tree 2b4f4d75e33eb2be0eb8d873bf98dfe8b69e42ec
parent c38724c0f17bb7bc2d6dc3a336231b03711d6b7f
author Himadri Kakar <hikakar@microsoft.com> 1581585839 +0000
committer Chromium commit bot <commit-bot@chromium.org> 1581585839 +0000

Fix the rendering of scientific symbols correctly

The file in the bug contains text which has to be rendered
in "Symbol" font. This font is not embedded in the pdf file.
When rendering call comes for text that corresponds to Symbol font, the
font is fetched from the system. Even though symbol font is present on
the system, it is not picked up.

Currently, the font is fetched by following the two steps:
1. Find whether there is a matching font in the installed fonts on
   the system. This call returns font face name if found in the list of
   installed fonts.
2. Getting the font face for the required font.
   This call again iterates over all the installed fonts
   and returns the font face for the best matching font.

For the case in question:
Incorrect font whose name is a prefix of desired font is being picked up
due to GetSimilarValue() yielding the same result.

To fix this, check if the family name matches the font facename exactly,
then increase |iSimilarValue| by 4.

Bug: pdfium:1449
Change-Id: I23d5c3f5e4f26981fc6a9af2ccd0024c3f9b6102
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/64610
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Himadri Kakar <hikakar@microsoft.com>