Liddle * @version $Id$ */ public class PDFTranscoder extends XMLAbstractTranscoder { public static final TranscodingHints.Key KEY_STROKE_TEXT = new StringKey(); /** * The user agent dedicated to an ImageTranscoder. */ protected UserAgent userAgent = new ImageTranscoderUserAgent(); /** * Constructs a new ImageTranscoder. */ public PDFTranscoder() { hints.put(KEY_DOCUMENT_ELEMENT_NAMESPACE_URI, SVGConstants.SVG_NAMESPACE_URI); hints.put(KEY_DOCUMENT_ELEMENT, SVGConstants.SVG_SVG_TAG); hints.put(KEY_DOM_IMPLEMENTATION, SVGDOMImplementation.getDOMImplementation()); } /** * Transcodes the specified Document as an image in the specified output. * * @param document the document to transcode * @param uri the uri of the document or null if any * @param output the ouput where to transcode * @exception TranscoderException if an error occured while transcoding */ protected void transcode(Document document, String uri, TranscoderOutput output) throws TranscoderException { if (!(document instanceof SVGOMDocument)) { throw new TranscoderException(Messages.formatMessage("notsvg", null)); } SVGDocument svgDoc = (SVGDocument)document; SVGSVGElement root = svgDoc.getRootElement(); // initialize the SVG document with the appropriate context String parserClassname = (String)hints.get(KEY_XML_PARSER_CLASSNAME); DefaultSVGContext svgCtx = new DefaultSVGContext(); svgCtx.setPixelToMM(userAgent.getPixelToMM()); ((SVGOMDocument)document).setSVGContext(svgCtx); /*boolean stroke = true; if (hints.containsKey(KEY_STROKE_TEXT)) { stroke = ((Boolean)hints.get(KEY_STROKE_TEXT)).booleanValue(); }*/ PDFDocumentGraphics2D graphics = new PDFDocumentGraphics2D(false); // build the GVT tree GVTBuilder builder = new GVTBuilder(); BridgeContext ctx = new BridgeContext(userAgent); TextPainter textPainter = null; textPainter = new StrokingTextPainter(); ctx.setTextPainter(textPainter); PDFTextElementBridge pdfTextElementBridge = new PDFTextElementBridge(graphics.getFontState()); ctx.putBridge(pdfTextElementBridge); PDFAElementBridge pdfAElementBridge = new PDFAElementBridge(); AffineTransform currentTransform = new AffineTransform(1, 0, 0, 1, 0, 0); pdfAElementBridge.setCurrentTransform(currentTransform); ctx.putBridge(pdfAElementBridge); ctx.putBridge(new PDFImageElementBridge()); GraphicsNode gvtRoot; try { gvtRoot = builder.build(ctx, svgDoc); } catch (BridgeException ex) { throw new TranscoderException(ex); } // get the 'width' and 'height' attributes of the SVG document float docWidth = (float)ctx.getDocumentSize().getWidth(); float docHeight = (float)ctx.getDocumentSize().getHeight(); ctx = null; builder = null; // compute the image's width and height according the hints float imgWidth = -1; if (hints.containsKey(ImageTranscoder.KEY_WIDTH)) { imgWidth = ((Float)hints.get(ImageTranscoder.KEY_WIDTH)).floatValue(); } float imgHeight = -1; if (hints.containsKey(ImageTranscoder.KEY_HEIGHT)) { imgHeight = ((Float)hints.get(ImageTranscoder.KEY_HEIGHT)).floatValue(); } float width, height; if (imgWidth > 0 && imgHeight > 0) { width = imgWidth; height = imgHeight; } else if (imgHeight > 0) { width = (docWidth * imgHeight) / docHeight; height = imgHeight; } else if (imgWidth > 0) { width = imgWidth; height = (docHeight * imgWidth) / docWidth; } else { width = docWidth; height = docHeight; } // compute the preserveAspectRatio matrix AffineTransform Px; String ref = null; try { ref = new URL(uri).getRef(); } catch (MalformedURLException ex) { // nothing to do, catched previously } try { Px = ViewBox.getViewTransform(ref, root, width, height); } catch (BridgeException ex) { throw new TranscoderException(ex); } if (Px.isIdentity() && (width != docWidth || height != docHeight)) { // The document has no viewBox, we need to resize it by hand. // we want to keep the document size ratio float d = Math.max(docWidth, docHeight); float dd = Math.max(width, height); float scale = dd / d; Px = AffineTransform.getScaleInstance(scale, scale); } // take the AOI into account if any if (hints.containsKey(ImageTranscoder.KEY_AOI)) { Rectangle2D aoi = (Rectangle2D)hints.get(ImageTranscoder.KEY_AOI); // transform the AOI into