vis_params.py

# -*- coding: utf-8 -*-
# GIAnT Group Interaction Analysis Toolkit
# Copyright (C) 2017 Interactive Media Lab Dresden
# 
# This program 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.
# 
# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

from libavg import avg


class VisParams(avg.Publisher):
    CHANGED = avg.Publisher.genMessageID()
    IS_PLAYING = avg.Publisher.genMessageID()

    MIN_SMOOTHNESS_FACTOR = 0.01
    MAX_SMOOTHNESS_FACTOR = 1.

    __highlight_time = 0
    __zoom_strength = 0.15

    def __init__(self, session):
        super(VisParams, self).__init__()
        self.__is_playing = False
        self.__time_interval = [0, session.duration]
        self.publish(VisParams.CHANGED)
        self.publish(VisParams.IS_PLAYING)

        self.__smoothness_factor = self.MAX_SMOOTHNESS_FACTOR/2.
        self.__users_visible = [True]*session.num_users
        self.__duration = session.duration

    def get_time_interval(self):
        return self.__time_interval

    def get_time_duration(self):
        return self.__time_interval[1] - self.__time_interval[0]

    def zoom_in_at(self, fraction_in_timeframe):
        point = self.__time_interval[0] + fraction_in_timeframe * (self.__time_interval[1] - self.__time_interval[0])
        self.__time_interval[0] = point - (point - self.__time_interval[0]) * (1 - self.__zoom_strength)
        self.__time_interval[1] = point + (self.__time_interval[1] - point) * (1 - self.__zoom_strength)
        self.notify()

    def zoom_out_at(self, fraction_in_timeframe):
        time_range = [0, self.__duration]
        if self.__time_interval == time_range:
            return
        point = self.__time_interval[0] + fraction_in_timeframe * (self.__time_interval[1] - self.__time_interval[0])
        self.__time_interval[0] -= (point - self.__time_interval[0]) / ((1 / self.__zoom_strength) - 1)
        self.__time_interval[1] += (self.__time_interval[1] - point) / ((1 / self.__zoom_strength) - 1)

        if self.__time_interval[0] < time_range[0]:
            self.__time_interval[0] = time_range[0]

        if self.__time_interval[1] > time_range[1]:
            self.__time_interval[1] = time_range[1]
        self.notify()

    def shift_time(self, forwards, amount=-1):
        if amount == -1:
            amount = (self.__time_interval[1] - self.__time_interval[0]) * self.__zoom_strength / 2
        if forwards:
            shift_amount = amount
        else:
            shift_amount = -amount

        if self.__time_interval[0] + shift_amount < 0:
            shift_amount = 0 - self.__time_interval[0]
        if self.__time_interval[1] + shift_amount > self.__duration:
            shift_amount = self.__duration - self.__time_interval[1]

        self.__time_interval[0] += shift_amount
        self.__time_interval[1] += shift_amount
        self.__highlight_time += shift_amount
        self.notify()

    def set_time_interval(self, interval):
        self.__time_interval = list(interval)
        self.notify()

    def notify(self):
        self.notifySubscribers(VisParams.CHANGED, [self])

    def get_user_visible(self, i):
        return self.__users_visible[i]

    def set_user_visible(self, i, visible):
        self.__users_visible[i] = visible
        self.notify()

    def set_smoothness_factor(self, value):
        self.__smoothness_factor = value

    def get_smoothness_factor(self):
        return self.__smoothness_factor

    @classmethod
    def get_user_color(cls, userid):
        # User colors are specified in CIE Lch color space.
        # This allows us to easily pick four colors that have the same perceptual brightness and saturation,
        # but differing hue.
        user_grey = (60, 0, 0)
        user_hues = (40, 130, 220, 310)
        if userid == -1:
            l, c, h = user_grey
        else:
            l = 60
            c = 90
            h = user_hues[userid]
        return avg.Color.fromLch(l, c, h)

    def __set_highlight_time(self, time):
        self.__highlight_time = time

    def __get_highlight_time(self):
        return self.__highlight_time
    highlight_time = property(__get_highlight_time, __set_highlight_time)

    def __set_is_playing(self, is_playing):
        self.__is_playing = is_playing
        self.notifySubscribers(VisParams.IS_PLAYING, [self.__is_playing])

    def __get_is_playing(self):
        return self.__is_playing
    is_playing = property(__get_is_playing, __set_is_playing)