robolab/src/sensor.py

#!/usr/bin/env python3

import ev3dev.ev3 as ev3
from enum import Enum

'''
add enum for color definitions (type should be tupel of int's).
later onwards compare the idividual readouts like this to determine the color:
RED = (>90, <40, <25)
BLUE = (<25, >75, >90)

Example:
color = (100, 30, 20)
(color[0] > 90 and (color[1], color[2]) < (40, 25))
'''

'''
Calculate brightness/to greyscale from RGB:
http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=5445596
https://en.wikipedia.org/wiki/YUV
Formula:
Y=(0.299 x R) + (0.587 x G) + (0.114 x B);
'''


class Color(tuple, Enum):
    RED = (85, 40, 25)
    BLUE = (25, 70, 85)


class Sensor:
    def __init__(self):
        try:
            self._bumper_l = ev3.TouchSensor("in1")
            self._bumper_r = ev3.TouchSensor("in4")
            self.bumperwaspressed = False
            self._camera = ev3.ColorSensor()
            self._camera.mode = 'RGB-RAW'
            self.RGB = self._camera.bin_data("hhh")
            self._brightness = self._camera.value()
        except OSError:
            print("Error while setting up sensors. Please make sure that everything is plugged in properly.")
        self.lastcolor = None
        self.edgebrightness = None

    def refresh(self):  # do we still want to check if the propper camera/sensor mode is set?
        self.RGB = self._camera.bin_data("hhh")
        self._brightness = self._camera.value()

    def reset(self):
        self.bumperwaspressed = False
        self.lastcolor = None

    def calibrateBrightness(self):
        self.refresh()
        self.edgebrightness = self.getbrightness()

    def checkbumper(self):
        if(self._bumper_l.value() or self._bumper_r.value()):
            self.bumperwaspressed = True

    def getbrightness(self):
        return self._brightness

    def getcolor(self):
        if(self._camera.mode == 'RGB-RAW'):
            if(self.RGB[0] > Color.RED[0] and (self.RGB[1], self.RGB[2]) < (Color.RED[1], Color.RED[2])):
                self.lastcolor = Color.RED
            if(self.RGB[0] < Color.BLUE[0] and (self.RGB[1], self.RGB[2]) > (Color.BLUE[1], Color.BLUE[2])):
                self.lastcolor = Color.BLUE

    def calibrateRGB(self):
        pass