Hi Robert,
interesting, thanks for the insight! I'll do a bit more local testing
and commit a fix.
If I interpret the code correctly, the bounding boxes are only set when
the FontCache is filled, so the performance impact wouldn't matter too
much I suppose. I'll leave a TODO mark in the code, in case anybody
wants to continue to improve this.
Best regards,
Matthias
On 06.08.2015 11:54, Robert Meyer wrote:
Hi,
I have had dealings with this when I was implementing open-type font
support as that and Type-1 fonts share similar CharString data.
Initially I thought the bounding box was a necessary part of getting the
font to work and as such put forward two patches to FontBox. The first
fixed their CharStringRenderer which renders each character and returns
the width:
https://issues.apache.org/jira/browse/PDFBOX-1505
Once that was approved, I put forward a second patch which calculated an
accurate bounding box for the given character using the same renderer:
https://issues.apache.org/jira/browse/PDFBOX-1645
Unfortunately doing this takes a fair amount of processing power and
after reading some of their concerns, while also realising that in the
end I didn't need the bounding box, I gave up on my attempt and the
issue was closed. From my testing it was certainly possible to get very
accurate bounding boxes for Type 1 font missing metrics. Whether it
would be worth the effort implementing this is doubtful though
considering firstly the fact that we lack much of the infrastructure to
implement this, but more importantly having a detrimental impact upon
performance for these limited cases.
If Jeremias's approximation is anywhere near accurate I'd certainly
suggest giving that a go.
Robert
Date: Thu, 6 Aug 2015 09:42:12 -0300
From: matthias8...@gmx.at
To: fop-dev@xmlgraphics.apache.org
Subject: Re: SingleByteFont Patch
Hi Team,
the same issue described below, came up today on my side. I did a debug
session and what I have found out so far is, that this only happens for
Type1 fonts, that don't have a AFM file. The PFM file doesn't contain
the char metrics so the bounding boxes can't be initialized.
When transcoding SVGs to PDF, the code seems to rely on those bounding
boxes (see FOPGVTGlyphVector), so I'm wondering what a correct fix would
be. The PFMFile class contains a getFontBBox method, which, as its
JavaDoc says, returns an approximation of the bounding box. I guess
returning the approximation is better than nothing, so what I've come up
so far code-wise is:
returnFont.setLastChar(pfm.getLastChar());
for (short i = pfm.getFirstChar(); i = pfm.getLastChar(); i++) {
int cw = pfm.getCharWidth(i);
singleFont.setWidth(i, cw);
// start of my code change
int[] bbox = pfm.getFontBBox();
singleFont.setBoundingBox(i, new Rectangle(bbox[0], bbox[1], cw,
bbox[3]));
// end of my code change
}
Basically I'm using the approximation plus the current char width to
build a rectangle.
Any thoughts? Or ideas for a better fix?
Thanks Best regards,
Matthias
On 01.07.2014 08:43, Pascal Sancho wrote:
Hi,
can you file in entries in Jira, please?
see our HowTo [1] submitting patches.
[1] http://xmlgraphics.apache.org/fop/dev/#patches
2014-07-01 12:36 GMT+02:00 Kai Hofmann powers...@web.de:
Dear all,
looks like there is another bug based on the before mentioned problem:
FOPGVTGlyphVector:
private void buildBoundingBoxes() {
boundingBoxes = new Rectangle2D[glyphs.length];
for (int i = 0; i glyphs.length; i++) {
Rectangle bbox = fontMetrics.getBoundingBox(glyphs[i], fontSize);
boundingBoxes[i] = new Rectangle2D.Float(bbox.x / 100f,
-(bbox.y + bbox.height) / 100f,
bbox.width / 100f, bbox.height / 100f);
}
}
Here the result of the patched getBoundingBox seems to be used
without a null pointer check. Please keep attention on getBoundingBox
which explizitly returns null
Looks like it would help to have complete javadocs which describe
the possible return values to avoid such mistakes.
Gesendet: Dienstag, 01. Juli 2014 um 10:52 Uhr
Von: Kai Hofmann powers...@web.de
An: fop-us...@xmlgraphics.apache.org
Betreff: SingleByteFont Patch
Dear all,
I found a small bug in SingleByteFont - please see attached patch -
in getBoundingBox:
if (idx = 0 idx boundingBoxes.length)
might result in a null pointer exception, when getBoundingBox is
called before setBoudning box.
So repleace with:
if (boundingBoxes != null idx = 0 idx boundingBoxes.length)
