I have a Wileyfox Spark, for lovers of it, you surely know it comes with CyanogenMod13 OS as it's stock. But you know very well how one might want a more decent Nougat or Oreo based CM14 or CM15 or even AOSP7.x.x. I have all the ROMs I need in the device and a ready TWRP 3.2.0, a full backup of the stock images from boot.img to userdata.img. Installing the new ROMs work fine despite the fact that on any custom OS I have tried, the device boot's up with the boot animation 180° rotated. This continues to bootup and it only returns normal if I turn display off and on. Flashing the stock boot.img solves the issue of rotation but since the ROM isn't stock, it just Bootloops infinitely. I'm not a Kernel developer and neither do I have enough knowledge on how to do. I suggest somebody with a workaround for this issue. I don't like the stock OS which I'm forced to return to.
If you can bear with having to turn screen off/on once the device had booted up, and just want the bootanimation to look normal, that's quite easy - just edit the bootanimation itself to make it upside-down.
- Grab and extract
- Rotate every extracted image by 180 degrees.
- Recompress the extracted files, keep the structure (compare with the original if necessary), and choose "storage" when asked about compression level (any actual compression will prevent Android from reading the file).
- Place the modified file back to where it was and set proper permissions.