[mark9064]

Requires #2372, #2391

• Fonts load much faster. With LittleFS upgrade + fixes #2330, the G7710 watchface should load in about 30ms versus the current 250-400ms (10x speedup)
  • Basically it is no longer noticeable whether fonts are on the external flash or not
• Fonts use less memory when loaded as they are in one large allocation
• Saves ~2K flash size (LVGL font loader eliminated)
• Fonts changed to use smart pointers so they deallocate themselves

Closes #2197, #2132

@tituscmd you might be interested in trying this :)

This works by compiling the fonts separately at compile time. The data sections (i.e. the structs) are pulled out and serialised to a file, and all the internal pointers are set to their offsets within the file. This makes loading the font extremely easy: allocate a block of memory the size of the file, copy the entire file to that memory, and then fix the pointers inside by adding the address of the memory to all of them. This allows fonts to be loaded with minimal overhead.

[github-actions]

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[tituscmd]

Very nice! I am indeed interested in this :)

I'll put this PR on the list of stuff I wanna tackle once I've got the free time again.
When that time comes, I'll report whatever I can!

[mark9064]

Looks like CI won't work as it depends on the updated container. I promise it builds :P

(The build requires pyelftools now, but the current build container doesn't have it)

[mark9064]

Numerals exposed an issue with the kerning support missing a FixPointer call

Also it was a good time to handle memory allocation failure gracefully. Now a fallback font will be loaded instead (the small system font) so information is still visible (though probably smaller than intended). This avoids font corruption or crashes that are currently seen when LVGL faces low memory