Support absolute mouse coordinates (`adafruit_hid.mouse_absolute`)

[bluepuma77]

We want to control mouse and keyboard on tablets connected via USB to an ESP32 S3 Box (or similar).

adafruit_hid supports keyboard and relative mouse. As in another issue mentioned, sometimes the need arrises to move to absolute positions to know where the mouse really is.

Work-arounds, like moving relative to (-5000;-5000) all the way top left to get to a fixed point, sometimes have issues, like iPads opening some additional layers and windows, sometimes they close again or stay open, therefore no real automation is possible.

It would be great to have adafruit_hid.mouse and additional a real adafruit_hid.mouse_absolute (probably as two separate USB devices) to be able to make relative and absolute moves with a mouse HID.

[jepler]

Check out https://circuitpython-absolute-mouse.readthedocs.io/en/latest/ and see if it's useful for your needs.

[bluepuma77]

@jepler: Can I simply use the v8 package for CircuitPython v9?

[dhalbert]

Yes, the 8.x and 9.x libraries are compatible. Or you could use the .py version.

One reason this is not in adafruit_hid is because we need to keep that library small: it is frozen into some boards with limited flash and we don't have room for more features like absolute mouse or gamepad.

[bluepuma77]

@dhalbert Would it be possible to create a regular and an absolute mouse at the same time?

The example tells to enable keyboard and mouse in boot.py:

import usb_hid
from absolute_mouse.descriptor import device

usb_hid.enable((usb_hid.Device.KEYBOARD, device))

Can I enable 3 HID devices: keyboard, regular mouse and absolute mouse? How?

[dhalbert]

Yes, you can do

usb_hid.enable((usb_hid.Device.KEYBOARD, usb_hid.Device.MOUSE, device))

But, you have to be a little trickier when passing a list of devices to adafruit_hid.mouse.Mouse() and absolute_mouse.Mouse(). Both mouse devices have the same Usage Page and Usage. They both have this in their report descriptors:

        0x05, 0x01,    # Usage Page (Generic Desktop)
        0x09, 0x02,  # Usage (Mouse)

Usage Page = 1, and Usage = 2

Normally you would do Mouse(usb_hid.devices). But that looks for the first device with the Usage Page and Uage values expected. So instead of passing the whole usb_hid.devices, just pass a tuple or list with the device you mean to use. If you are using the exact device list I gave above, the keyboard will be usb_hid.devices[0], the relative mouse will be usb_hid.devices[1], and the absolute mouse will be usb_hid.devices[2]. So do something like:

absolute_mouse = absolute_mouse.Mouse((usb_hid.devices[2],))  # pass tuple just containing the absolute mouse device

[bluepuma77]

@dhalbert: When using v8 files from release and

from absolute_mouse.descriptor import device

I do get an error:

incompatible .mpy file

Can I just copy __init__.py and descriptor.py into /lib/absolute_mouse on the device?

[dhalbert]

Yes, it's fine to use the .py versions.

[bluepuma77]

Awesome, it works! I can move the mouse absolute on iPad. Just copied the two .py files into the /lib/absolute_mouse folder and added the initialization in boot.py from the example.

Thanks @dhalbert @jepler

It would be great if the HID doc could hint to this, even though it's not in the official package.

[bluepuma77]

Had to apply the patch to make m.click() work.