DynamicFont render issues when instanced.

[vicguedez]

Godot version:
Godot 3.2.2 stable, official.

OS/device including version:
Windows 10 (up to date), AMD Ryzen 3500U with Vega 8 graphics.

Issue description:
I'm building a small administrative "ecosystem", so I made a small "sdk" to share among a couple of projects. I have a base "button.tscn" which I use everywhere (I also have "label.tscn" and so on...). This base scenes all load "font_base.tres" as the custom font. I'm using the Ubuntu Light font.

Now, upon switching between scenes I get this:

If I render something on top of it:

It gets fixed:

As a test, I made a new custom font for a few instanced buttons (each of them, without saving the custom font to a file), and got proper rendering on the ones without the instanced custom font (all objects here are instanced):

This happens between 2 projects which use the same base files. All project settings are default and using the GLES2 driver. Sadly I don't know how to reproduce it in a new project.

[Calinou]

@vicguedez Does this bug occur if you switch to the GLES3 renderer? Also, does this occur with GLES2 if you disable batching in the Project Settings?

[vicguedez]

@Calinou I hadn't tried on GLES3, but it happens there too (just tested it). I also thought of disabling batching but it makes no difference. Scenes always render properly on editor also.

[vicguedez]

@Calinou Changed render thread model to multi-thread and it seems to be fixed in desktop, I have yet to test on Android.

[follower]

FYI there are one or more issues with DynamicFont in relation to caching/updating behaviour. (They're on my unfortunately very long list of issues to write up...)

I've just dumped the caching related issues into a separate issue, in case you want to investigate: #40787 (In part so I don't start to recreate the issue everytime I come back to it. :D )

To start debugging this I'd start by setting (C++) breakpoints on the draw_char() methods in https://github.com/godotengine/godot/blob/aada93afc0ecc699440805ad2574d3e94b7c0abd/scene/resources/dynamic_font.cpp:

• DynamicFont::draw_char()
• DynamicFontAtSize::draw_char()

Then follow the logic to see whether each character is considered "valid" or not & then try to determine...why. :)