New soft mask method causes some text not to be rendered

Half of the text on this restaurant menu PDF does not render in current versions of PDF.js. I remembered that this PDF used to render correctly in Firefox, so I ran git bisect and identified commit 2d1f9ff7a3a8e29acd7500add4a1057a5eaba191 as the change which introduced the regression.

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Attach (recommended) or Link to PDF file here: Tillamook-Market-Menu-04.04.22.pdf

Configuration:

• Web browser and its version: Firefox 101.0 arm64
• Operating system and its version: macOS 12.4
• PDF.js version: git master (19539676813b5df6ca4726a1bfa6765193b1067c)
• Is a browser extension: No

Steps to reproduce the problem:

1. Open the PDF.
2. Observe that roughly half the text on the menu does not appear.

What is the expected behavior? (add screenshot)

What went wrong? (add screenshot)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension): n/a

[VictoriaSarycheva]

Hello! We have a 2 big customers with the same problem, please, post here any updates (@Snuffleupagus would be so much appreciated)

[Snuffleupagus]

Having managed to create a slightly smaller test-case, see issue14982_reduced.pdf, I now understand more specifically what breaks. Although I’ve not managed to (immediately) see how to fix this, however the problem is connected to SMasks larger than https://github.com/mozilla/pdf.js/blob/987062c302c01bab72645e28a1ffa3fd457e1eb6/src/display/canvas.js#L49 since disabling the following code “fixes” this, and the duplicate, issue https://github.com/mozilla/pdf.js/blob/987062c302c01bab72645e28a1ffa3fd457e1eb6/src/display/canvas.js#L2665-L2672 Looking at the old code, we were previously taking the smask.scaleX/smask.scaleY into account during composeSMask. Unfortunately trying to restore, a variant of, that code doesn’t work and most likely other (possibly larger) changes are required.