>>>> When drawing to Java Graphics2D It seems like iText does not support >>>> GradientPaint gradients with transparency? >>> You're right, I don't think that's supported. >> >> I had a look at the relevant iText code and lucky for me I managed to >> get it going by only changing one line :) >> I'm using only RGB at this point so I changed >> com.lowagie.text.pdf.PdfShading line 145 to also return the alpha value. >> The full function is below and the new and improved PDF output from my >> previous example is here: >> http://al.chemy.org/misc/graphics2D-2.pdf >> Beautiful isn't it! > > As far as I can see, the change breaks other examples... Yes you are right. It worked straight away in Apple's default PDF reader Preview, but unfortunately I didn't test it fully on Windows etc... Different PDF readers seem to react differently. The worst case scenario is that the files will not even open, otherwise only the transparency may be lost and the colour maintained.
I am still interested in implementing this, and have mocked up a transparent gradient in Adobe Illustrator and checked the pdf output. In general the output is very bloated compared to iText, but it looks like a shape is drawn with a transparent mask on top of it (as opposed to using the straight ARGB colours I plugged in last time). The relevant tags in the pdf go something like this: <</I false/K false/CS/DeviceRGB/S/Transparency>> .. <</OPM 1/BM/Normal/CA 1.0/OP false/SMask 18 0 R/ca 1.0/AIS false/op false/Type/ExtGState/SA true>> .. <</G 17 0 R/S/Luminosity/Type/Mask/BC 19 0 R>> .. <</Subtype/Form/Length 67/Matrix[1.0 0.0 0.0 1.0 0.0 0.0]/Group 8 0 R/ Resources<</XObject<</Fm0 16 0 R>>/ExtGState<</GS0 21 0 R>>>>/ BBox[455.781 456.219 579.219 332.781]>>stream The file itself is here (a 123x123 box at x456 y456): http://al.chemy.org/misc/GradientTransparencyAiTest.pdf So my question is... what do you think is the best way to implement this functionality using Graphics2D? Either with a workaround in the application or by extending iText itself. Thank you again for your time! I really appreciate it. Best, Karl - Alchemy An open drawing project http://al.chemy.org - ------------------------------------------------------------------------------ This SF.net email is sponsored by: High Quality Requirements in a Collaborative Environment. Download a free trial of Rational Requirements Composer Now! http://p.sf.net/sfu/www-ibm-com _______________________________________________ iText-questions mailing list iText-questions@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/itext-questions Buy the iText book: http://www.1t3xt.com/docs/book.php
