def event_loop(configs, joy_map, tty_fd):
event = SDL_Event()
# keep of dict of active joystick devices as a dict of
# instance_id -> (config_id, SDL_Joystick object)
active_devices = {}
# keep an event queue populated with the current active inputs
# indexed by joystick index, input type and input index
# the values consist of:
# - the event list (as taked from the event configuration)
# - the number of times event was emitted (repeated)
# - the last time when the event was fired
# e.g. { event_hash -> ([event_list], repeat_no, last_fire_time) }
event_queue = {}
# keep track of axis previous values
axis_prev_values = {}
def handle_new_input(e: SDL_Event, axis_norm_value: int = 0) -> bool:
"""
Event handling for button press/hat movement/axis movement
Only needed when an new input is present
Returns True when 'event_queue' is modified with a new event
"""
dev_index = active_devices[event.jdevice.which][0]
if e.type == SDL_JOYBUTTONDOWN:
mapped_events = configs[dev_index].get_btn_event(
event.jbutton.button)
event_index = f'{dev_index}_btn{event.jbutton.button}'
elif e.type == SDL_JOYHATMOTION:
mapped_events = configs[dev_index].get_hat_event(
event.jhat.hat, event.jhat.value)
event_index = f'{dev_index}_hat{event.jhat.hat}'
elif e.type == SDL_JOYAXISMOTION and axis_norm_value != 0:
mapped_events = configs[dev_index].get_axis_event(
event.jaxis.axis, axis_norm_value)
event_index = f'{dev_index}_axis{event.jaxis.axis}'
if mapped_events is not None:
event_queue[event_index] = [mapped_events, 0, SDL_GetTicks()]
return True
return False
running = True
while running:
input_started = False
while SDL_PollEvent(byref(event)):
if event.type == SDL_QUIT:
running = False
break
if event.type == SDL_JOYDEVICEADDED:
stick = joystick.SDL_JoystickOpen(event.jdevice.which)
name = joystick.SDL_JoystickName(stick).decode('utf-8')
guid = create_string_buffer(33)
joystick.SDL_JoystickGetGUIDString(
joystick.SDL_JoystickGetGUID(stick), guid, 33)
LOG.debug(
f'Joystick #{joystick.SDL_JoystickInstanceID(stick)} {name} added'
)
conf_found = False
# try to find a configuration for the joystick
for key, dev_conf in enumerate(configs):
if dev_conf.name == str(
name) or dev_conf.guid == guid.value.decode():
# Add the matching joystick configuration to the watched list
active_devices[joystick.SDL_JoystickInstanceID(
stick)] = (key, stick)
LOG.debug(
f'Added configuration for known device {configs[key]}'
)
conf_found = True
break
# add the default configuration for unknown/un-configured joysticks
if not conf_found:
LOG.debug(
f'Un-configured device "{str(name)}", mapped using generic mapping'
)
active_devices[joystick.SDL_JoystickInstanceID(stick)] = (
0, stick)
# if the device has axis inputs, initialize to zero their initial position
if joystick.SDL_JoystickNumAxes(stick) > 0:
axis_prev_values[joystick.SDL_JoystickInstanceID(
stick)] = [
0
for x in range(joystick.SDL_JoystickNumAxes(stick))
]
continue
if event.jdevice.which not in active_devices:
continue
else:
dev_index = active_devices[event.jdevice.which][0]
if event.type == SDL_JOYDEVICEREMOVED:
joystick.SDL_JoystickClose(
active_devices[event.jdevice.which][1])
active_devices.pop(event.jdevice.which, None)
axis_prev_values.pop(event.jdevice.which, None)
LOG.debug(f'Removed joystick #{event.jdevice.which}')
if event.type == SDL_JOYBUTTONDOWN:
input_started = handle_new_input(event)
if event.type == SDL_JOYBUTTONUP:
event_queue.pop(f'{dev_index}_btn{event.jbutton.button}', None)
if event.type == SDL_JOYHATMOTION:
if event.jhat.value != SDL_HAT_CENTERED:
input_started = handle_new_input(event)
else:
event_queue.pop(f'{dev_index}_hat{event.jhat.hat}', None)
if event.type == SDL_JOYAXISMOTION:
# check if the axis value went over the deadzone threshold
if (abs(event.jaxis.value) > JS_AXIS_DEADZONE) \
!= (abs(axis_prev_values[event.jdevice.which][event.jaxis.axis]) > JS_AXIS_DEADZONE):
# normalize the axis value to the movement direction or stop the input
if abs(event.jaxis.value) <= JS_AXIS_DEADZONE:
event_queue.pop(f'{dev_index}_axis{event.jaxis.axis}',
None)
else:
if event.jaxis.value < 0:
axis_norm_value = -1
else:
axis_norm_value = 1
input_started = handle_new_input(
event, axis_norm_value)
# store the axis current values for tracking
axis_prev_values[event.jdevice.which][
event.jaxis.axis] = event.jaxis.value
# process the current events in the queue
if len(event_queue):
emitted_events = filter_active_events(event_queue)
if len(emitted_events):
LOG.debug(f'Events emitted: {emitted_events}')
# send the events mapped key code(s) to the terminal
for k in emitted_events:
if k in joy_map:
for c in joy_map[k]:
fcntl.ioctl(tty_fd, termios.TIOCSTI, c)
SDL_Delay(JS_POLL_DELAY)
def test_SDL_JoystickInstanceID(self):
for index in range(self.jcount):
stick = joystick.SDL_JoystickOpen(index)
ret = joystick.SDL_JoystickInstanceID(stick)
assert ret > 0
joystick.SDL_JoystickClose(stick)