sugar-toolkit-gtk3/sugar/graphics/animator.py
2007-04-16 11:40:28 +02:00

95 lines
2.8 KiB
Python

# Copyright (C) 2007, Red Hat, Inc.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
import time
import gobject
EASE_OUT_EXPO = 0
EASE_IN_EXPO = 1
class Animator(gobject.GObject):
__gsignals__ = {
'completed': (gobject.SIGNAL_RUN_FIRST,
gobject.TYPE_NONE, ([])),
}
def __init__(self, time, fps, easing=EASE_OUT_EXPO):
gobject.GObject.__init__(self)
self._animations = []
self._time = time
self._interval = 1.0 / fps
self._easing = easing
self._timeout_sid = 0
def add(self, animation):
self._animations.append(animation)
def remove_all(self):
self.stop()
self._animations = []
def start(self):
if self._timeout_sid:
self.stop()
self._start_time = time.time()
self._timeout_sid = gobject.timeout_add(
int(self._interval * 1000), self._next_frame_cb)
def stop(self):
if self._timeout_sid:
gobject.source_remove(self._timeout_sid)
self._timeout_sid = 0
self.emit('completed')
def _next_frame_cb(self):
current_time = min(self._time, time.time() - self._start_time)
current_time = max(current_time, 0.0)
for animation in self._animations:
animation.do_frame(current_time, self._time, self._easing)
if current_time == self._time:
self.stop()
return False
else:
return True
class Animation(object):
def __init__(self, start, end):
self.start = start
self.end = end
def do_frame(self, time, duration, easing):
start = self.start
change = self.end - self.start
if time == duration:
# last frame
frame = self.end
else:
if easing == EASE_OUT_EXPO:
frame = change * (-pow(2, -10 * time/duration) + 1) + start;
elif easing == EASE_IN_EXPO:
frame = change * pow(2, 10 * (time / duration - 1)) + start;
self.next_frame(frame)
def next_frame(self, frame):
pass