setFontCustom bitmap format vs vertical_byte:true - GT24L24A2Y fontchip in F07 fitness tracker

Hello,

was trying to use fonts included in GT24L24A2Y SPI font chip, these chips are often used in smart watches and fitness trackers to provide fonts in many languages. Basically it is relatively normal SPI flash memory with font data is some format. Th structure of fixed width fonts for this chip is documented here https://github.com/RichardBsolut/GT24L24­A2Y I tried to read is as ordinary SPI flash via W25 module into Graphics.createArrayBuffer and it works and the description of offsets and sizes looks correct and I can see letters when I create buffer in correct format. However the buffer must be created with vertical_byte:true parameter. If I put the data directly into setFontCustom it is not looking good because it does not accept this vertical format.

Any idea how to load/convert/rotate such font data in memory via some Espruino graphics/bitmap/image magic so I could then pass the buffer directly to setFontCustom ?

I have attached screenshot how I can load individual letters of https://github.com/RichardBsolut/GT24L24­A2Y#font-clock-4-22x32

And BTW here is video of example code running on this fittness tracker, it is mostly same as P8 smartwatch code linked previously here. This F07 is ~$14-$16 aliexpress item and can be updated to Espruino without taking apart.

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