QSvgRenderer segmentation fault

Question

I realize specific questions like this aren't great, but I've spent several days trying to puzzle this out. Hopefully someone here can help.

This python code using PyQt4 causes a segmentation fault:

data = """<?xml version="1.0" ?>
          <svg height="1000" width="2000">
              <text>blah</text>
          </svg>"""

svg = QSvgRenderer(QByteArray(data))
qim = QImage(int(width), int(height), QImage.Format_ARGB32)
painter = QPainter()

painter.begin(qim)
svg.render(painter)
painter.end()

qim.save('test2.png')

The line that causes the fault is svg.render(painter).

The fault points at libQtGui.so (so something in QPainter or QImage).

svg.isValid() returns True, and qim.isNull() returns False.

Answer 1

Try making it draw on a QPixmap instead of a QImage.

Qt does cause segfaults once in a while, I usually just code around them. Maybe you could rasterize this SVG in Gimp and just load that.

Answer 2

With only a minor change to make that run (defining width and height), it works for me. Note that I don't see any text but if I swap out data to something I know is valid it works perfectly. Here's my full code:

#!/usr/bin/env python

from  PyQt4.QtGui import *
from  PyQt4.QtCore import *
from PyQt4.QtSvg import *
import sys

if __name__ == '__main__':

    app = QApplication(sys.argv)

    data = """... (my valid svg) ..."""

    svg = QSvgRenderer(QByteArray(data))
    qim = QImage(int(2000), int(1000), QImage.Format_ARGB32)                                                                                                                                                                                 
    painter = QPainter()

    painter.begin(qim)
    svg.render(painter)
    painter.end()

    print "null:", qim.isNull()
    qim.save('test2.png')