wasp-os/wasp/apps/chrono.py
Daniel Thompson 726d5c8554 apps: chrono: Implement a simple analogue watch face
Signed-off-by: Daniel Thompson <daniel@redfelineninja.org.uk>
2020-12-27 09:13:49 +00:00

103 lines
2.9 KiB
Python

# SPDX-License-Identifier: LGPL-3.0-or-later
# Copyright (C) 2020 Daniel Thompson
"""Analogue clock
~~~~~~~~~~~~~~~~~
Shows the time as a traditional watch face together with a battery meter.
.. figure:: res/ChronoApp.png
:width: 179
Screenshot of the analogue clock application
"""
import wasp
class ChronoApp():
"""Simple analogue clock application.
"""
NAME = 'Chrono'
def foreground(self):
"""Activate the application.
Configure the status bar, redraw the display and request a periodic
tick callback every second.
"""
wasp.system.bar.clock = False
self._draw(True)
wasp.system.request_tick(1000)
def sleep(self):
"""Prepare to enter the low power mode.
:returns: True, which tells the system manager not to automatically
switch to the default application before sleeping.
"""
return True
def wake(self):
"""Return from low power mode.
Time will have changes whilst we have been asleep so we must
udpate the display (but there is no need for a full redraw because
the display RAM is preserved during a sleep.
"""
self._draw()
def tick(self, ticks):
"""Periodic callback to update the display."""
self._draw()
def _draw(self, redraw=False):
"""Draw or lazily update the display.
The updates are as lazy by default and avoid spending time redrawing
if the time on display has not changed. However if redraw is set to
True then a full redraw is be performed.
"""
draw = wasp.watch.drawable
hi = wasp.system.theme('accent-hi')
mid = wasp.system.theme('accent-mid')
lo = wasp.system.theme('accent-lo')
if redraw:
now = wasp.watch.rtc.get_localtime()
# Clear the display and draw that static parts of the watch face
draw.fill()
# Redraw the status bar
wasp.system.bar.draw()
# Draw the dividers
draw.set_color(mid)
for theta in range(12):
draw.polar(120, 120, theta * 360 // 12, 111, 119, 2)
self._hh = 0
self._mm = 0
else:
now = wasp.system.bar.update()
if not now or self._mm == now[4]:
# Skip the update
return
# Undraw old time
hh = (30 * (self._hh % 12)) + (self._mm / 2)
mm = 6 * self._mm
draw.polar(120, 120, hh, 5, 80, 5, 0)
draw.polar(120, 120, mm, 5, 110, 3, 0)
# Record the minute that is currently being displayed
self._hh = now[3]
self._mm = now[4]
# Draw the new time
hh = (30 * (self._hh % 12)) + (self._mm / 2)
mm = 6 * self._mm
draw.polar(120, 120, hh, 5, 80, 5, hi)
draw.polar(120, 120, hh, 5, 60, 3, lo)
draw.polar(120, 120, mm, 5, 110, 3, hi)