Hi Jeremias, Thanks for your quick response. However I'll give some more informations about what I'm trying to achieve.
A sketch of the template : ... XSL-FO tags ... <fo:instream-foreign-object... <chart:chart xmlns:c="www...charts.."> <c:pie width=".." height=".."> <c:title value="Hello Piechart"/> ... some custom tags to retrieve data ... </c:pie> </chart:chart> ... XSL-FO tags ... My elementMapping extension handles those tags and creates my objects describing the chart. 1) Actually I'm extending FONode, should I rather extend InstreamForeignObject? At some point (when the pdf is rendered) I'll use my objects to draw the chart to Graphics2D. But I will not create an Image. As you mentioned, it looks a lot like what you are doing here : [3] http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xmlgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageConverterBarcode2G2D.java?revision=1.1&view=markup So tell me if I'm wrong : I must implement Graphics2DImagePainter and AbstractImageConverter, I'll draw there my chart to the given Graphics2D. XMLGraphics will take care of integrating it into the doc (being created by fop). 2) I must also extend AbstractImage, but for the moment I don't really understand what code to write there. To register the converter programatically : FopFactory factory = FopFactory.newInstance(); factory.getImageManager().getRegistry().registerConverter(myG2DConverter); That sounds ok. 3) But I don't understand how to make the link between my objects and the registred converter. Thanks again. Eugen Jeremias Maerki-2 wrote: > > Hi Eugen > > Assuming you're using Apache FOP 1.0 or later, I would suggest to you to > write a set of plug-ins for the Apache XML Graphics Commons image loader > framework. The documentation for that is found here: > http://xmlgraphics.apache.org/commons/image-loader.html > > That's our new infrastructure for handling images. And your charting XML > is nothing other than an image in XML. A good example of such a set of > plug-ins can be found in Barcode4J: > http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xmlgraphics-commons/ > > You can see multiple ImageConverter implementations there. One converts > [1] a generic XML document into an ImageBarcode [2]. And you would > create something like an ImageChart. Furthermore, I'd go the Java2D > route (Graphics2D), so you'd add an ImageConverter which takes an > ImageChart and produces an ImageGraphics2D [3] (The code in there > basically paints your chart against a Graphics2D object). The latter can > be processed by FOP's PDF support to create high-quality vector graphics > without you having to learn about PDF specifics. The nice side-effect is > that it won't only work for PDF, but also for all other output formats > supported by FOP. > > [1] > http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xmlgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageConverterBarcodeXML2Barcode.java?view=markup > [2] > http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xmlgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageBarcode.java?view=markup > [3] > http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xmlgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageConverterBarcode2G2D.java?view=markup > > If you don't plan to put charts in external files (i.e. you use only > fo:instream-foreign-object), you can omit the Preloader, LoaderFactory > and Loader, I think. The image converters should be enough. > > If there's something that our PDFGraphics2D can't handle, we can take a > closer look at this again. > > HTH > > On 03.01.2011 16:55:32 gen1986 wrote: >> >> Hi, >> >> I'm working on a project where I have to extend FO to support custom tags >> for drawing charts. >> For doing so I've extended ElementMapping and created my custom >> ContentHandlerFactory, etc. >> Until here it's ok. I can get all the infos about the chart from the >> xsl-fo >> template. >> >> My problem is that I want now to write the chart as a stream to the PDF, >> but >> I don't know which fop classes to use for doing it the right way. Any >> help >> is welcome. >> >> If my problem isn't clear enough I can give more explanations, just let >> me >> know ;) >> >> Thanks, >> >> Eugen >> -- >> View this message in context: >> http://old.nabble.com/how-to-extend-the-rendering-part-of-fop-tp30579066p30579066.html >> Sent from the FOP - Users mailing list archive at Nabble.com. > > > Jeremias Maerki > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: fop-users-unsubscr...@xmlgraphics.apache.org > For additional commands, e-mail: fop-users-h...@xmlgraphics.apache.org > > > -- View this message in context: http://old.nabble.com/how-to-extend-the-rendering-part-of-fop-tp30579066p30580808.html Sent from the FOP - Users mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: fop-users-unsubscr...@xmlgraphics.apache.org For additional commands, e-mail: fop-users-h...@xmlgraphics.apache.org