the image's coordinate system aoi = Px.createTransformedShape(aoi).getBounds2D(); AffineTransform Mx = new AffineTransform(); double sx = width / aoi.getWidth(); double sy = height / aoi.getHeight(); Mx.scale(sx, sy); double tx = -aoi.getX(); double ty = -aoi.getY(); Mx.translate(tx, ty); // take the AOI transformation matrix into account // we apply first the preserveAspectRatio matrix Px.preConcatenate(Mx); } // prepare the image to be painted int w = (int)width; int h = (int)height; graphics.setupDocument(output.getOutputStream(), w, h); graphics.setSVGDimension(docWidth, docHeight); currentTransform.setTransform(1, 0, 0, -1, 0, height); /*if (!stroke) { textPainter = new PDFTextPainter(graphics.getFontState()); ctx.setTextPainter(textPainter); }*/ if (hints.containsKey(ImageTranscoder.KEY_BACKGROUND_COLOR)) { graphics.setBackgroundColor((Color)hints.get(ImageTranscoder.KEY_BACKGROUND_COLOR)); } graphics.setGraphicContext(new org.apache.batik.ext.awt.g2d.GraphicContext()); gvtRoot.paint(graphics); try { graphics.finish(); } catch (Exception ex) { ex.printStackTrace(); throw new TranscoderException(ex); } } /** * Creates a DocumentFactory that is used to create an SVG DOM * tree. The specified DOM Implementation is ignored and the Batik * SVG DOM Implementation is automatically used. * * @param domImpl the DOM Implementation (not used) * @param parserClassname the XML parser classname */ protected DocumentFactory createDocumentFactory(DOMImplementation domImpl, String parserClassname) { return new SAXSVGDocumentFactory(parserClassname); } // -------------------------------------------------------------------- // UserAgent implementation // -------------------------------------------------------------------- /** * A user agent implementation for ImageTranscoder. */ protected class ImageTranscoderUserAgent extends UserAgentAdapter { /** * Returns the default size of this user agent (400x400). */ public Dimension2D getViewportSize() { return new Dimension(400, 400); } /** * Displays the specified error message using the ErrorHandler. */ public void displayError(String message) { try { getErrorHandler().error(new TranscoderException(message)); } catch (TranscoderException ex) { throw new RuntimeException(); } } /** * Displays the specified error using the ErrorHandler. */ public void displayError(Exception e) { try { getErrorHandler().error(new TranscoderException(e)); } catch (TranscoderException ex) { throw new RuntimeException(); } } /** * Displays the specified message using the ErrorHandler. */ public void displayMessage(String message) { try { getErrorHandler().warning(new TranscoderException(message)); } catch (TranscoderException ex) { throw new RuntimeException(); } } /** * Returns the pixel to millimeter conversion factor specified in the * TranscodingHints or 0.3528 if any. */ public float getPixelToMM() { if (getTranscodingHints().containsKey(ImageTranscoder.KEY_PIXEL_TO_MM)) { return ((Float)getTranscodingHints().get(ImageTranscoder.KEY_PIXEL_TO_MM)).floatValue(); } else { // return 0.3528f; // 72 dpi return 0.26458333333333333333333333333333f; // 96dpi } } /** * Returns the user language specified in the * TranscodingHints or "en" (english) if any. */ public String getLanguages() { if (getTranscodingHints().containsKey(ImageTranscoder.KEY_LANGUAGE)) { return (String)getTranscodingHints().get(ImageTranscoder.KEY_LANGUAGE); } else { return "en"; } } public String getMedia() { return "print"; } /** * Returns the user stylesheet specified in the * TranscodingHints or null if any. */ public String getUserStyleSheetURI() { return (String)getTranscodingHints().get(ImageTranscoder.KEY_USER_STYLESHEET_URI); } /** * Returns the XML parser to use from the TranscodingHints. */ public String getXMLParserClassName() { if (getTranscodingHints().containsKey(KEY_XML_PARSER_CLASSNAME)) { return (String)getTranscodingHints().get(KEY_XML_PARSER_CLASSNAME); } else { return XMLResourceDescriptor.getXMLParserClassName(); } } public boolean isXMLParserValidating() { return false; } /** * Unsupported operation. */ public AffineTransform getTransform() { return null; } } }