[BATIK-1109] svggen.font.SVGFont doesn't always calculate the correct path

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.7
• Component/s: SVGGraphics2D
• Assignee: Unassigned
• Reporter: Tilman Hausherr
• Created: 15/Feb/15 13:12
• Updated: 16/Feb/15 11:54

Description

We at PDFBox have used the code at
https://svn.apache.org/viewvc/xmlgraphics/batik/trunk/sources/org/apache/batik/svggen/font/SVGFont.java?view=markup
for TT font rendering. There've been some problems (see PDFBOX-1435, scroll to second half), and after bugfixes didn't work (see PDFBOX-1206), I had the idea to create a SVG file by hand with the calculations mentioned in the file.

I calculated the SVG values for the outer circle of that "o" of PDFBOX-1435 with the Batik source and added 100 to each y value (before I found out that svg allows translating). Here's the svg file I get:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="12cm" viewBox="0 0 1200 1200"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <rect x="1" y="1" width="1000" height="1000"
        fill="none" stroke="blue" stroke-width="1" />
<g transform="scale(7)">
  <path d="M85,53 T74,49 T54,48.5 T39.5,59.5 T35.5,76.5 T44,94 T62,102 T79.5,97 T89.5,82.5 T88.5,63 Z"
        fill="none" stroke="red" stroke-width="5"  />
</g>
</svg>

This can be displayed with firefox, and this "o" has an angle The reason is that the Batik algorithm doesn't work for contours made entirely with off-curve points.

I didn't actually run the Batik code, the calculations were done on paper.

Further thoughts on the TT path drawing algorithm can be found at PDFBOX-1206. We ended up using the code from PDF.js, and maybe you should too

Issue Links

• relates to: PDFBOX-1206 TrueType glyphs render incorrectly
• relates to: PDFBOX-1435 text is obscured by the Images