[reportlab-users] Issues rendering Burmese/Myanmar in PDFs

[Robin Becker]

Not sure exactly what the google group is, but here is where we try and answer questions.

I'm not an expert, but I suspect this is the same issue we have had in the past with Thai diacritics etc etc.

The issue may be caused by the way the TTF is embedded in the PDF. To avoid very large PDF's we embed subsets; that may 
alter the way that the text is represented in the PDF content stream. additionally we may be losing something in the 
font data that's important for positioning in particular vertical metrics. I think the original contribution was for 
Latin type fonts where that information is not required.

I think PDF can represent these glyphs properly, but then the renderer application also needs to do the right thing.

To fix this we would need to find a different way to use the font in the PDF to avoid the problems we have in our ttf 
subset algorithm.


On 07/01/2021 15:52, Bobby Hagen wrote:
> Previously posted on the google group, but missing images.  Hopefully those
> come through this time. Also clarified a couple steps and wanted to follow
> up on this via the list, just in case, as we're still seeing this, even
> using the latest reportlab-3.5.59 available via pypi:
> 
> We're encountering some problems attempting to build PDFs using Burmese.
> The problem doesn't seem restricted to a specific font, as at least
> NotoSansMyanmar (https://www.google.com/get/noto/#sans-mymr) and Padauk (
> https://fonts.google.com/specimen/Padauk) both have these issues.  Although
> independent characters seem to be represented correctly, some of the vowels
> and medials (and perhaps other items as well) seem to have some rendering
> issues.
...........
-- 
Robin Becker