from functools import reduce
from select import select
from threading import Thread
import approxeng.input.sys as sys
from approxeng.input.controllers import *
EV_KEY = 1
EV_REL = 2
EV_ABS = 3
[docs]class ControllerResource:
"""
General resource which binds one or more controllers on entry and unbinds the event listening thread on exit.
"""
[docs] def __init__(self, *requirements, print_events=False, **kwargs):
"""
Create a new resource to bind and access one or more controllers. If no additional arguments are supplied this
will find the first controller of any kind enabled by the library. Otherwise the requirements must be provided
as a list of ControllerRequirement
:param ControllerRequirement requirements:
ControllerRequirement instances used, in order, to find and bind controllers. If empty this will
be equivalent to supplying a single unfiltered requirement and will match the first specified controller.
:param bool print_events:
Defaults to False, if set to True then all events picked up by the binder will be printed to stdout. Use
this when you're trying to figure out what events correspond to what axes and buttons!
:param kwargs:
Any addition keyword arguments are passed to the constructors for the controller classes. This is useful
particularly to specify e.g. dead and hot zone ranges on discovery.
:raises ControllerNotFoundError:
If the requirement can't be satisfied, or no requirements are specified but there aren't any controllers.
"""
self.discoveries = find_matching_controllers(*requirements, **kwargs)
self.unbind = None
self.print_events = print_events
def __enter__(self):
"""
Called on entering the resource block, returns the controller passed into the constructor.
"""
self.unbind = bind_controllers(*self.discoveries, print_events=self.print_events)
if len(self.discoveries) == 1:
return self.discoveries[0].controller
else:
return tuple(discovery.controller for discovery in self.discoveries)
def __exit__(self, exc_type, exc_value, traceback):
"""
Called on resource exit, unbinds the controller, removing the listening thread.
"""
self.unbind()
[docs]def bind_controllers(*discoveries, print_events=False):
"""
Bind a controller or controllers to a set of evdev InputDevice instances, starting a thread to keep those
controllers in sync with the state of the hardware.
:param ControllerDiscovery discoveries:
ControllerDiscovery instances specifying the controllers and their associated input devices
:param bool print_events:
Defaults to False, if set to True then all events picked up by this binder will be printed to stdout
:return:
A function which can be used to stop the event reading thread and unbind from the device
"""
discoveries = list(discoveries)
class SelectThread(Thread):
def __init__(self):
Thread.__init__(self, name='evdev select thread')
self.daemon = True
self.running = True
self.device_to_controller_discovery = {}
for discovery in discoveries:
for d in discovery.devices:
self.device_to_controller_discovery[d.fn] = discovery
self.all_devices = reduce(lambda x, y: x + y, [discovery.devices for discovery in discoveries])
def run(self):
for discovery in discoveries:
discovery.controller.device_unique_name = discovery.name
while self.running:
try:
r, w, x = select(self.all_devices, [], [], 0.5)
for fd in r:
active_device = fd
controller_discovery = self.device_to_controller_discovery[active_device.fn]
controller = controller_discovery.controller
controller_devices = controller_discovery.devices
prefix = None
if controller.node_mappings is not None and len(controller_devices) > 1:
try:
prefix = controller.node_mappings[active_device.name]
except KeyError:
pass
for event in active_device.read():
if print_events:
print(event)
if event.type == EV_ABS or event.type == EV_REL:
controller.axes.axis_updated(event, prefix=prefix)
elif event.type == EV_KEY:
# Button event
if event.value == 1:
# Button down
controller.buttons.button_pressed(event.code, prefix=prefix)
elif event.value == 0:
# Button up
controller.buttons.button_released(event.code, prefix=prefix)
except Exception as e:
self.stop(e)
def stop(self, exception=None):
for discovery in discoveries:
discovery.controller.device_unique_name = None
discovery.controller.exception = exception
self.running = False
polling_thread = SelectThread()
# Force an update of the LED and battery system cache
sys.scan_cache(force_update=True)
for device in polling_thread.all_devices:
device.grab()
def unbind():
polling_thread.stop()
for dev in polling_thread.all_devices:
try:
dev.ungrab()
except IOError:
pass
polling_thread.start()
return unbind