How can I access tablet pen data via Python?

Question

I need to access a windows tablet pen data (such as the surface) via Python. I mainly need the position, pressure, and tilt values.

I know how to access the Wacom pen data but the windows pen is different.

There is a Python library named Kivy that can handle multi-touch but it recognizes my pen as a finger (WM_TOUCH) and not as a pen (WM_PEN).

This is my Kivy code (that doesnt report pressure and tilt):

 from kivy.app import App
 from kivy.uix.widget import Widget

class TouchInput(Widget):

def on_touch_down(self, touch):
    print(touch)
def on_touch_move(self, touch):
    print(touch)
def on_touch_up(self, touch):
    print("RELEASED!",touch)

class SimpleKivy4(App):

def build(self):
    return TouchInput()

There is a wonderful processing library named Tablet that only works with the Wacom tablet with a simple API (e.g., tablet.getPressure())

I need something like this.

Suppliant

Answer 1

if you want to see the devices:

import pyglet
pyglet.input.get_devices()

if you want to see the devices controls:

tablets = pyglet.input.get_devices() #tablets is a list of input devices
tablets[0].get_controls() #get_controls gives a list of possible controls of the device  

And now to get the data. I have a xp-pen g640 tablet and don't have tilt sensor, but if yours have it it will be easy to modify the code:

if tablets:
    print('Tablets:')
    for i, tablet in enumerate(tablets):
        print('  (%d) %s' % (i , tablet.name))
i = int(input('type the index of the tablet.'))

device = tablets[i]
controls = device.get_controls()
df = pd.DataFrame()
window = pyglet.window.Window(1020, 576)

# Here you will have to write a line like "control_tilt_x = controls[j]" where j is
# the controls list index of the tilt control.
control_presion = controls[7]
Button = controls[3]
control_x =controls[5]
control_y =controls[6]
control_punta = controls[4]
control_alcance = controls [0]
name = tablets[9].name

try:
    canvas = device.open(window)
except pyglet.input.DeviceException:
    print('Failed to open tablet %d on window' % index)

print('Opened %s' % name)

    
@control_presion.event
def on_change(presion):
    global df   
    df_temp = pd.DataFrame({'x':[control_x.value/(2**15)],
                           'y':[control_y.value/(2**16)],
                           'p':[control_presion.value/8],
                           't':[time.time()]})
    df = pd.concat([df,df_temp])
          
pyglet.app.run()

Dominicdominica

Answer 2

This solution works for me, adapted to Python 3 from here.

What works: pen, eraser, pen buttons, both pressure sensors.

Install pyglet library first: pip install pyglet. Then use code:

import pyglet

window = pyglet.window.Window()
tablets = pyglet.input.get_tablets()
canvases = []

if tablets:
    print('Tablets:')
    for i, tablet in enumerate(tablets):
        print('  (%d) %s' % (i + 1, tablet.name))
    print('Press number key to open corresponding tablet device.')
else:
    print('No tablets found.')

@window.event
def on_text(text):
    try:
        index = int(text) - 1
    except ValueError:
        return

    if not (0 <= index < len(tablets)):
        return

    name = tablets[i].name

    try:
        canvas = tablets[i].open(window)
    except pyglet.input.DeviceException:
        print('Failed to open tablet %d on window' % index)

    print('Opened %s' % name)

    @canvas.event
    def on_enter(cursor):
        print('%s: on_enter(%r)' % (name, cursor))

    @canvas.event
    def on_leave(cursor):
        print('%s: on_leave(%r)' % (name, cursor))

    @canvas.event
    def on_motion(cursor, x, y, pressure, a, b):  # if you know what "a" and "b" are tell me (tilt?)
        print('%s: on_motion(%r, x=%r, y=%r, pressure=%r, %s, %s)' % (name, cursor, x, y, pressure, a, b))

@window.event
def on_mouse_press(x, y, button, modifiers):
    print('on_mouse_press(%r, %r, %r, %r' % (x, y, button, modifiers))

@window.event
def on_mouse_release(x, y, button, modifiers):
    print('on_mouse_release(%r, %r, %r, %r' % (x, y, button, modifiers))

pyglet.app.run()

Criticaster

Thanks. I tried your code but when I move the surface pen, I only get mouse events (pressed, released) and no motion events, plus, I get "no tablet found" No tablets found. on_mouse_press(448, 150, 1, 16 on_mouse_release(273, 324, 1, 16 on_mouse_press(252, 318, 1, 16 on_mouse_release(237, 151, 1, 16 – Suppliant

@RoiYozevitch, "No tablets" means bad news. Maybe you need drivers, or your device is too new. I use Wacom Bamboo. – Criticaster

It's working for me. However, it's interesting that after each pen event I get either 0 or 1 printed (depends whether the pen touched the tablet). I even disabled all prints, and those 0 and 1s continued to print... – Trisaccharide