[PDFBOX-4958] AcroForm flatten - correct calculation of appearence position

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.21, 3.0.0 PDFBox
• Fix Version/s: 2.0.22, 3.0.0 PDFBox
• Component/s: AcroForm, Rendering
• Labels: Appearance
• Assignee: Maruan Sahyoun
• Reporter: Maruan Sahyoun
• Created: 13/Sep/20 09:57
• Updated: 6 days ago 17:17
• Resolved: 30/Sep/20 10:33

Description

As discussed in https://stackoverflow.com/a/54091766/1729265 and PDFBOX-4955 the calculation of the appearance position is wrong and works only under certain conditions which are not in line with the spec.

Issue Links

• relates to: PDFBOX-4270 Image in field disappears after flattening
• relates to: PDFBOX-4430 Missing transformation in flatterning when an XObject is used as appearance of a form field