December 16, 2006 Leave a comment
Let me insert a small break in my series of font lectures to show the latest and greatest screenshots. Just today I got the first hinted text rendered (left without hinting, right with hinting):
Both are rendered using Sun’s Graphics2D impl with anti-aliasing turned on (via Graphics2D.fill(Shape) ). The outcome is quite similar with Cairo though. Unfortunately I haven’t found a rasterizer yet that can render this thing properly without AA. Classpath’s Cairo backend doesn’t support turning off AA right now and Sun’s rasterizer fails to render this nicely without AA, although I’m sure that the outlines are ok now. But Graphis2D.fill(Shape) is not exactly a font renderer though. I haven’t tried the X peers with the Java-only rasterizer yet. I will try this soon though.
Francis was so kind to quickly implement support for non-AA rendering. Here comes the comparison for rendering hinted text without AA. Left Sun, right Cairo (yes!):
This seems to confirm that the general hinting is mostly ok. The missing curve segments in the e and o are quite certainly to blame to Sun’s rasterizer. However, there are definitely small glitches in the hinting still, visible in the W, r and d glyphs.
Here are some more unsorted screenshots on my way to a hinting implementation:
A little accident:
Some glyph outlines with the original (red) and hinted (green) shapes magnified to show the grid-fit:
Again, the ‘e’ glyph, where hinting was a work in progress. I made this screenshot for debugging purposes. Notice how the middle horizontal stem got accidentally collapsed:
While working with this I stumbled over a bug in Classpath’s Cairo peers when trying to render a shape magnified. Is this abstract art? (This should have been the ‘e’ glyph above).