input-remapper/keymapper/utils.py
2021-11-21 21:45:02 +01:00

242 lines
6.5 KiB
Python

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# key-mapper - GUI for device specific keyboard mappings
# Copyright (C) 2021 sezanzeb <proxima@sezanzeb.de>
#
# This file is part of key-mapper.
#
# key-mapper is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# key-mapper is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with key-mapper. If not, see <https://www.gnu.org/licenses/>.
"""Utility functions."""
import math
import sys
import evdev
from evdev.ecodes import (
EV_KEY,
EV_ABS,
ABS_X,
ABS_Y,
ABS_RX,
ABS_RY,
EV_REL,
REL_WHEEL,
REL_HWHEEL,
)
from keymapper.logger import logger
from keymapper.config import BUTTONS
# other events for ABS include buttons
JOYSTICK = [
evdev.ecodes.ABS_X,
evdev.ecodes.ABS_Y,
evdev.ecodes.ABS_RX,
evdev.ecodes.ABS_RY,
]
# drawing table stylus movements
STYLUS = [
(EV_ABS, evdev.ecodes.ABS_DISTANCE),
(EV_ABS, evdev.ecodes.ABS_TILT_X),
(EV_ABS, evdev.ecodes.ABS_TILT_Y),
(EV_KEY, evdev.ecodes.BTN_DIGI),
(EV_ABS, evdev.ecodes.ABS_PRESSURE),
]
# a third of a quarter circle, so that each quarter is divided in 3 areas:
# up, left and up-left. That makes up/down/left/right larger than the
# overlapping sections though, maybe it should be 8 equal areas though, idk
JOYSTICK_BUTTON_THRESHOLD = math.sin((math.pi / 2) / 3 * 1)
PRESS = 1
# D-Pads and joysticks can have a second press event, which moves the knob to the
# opposite side, reporting a negative value
PRESS_NEGATIVE = -1
RELEASE = 0
def sign(value):
"""Return -1, 0 or 1 depending on the input value."""
if value > 0:
return 1
if value < 0:
return -1
return 0
def classify_action(event, abs_range=None):
"""Fit the event value to one of PRESS, PRESS_NEGATIVE or RELEASE
A joystick that is pushed to the very side will probably send a high value, whereas
having it close to the middle might send values close to 0 with some noise. A value
of 1 is usually noise or from touching the joystick very gently and considered in
resting position.
"""
if event.type == EV_ABS and event.code in JOYSTICK:
if abs_range is None:
logger.error(
"Got %s, but abs_range is %s",
(event.type, event.code, event.value),
abs_range,
)
return event.value
# center is the value of the resting position
center = (abs_range[1] + abs_range[0]) / 2
# normalizer is the maximum possible value after centering
normalizer = (abs_range[1] - abs_range[0]) / 2
threshold = normalizer * JOYSTICK_BUTTON_THRESHOLD
triggered = abs(event.value - center) > threshold
return sign(event.value - center) if triggered else 0
# non-joystick abs events (triggers) usually start at 0 and go up to 255,
# but anything that is > 0 was safe to be treated as pressed so far
return sign(event.value)
def is_key_down(action):
"""Is this action a key press."""
return action in [PRESS, PRESS_NEGATIVE]
def is_key_up(action):
"""Is this action a key release."""
return action == RELEASE
def is_wheel(event):
"""Check if this is a wheel event."""
return event.type == EV_REL and event.code in [REL_WHEEL, REL_HWHEEL]
def will_report_key_up(event):
"""Check if the key is expected to report a down event as well."""
return not is_wheel(event)
def should_map_as_btn(event, mapping, gamepad):
"""Does this event describe a button that is or can be mapped.
If a new kind of event should be mappable to buttons, this is the place
to add it.
Especially important for gamepad events, some of the buttons
require special rules.
Parameters
----------
event : evdev.InputEvent
mapping : Mapping
gamepad : bool
If the device is treated as gamepad
"""
if (event.type, event.code) in STYLUS:
return False
is_mousepad = event.type == EV_ABS and 47 <= event.code <= 61
if is_mousepad:
return False
if event.type == EV_ABS:
if event.code == evdev.ecodes.ABS_MISC:
# what is that even supposed to be.
# the intuos 5 spams those with every event
return False
if event.code in JOYSTICK:
if not gamepad:
return False
l_purpose = mapping.get("gamepad.joystick.left_purpose")
r_purpose = mapping.get("gamepad.joystick.right_purpose")
if event.code in [ABS_X, ABS_Y] and l_purpose == BUTTONS:
return True
if event.code in [ABS_RX, ABS_RY] and r_purpose == BUTTONS:
return True
else:
# for non-joystick buttons just always offer mapping them to
# buttons
return True
if is_wheel(event):
return True
if event.type == EV_KEY:
# usually all EV_KEY events are allright, except for
if event.code == evdev.ecodes.BTN_TOUCH:
return False
return True
return False
def get_abs_range(device, code=ABS_X):
"""Figure out the max and min value of EV_ABS events of that device.
Like joystick movements or triggers.
"""
# since input_device.absinfo(EV_ABS).max is too new for (some?) ubuntus,
# figure out the max value via the capabilities
capabilities = device.capabilities(absinfo=True)
if EV_ABS not in capabilities:
return None
absinfo = [
entry[1]
for entry in capabilities[EV_ABS]
if (
entry[0] == code
and isinstance(entry, tuple)
and isinstance(entry[1], evdev.AbsInfo)
)
]
if len(absinfo) == 0:
logger.warn(
'Failed to get ABS info of "%s" for key %d: %s', device, code, capabilities
)
return None
absinfo = absinfo[0]
return absinfo.min, absinfo.max
def get_max_abs(device, code=ABS_X):
"""Figure out the max value of EV_ABS events of that device.
Like joystick movements or triggers.
"""
abs_range = get_abs_range(device, code)
return abs_range and abs_range[1]
def is_service():
return sys.argv[0].endswith("key-mapper-service")