virtualWorld.py

## Credit to Paul McWhorter

## This program reads data over the serial port
## from that arduino. You have to read an entire line of data
## and then you have to parse it into different number values
## Then those R, G, B numbers are used to make the color of
## a visual object in python change.

import serial #import serial library
from visual import * #import vPython library

MyScene=display(title='My Virtual World') #Create your scene and give it a title.

MyScene.width=800  #We can set the dimension of your visual box. 800X800 pixels works well on my screen
MyScene.height= 800
MyScene.autoscale=False #We want to set the range of the scene manually for better control. Turn autoscale off
MyScene.range = (12,12,12) #Set range of your scene to be 12 inches by 12 inches by 12 inches. 
target=box(length=.1, width=10,height=5, pos=(-6,0,0)) #Create the object that will represent your target (which is a colored card for our project)
myBoxEnd=box(length=.1, width=10,height=5, pos=(-8.5,0,0)) #This object is the little square that is the back of the ultrasonic sensor
myTube2=cylinder(color=color.blue, pos=(-8.5,0,-2.5), radius=1.5,length=2.5 ) #One of the 'tubes' in the front of the ultrasonic sensor
myTube3=cylinder(color=color.blue, pos=(-8.5,0,2.5), radius=1.5,length=2.5 )  #Other tube
myBall=sphere(color=color.red, radius=.3)

sensorData= serial.Serial('com11',115200) # Create senorData object to read serial port data coming from arduino

while True: #This is a while loop that will loop forever, since True is always True.
    
    rate(25) #We need to tell Vpython how fast to go through the loop. 25 times a second works pretty well
    while(sensorData.inWaiting()==0): # Wait here untill there is data on the Serial Port
        pass                          # Do nothing, just loop until data arrives
    textline = sensorData.readline()     # read the entire line of text
    dataNums=textline.split(',')       #Remember to split the line of text into an array at the commas
    red=float(dataNums[0])             # Make variables for Red, Blue, Green. Remember
    green=float(dataNums[1])            # the array was read as text, so must be converted
    blue=float(dataNums[2])           # to numbers with float command
    dist=float(dataNums[3])            # last number in the list is the distance

    blue=blue*.7                      #On my sensor, blue is always a little too strong, so I tone it down a little
    if (dist>=1.5 and dist<=2.25):    #only change color or target if target is between 1.5 and 2.25 inches from sensor
        target.color=(red/255., green/255., blue/255.) #This keeps color from flickering.

    target.pos=vector(-6 + dist,0,0)  #Adjust the position of the target object to match the distance of the real target from the real sensor