Re: Re: how to extend the rendering part of fop
Hi, Eugen, try to look for a minute on the XSL-T 2.0 library graph2svg, could be found on http://graph2svg.jinak.cz/examples_en.html;. It is pure XSL-T 2.0 from XML to SVG (when using two-phase transformation even inline SVG). The source XML code of graph2svg looks very similar to Your example code. Cheers, Stepan Původní zpráva Od: gen1986 cepoi.eu...@gmail.com Předmět: Re: how to extend the rendering part of fop Datum: 03.1.2011 20:34:39 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=1.1view=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
RE: Re: how to extend the rendering part of fop
I was going to suggest SVG, the simplest way to produce a chart, but the OP asked about extensions like they already had something more complicated in mind with their mind made up about how they want to do it. http://blog.trivadis.com/blogs/andreasmengel/archive/2008/03/14/generating-svg-pie-charts-in-pdf-documents.aspx -Original Message- From: Stepan RYBAR [mailto:xryb...@seznam.cz] Sent: Monday, January 03, 2011 4:19 PM To: fop-users@xmlgraphics.apache.org Subject: Re: Re: how to extend the rendering part of fop Hi, Eugen, try to look for a minute on the XSL-T 2.0 library graph2svg, could be found on http://graph2svg.jinak.cz/examples_en.html;. It is pure XSL-T 2.0 from XML to SVG (when using two-phase transformation even inline SVG). The source XML code of graph2svg looks very similar to Your example code. Cheers, Stepan Původní zpráva Od: gen1986 cepoi.eu...@gmail.com Předmět: Re: how to extend the rendering part of fop Datum: 03.1.2011 20:34:39 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/xm lgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageConver terBarcode2G2D.java?revision=1.1view=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(myG2DConvert er); 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/xm lgraphics-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/xm lgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageConver terBarcodeXML2Barcode.java?view=markup [2] http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xm lgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageBarcod e.java?view=markup [3] http://barcode4j.cvs.sourceforge.net/viewvc/barcode4j/barcode4j/src/xm lgraphics-commons/java/org/krysalis/barcode4j/image/loader/ImageConver terBarcode2G2D.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
