Complex script shaping not applied in XLSX to PDF conversion (Myanmar / Devanagari)

Aspose.Cells Cloud Product Family
1

We convert XLSX to PDF with the following call, and pass no other parameters.

  PUT /v3.0/cells/convert?format=PDF
  Aspose.Cells Cloud 26.7.0

The PDFs we examined were produced on 2026-07-03 with v26.6, and we reproduced the
same result on 2026-07-30 with v26.7 (times are JST, UTC+9).

Problem
Myanmar and Devanagari text is not shaped. Characters that should combine into a
single glyph are drawn separately, and invisible marks such as U+1039 and U+094D
are drawn as visible glyphs.

Example: လက္ခဏာ
Expected: ခ stacked under က, and U+1039 not rendered at all
Actual: three separate glyphs, with U+1039 visible as a “+” shaped mark

We decoded the drawn glyphs in the output PDF through the ToUnicode CMaps and
found no ligature glyphs at all.

Myanmar: 14 glyphs map to U+1039 alone, 0 ligature glyphs
Nepali: 221 glyphs map to U+094D alone, 0 ligature glyphs

Reordering is missing as well. The Devanagari i-matra (U+093F, 94 occurrences) is
drawn after its consonant instead of before it.

The fonts are not the problem. Myanmar Text and Nirmala UI are correctly embedded
in the output PDF, and the same strings render correctly in Chrome.

We also tried

  • Converting XLSX to DOCX with Aspose.Cells, then DOCX to PDF with Aspose.Words.
    The result was the same.
  • Looking for a typography option in the API specification. We found none that
    applies to PDF output. IsFontSubstitutionCharGranularity, DefaultFont and
    DefaultEditLanguage exist only in ImageOrPrintOptions, which the PDF conversion
    does not accept, and there is no PdfSaveOptions definition.

How to reproduce
Put Myanmar or Devanagari text into a cell or a text box in an XLSX and convert it
with the call above. Any text containing a virama is enough.

Myanmar လက္ခဏာ = U+101C U+1000 U+1039 U+1001 U+100F U+102C
Devanagari शिक्षा = U+0936 U+093F U+0915 U+094D U+0937 U+093E

In the resulting PDF, U+1039 and U+094D appear as separate visible glyphs and no
ligature is formed. We can send the source file and the produced PDF on request.

Questions

  1. Does Aspose.Cells Cloud support complex script shaping for Myanmar and
    Devanagari when rendering to PDF?
  2. If it does, what are we missing?
    shaping-comparison.png (186.6 KB)
2

@VideoStep

We have received your report and are currently investigating the issue. We will update you shortly with our findings.

3

@VideoStep

After testing, the API you mentioned is working correctly. Could you please provide more details about your environment and usage scenario? We will continue to investigate and update you if we find any issues.

4

The API call works and returns a valid PDF — the problem is the text inside it, and the
environment and reproduction steps are already in my first post.

If your test produced correctly shaped output, could you share that PDF so we can compare?
In ours, U+1039 is drawn as a separate visible glyph and there is no ligature glyph anywhere
in the document.

Could you also let us know whether complex script shaping for Myanmar and Devanagari is
currently supported when rendering to PDF?

6

@VideoStep Hello, after verification, the PDF conversion interface currently does not support complex text rendering in Burmese and Sanskrit due to font shaping issues.If you have any further questions, please feel free to contact us.

7

@xuejianzhang
Thank you for confirming. That answers our main question.

To plan on our side, could you tell us a little more?

  1. Is this tracked by an existing issue? CELLSNET-53617 was opened in 2023 for the same
    kind of problem with Thai and Sinhalese in XLSX to PDF conversion, and it looks related.
  2. Is complex script shaping planned for a future release? Even a rough timeframe would
    help us decide whether to wait or to work around it.
8

@VideoStep Hello, after team discussion, there are no plans to support this feature in the short term. We suggest you evaluate other alternatives.

9

Thank you for checking with your team, and for the clear answer.

That is exactly what we needed in order to decide, and we will evaluate other
options on our side. We appreciate how quickly and directly you handled this.

10

@VideoStep

You are welcome! If you have any issues, please feel free to contact us.