Mouse Cursor Bitmap Improvements

[relic-se]

Currently, the default value of the cursor_image parameter within adafruit_usb_host_mouse.find_and_init_boot_mouse assumes that the application is running within Fruit Jam OS. To improve the usability of this library within other scenarios, the "mouse_cursor.bmp" should be included within this library and the find_and_init_boot_mouse method should be able to automatically determine its absolute path.

In case the user doesn't actually want to use this library with displayio, they should be able to disable the bitmap altogether and obtain x and y coordinates as a relative point from the initial position of the mouse without the use of a displayio.TileGrid object.

Here is my proposed implementation of the cursor_image parameter:

• cursor_image="...", load the bitmap and generate the TileGrid object as is currently implemented
• cursor_image=None, determine the local bitmap file absolute path and continue normal operation
• cursor_image=False, create the BootMouse object without any displayio initialization

The x and y position of the mouse could be access using basic checks, ie: return self.tilegrid.x if self.tilegrid else self._x, or the position could be managed by class-level private variables regardless if a TileGrid object was provided.

Note: Is there a limitation with circup libraries about distributing non-mpy files? Would it be possible to load bitmap data as a bytes object instead?

[FoamyGuy]

I think that circup can distribute non-mpy / py files. I believe it's used by the .bin file here: https://github.com/adafruit/Adafruit_CircuitPython_PyCamera/tree/main/adafruit_pycamera. I'm not sure if there is a file extension filter on it though, so not certain if .bmp will work but think there is a decent chance it will, or only small tweak needed if not.