tree 9779bc539d7ce358f12152cd95b5eefeeae64985
parent db1d46888d2f6496957fe7b76375918106f569cf
author Lei Zhang <thestig@chromium.org> 1648193783 +0000
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1648193783 +0000

Improve TrueType font fallback check for glyph ID 0.

Change the heuristics used to check for font fallback when drawing
TrueType fonts with glyph ID 0. In some cases, 0 means use glyph 0, and
in other cases, it means the glyph is invalid. Right now, the code tries
to use a fallback font, and if that fails, go back to the original font.
Instead of doing this back-and-forth, look at the heuristics and decide
one way or the other.

Bug: chromium:1271578
Change-Id: I71a0a6607162602d8e3fba07e80546ed3a1ce548
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/91831
Reviewed-by: Nigi <nigi@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>