Problems with redering Tamil characters

[j605]

• Version: staging release
• Base libraries qt: 5.10.1, gcc: 8.1.0
• OS: Arch Linux Tamil text is rendered incorrectly and editing the text is an issue since. I am using the font, TAMu_Kalyani and the screenshot should show the difference in text between kate and nvim-qt.

Text taken from wikipedia

This is broken in nvim as such but I don't expect great support inside of a terminal anyway and that is why I chose to post the screenshot of kate.

[jgehrig]

I am not familiar with Tamil, but this looks like a ligature issue. I assume characters change based on their surroundings?

If the above is true, ligatures are required for rendering Tamil and this may be fixed by Pull #727 and :GuiRenderLigatures.

Related Work Items:

166 #470 #723

EDIT: :GuiRenderLigatures -> :GuiRenderLigatures 1

[j605]

When I try :GuiRenderLigatures, I get E471: Argument required.

[jgehrig]

@j605 Sorry for the confusion.

You need to provide an enable/disable argument 1 or 0, so the full command would be :GuiRenderLigatures 1.

The :GuiRenderLigatures feature is still a work in progress... There may be some font spacing or rendering issues with the current build.

[j605]

After enabling the result is much better but you can see the issues with say the dot in க் is not rendered.

[jgehrig]

Sorry, I am not familiar with Tamil. I can't distinguish the issue with that much text.

A few things may help me. Could you provide:

1. A minimal example. Can you trigger the issue above with 1-10 words only?
2. Text (in addition to the screenshot) for me to copy-paste?
3. The specific font you are using?

I'm glad to hear the issue is better. We are moving in the right direction...

[j605]

The text is taken from wikipedia. You can see it in the first few words itself. The first sentence for example,

கொழுப்பு அமிலம் (Fatty acid) என்பது நிறைவுற்ற அல்லது நிறைவுறாத, நீளமான, கிளைக்காத, கொழுப்பார்ந்த பின் தொடரியைக் கொண்ட கார்பாக்சிலிக் அமிலமாகும்.

The dots on top of the letters are not rendered in my screenshot in neovim-qt but are fine in kate.