Re: [ft-devel] Fwd: Issue 977845 in chromium: pdf_font_fuzzer: Integer-overflow in compute_glyph_metrics

2019-08-07 Thread armin
> Thanks for looking into it. FWIW, my commit merely re-enabled an older
code
> path.

NW we've already fixed a lot of those that came up in our own fuzzers :) ...
it's actually harmless but a side product of fuzzers throwing super random
input at apps.  Some overflow when facing gigantic glyphs but no one who's
truly interested in rendered results would ever use FreeType with such
inputs.  The idea is to keep the overflow as it is, but have it done in
`unsigned' world where it is actually "defined" behaviour (resulting in the
same value most likely tho).

I left a comment at
https://bugs.chromium.org/p/chromium/issues/detail?id=977845#c7 which would
help me figure out the exact line of peril much more quickly :)

Armin


___
Freetype-devel mailing list
Freetype-devel@nongnu.org
https://lists.nongnu.org/mailman/listinfo/freetype-devel


Re: [ft-devel] [GSoC'19] ftinspect update

2019-08-07 Thread Werner LEMBERG

> Quick intro: https://youtu.be/d3NuqFckEoU

Thanks!  You are making progress, which is good :-)

However, there is a lot of things that don't work right now.  Here's
my list of things that I encountered while playing with the new
features.

* The biggest problem is that glyphs in the `ftview' mode aren't
  displayed with correct vertical positions.  This is serious bug and
  must be fixed ASAP – I think I reported this already six weeks
  ago...

* I don't like that there are tabs called `Ftview' or `Ftdiff'; a new
  user has no idea what this is for.  Instead, if you select one of
  the `modes' with the radio buttons, the tabs on the left side should
  change according to the mode (having functional names that helps the
  user in navigation), and/or features that don't fit should be greyed
  out.

  Another issue is that selecting stuff from the tab suddenly changes
  the mode; for example, if I select `Grid View', then `Ftview->Render
  Mode->Stroked', the display no longer is in grid mode (but the radio
  button still shows it).  This must not happen.  As mentioned above,
  options that do not fit a mode must be disabled (or not displayed).

* If a dark desktop theme gets used, the background of the main window
  becomes dark, too.  This is quite bad, since the various gray shades
  are no longer displayed correctly.  Please ensure that always a
  white background gets used.

* `Segment Drawing' doesn't work correctly.  Segment lines appear for
  half a second, then they disappear again.  Additionally, it seems
  that if both horizontal and vertical auto-hinting is selected, even
  the short appearance can't be triggered.

  By the way, the segment lines are too thick now.  If the grid line
  has a thickness of 1px, I suggest that segment lines are 2px thick
  (i.e., ½px + 1px + ½px).

* The `All Glyphs' mode is mostly dysfunctional.  For example, the
  display doesn't get updated if I select auto-hinting.  Similarly,
  pressing the `+10' button (and friends) only adjusts a single, red
  outlined glyph that is always positioned in the center – what is
  this good for?

* Another issue with the `All Glyphs' mode: If I select a large size
  (say, 100px), I can't move the image around with my mouse.  Ditto
  for `Comparator' mode.

* If I select a large size in `All Glyphs' mode, then select `Grid
  View' the size gets respected.  However, selecting `All Glyphs' mode
  again, the size jumps back to a default size of 20px.

* All modes except `Grid View' mode lag a lot if I change parameters,
  or if I move the panel with the mouse – this indicates a problem
  with the implementation.  Please fix that.  It must work as swift as
  the `Grid View' mode.

* Please display number values on the Gamma scale (i.e., using a
  different widget for the scale).

* The Gamma scale behaves strangely: selecting values at the very
  left, the image be brighter again!  This can't be correct.

* Gamma values should work in all modes, not only `Grid View'.


Werner

___
Freetype-devel mailing list
Freetype-devel@nongnu.org
https://lists.nongnu.org/mailman/listinfo/freetype-devel