Hi, It works great. Thanks for working on this so quickly!
Olivier On Mon, 20 Jul 2026 at 16:30, Tilman Hausherr <[email protected]> wrote: > Hi, > > Thanks for the comfirmation and the suggestion. I've committed it and > there's a snapshot build in > > https://repository.apache.org/content/groups/snapshots/org/apache/pdfbox/pdfbox-app/3.0.9-SNAPSHOT/ > > or get it from the repository and build yourself. > > Tilman > > On 2026/07/20 12:45:53 Olivier Bruchez wrote: > > Hi Tilman, > > > > It's way cleaner than my POC. > > > > I tested your changes locally (the setFont change plus the splitter > map). I > > got the same speedup as my original patch, with no output change. On a > > 96-page PDF, the time spent drawing text went from 3.1 s to 0.85 s. > > > > That's great. Thanks a lot! > > > > Olivier > > > > On Fri, 17 Jul 2026 at 15:08, Tilman Hausherr <[email protected]> wrote: > > > > > Hi, > > > > > > I prefer something more simple because I don't want to keep a static > map > > > forever. Like this: > > > > > > Map<String,GlyphArraySplitter> map = new WeakHashMap<>(); > > > > > > and in applyGsubFeature: > > > > > > GlyphArraySplitter glyphArraySplitter = > > > map.computeIfAbsent(scriptFeature.getName(), (__) -> new > > > GlyphArraySplitterRegexImpl(allGlyphIdsForSubstitution)); > > > > > > is this what you had in mind? > > > > > > Tilman > > > > > > On 2026/07/17 10:08:44 Olivier Bruchez wrote: > > > > Hi Tilman, > > > > > > > > Thanks for your reply and for opening an issue. > > > > > > > > > > > > > I assume what you did was to check the gsubWorkers map before > calling > > > > > gsubWorkerFactory.getGsubWorker(), correct? > > > > > > > > > > > > > Not exactly. I should have included my patch/"hack" in the original > > > message > > > > for more clarity. I'm basically simply adding a global cache for the > > > > GlyphArraySplitter, inside GsubWorkerForLatin. I left setFont and the > > > > gsubWorkers map alone. It is built in applyGsubFeature (once per > > > showText), > > > > not in the constructor, so reusing the GsubWorker alone would not > stop > > > the > > > > rebuild and the performance hit. I memoized the GlyphArraySplitter > per > > > font > > > > and then per script feature (I think this is correct, but I'm not > 100% > > > > sure). > > > > > > > > The whole change is one line in applyGsubFeature: > > > > > > > > - GlyphArraySplitter glyphArraySplitter = new > > > > > > > > GlyphArraySplitterRegexImpl(scriptFeature.getAllGlyphIdsForSubstitution()); > > > > + GlyphArraySplitter glyphArraySplitter = splitterFor(scriptFeature); > > > > > > > > > > > > https://github.com/apache/pdfbox/blob/3.0.4/fontbox/src/main/java/org/apache/fontbox/ttf/gsub/GsubWorkerForLatin.java#L91-L92 > > > > > > > > Plus a static cache keyed on the font's GsubData and a small helper: > > > > > > > > private static final Map<GsubData, Map<String, GlyphArraySplitter>> > > > > SPLITTER_CACHE = new WeakHashMap<>(); > > > > > > > > private GlyphArraySplitter splitterFor(ScriptFeature scriptFeature) > > > > { > > > > synchronized (SPLITTER_CACHE) > > > > { > > > > Map<String, GlyphArraySplitter> perFont = > > > > SPLITTER_CACHE.get(gsubData); > > > > if (perFont == null) > > > > { > > > > perFont = new HashMap<>(); > > > > SPLITTER_CACHE.put(gsubData, perFont); > > > > } > > > > GlyphArraySplitter splitter = > > > perFont.get(scriptFeature.getName()); > > > > if (splitter == null) > > > > { > > > > splitter = new > > > > > > > > GlyphArraySplitterRegexImpl(scriptFeature.getAllGlyphIdsForSubstitution()); > > > > perFont.put(scriptFeature.getName(), splitter); > > > > } > > > > return splitter; > > > > } > > > > } > > > > > > > > This is a proof of concept, of course. This was just to convince > myself > > > > that rebuilding GlyphArraySplitter multiple times was indeed the > problem > > > I > > > > was observing. On larger PDF files (dozens of pages), the speedup > with > > > the > > > > code above is really huge (3-4x on the total PDF generation times). > > > > > > > > Thanks, > > > > Olivier > > > > > > > > > > --------------------------------------------------------------------- > > > To unsubscribe, e-mail: [email protected] > > > For additional commands, e-mail: [email protected] > > > > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > >
