[Visualpython-users] Vpython ' box ' rotation function

Dear all,

I have the following python code which reads COM port and and graphical
object is rotated by the data coming from COM port.

# Test for Razor 9DOF IMU AHRS
# VPhyton, pyserial and pywin modules

from visual import *
import serial
import string
import math

from time import time

grad2rad = 3.141592/180.0

# Check your COM port and baud rate
ser = serial.Serial(port='COM4',baudrate=57600, timeout=1)

# Main scene
scene=display(title="9DOF Razor IMU test")
scene.range=(1.2,1.2,1.2)
#scene.forward = (0,-1,-0.25)
scene.forward = (1,0,-0.25)
scene.up=(0,0,1)

# Second scene (Roll, Pitch, Yaw)
scene2 = display(title='9DOF Razor IMU test',x=0, y=0, width=500,
height=200,center=(0,0,0), background=(0,0,0))
scene2.range=(1,1,1)
scene.width=500
scene.y=200

scene2.select()
#Roll, Pitch, Yaw
cil_roll =
cylinder(pos=(-0.4,0,0),axis=(0.2,0,0),radius=0.01,color=color.red)
cil_roll2 =
cylinder(pos=(-0.4,0,0),axis=(-0.2,0,0),radius=0.01,color=color.red)
cil_pitch =
cylinder(pos=(0.1,0,0),axis=(0.2,0,0),radius=0.01,color=color.green)
cil_pitch2 =
cylinder(pos=(0.1,0,0),axis=(-0.2,0,0),radius=0.01,color=color.green)
#cil_course =
cylinder(pos=(0.6,0,0),axis=(0.2,0,0),radius=0.01,color=color.blue)
#cil_course2 =
cylinder(pos=(0.6,0,0),axis=(-0.2,0,0),radius=0.01,color=color.blue)
arrow_course = arrow(pos=(0.6,0,0),color=color.cyan,axis=(-0.2,0,0),
shaftwidth=0.02, fixedwidth=1)

#Roll,Pitch,Yaw labels
label(pos=(-0.4,0.3,0),text="Roll",box=0,opacity=0)
label(pos=(0.1,0.3,0),text="Pitch",box=0,opacity=0)
label(pos=(0.55,0.3,0),text="Yaw",box=0,opacity=0)
label(pos=(0.6,0.22,0),text="N",box=0,opacity=0,color=color.yellow)
label(pos=(0.6,-0.22,0),text="S",box=0,opacity=0,color=color.yellow)
label(pos=(0.38,0,0),text="W",box=0,opacity=0,color=color.yellow)
label(pos=(0.82,0,0),text="E",box=0,opacity=0,color=color.yellow)
label(pos=(0.75,0.15,0),height=7,text="NE",box=0,color=color.yellow)
label(pos=(0.45,0.15,0),height=7,text="NW",box=0,color=color.yellow)
label(pos=(0.75,-0.15,0),height=7,text="SE",box=0,color=color.yellow)
label(pos=(0.45,-0.15,0),height=7,text="SW",box=0,color=color.yellow)

L1 = label(pos=(-0.4,0.22,0),text="-",box=0,opacity=0)
L2 = label(pos=(0.1,0.22,0),text="-",box=0,opacity=0)
L3 = label(pos=(0.7,0.3,0),text="-",box=0,opacity=0)

# Main scene objects
scene.select()
# Reference axis (x,y,z)
arrow(color=color.green,axis=(1,0,0), shaftwidth=0.02, fixedwidth=1)
arrow(color=color.green,axis=(0,-1,0), shaftwidth=0.02 , fixedwidth=1)
arrow(color=color.green,axis=(0,0,-1), shaftwidth=0.02, fixedwidth=1)
# labels
label(pos=(0,0,0.8),text="9DOF Razor IMU test",box=0,opacity=0)
label(pos=(1,0,0),text="X",box=0,opacity=0)
label(pos=(0,-1,0),text="Y",box=0,opacity=0)
label(pos=(0,0,-1),text="Z",box=0,opacity=0)
# IMU object
platform = box(length=1, height=0.05, width=1, color=color.red)
p_line = box(length=1,height=0.08,width=0.1,color=color.yellow)
plat_arrow = arrow(color=color.green,axis=(1,0,0), shaftwidth=0.06,
fixedwidth=1)


f = open("Serial"+str(time())+".txt", 'w')

roll=0
pitch=0
yaw=0
while 1:
    line = ser.readline()
    line = line.replace("!ANG:","")   # Delete "!ANG:"
    print line
    f.write(line)                     # Write to the output log file
    words = string.split(line,",")    # Fields split
    if len(words) >2:
        try:
            roll = float(words[0])*grad2rad
            pitch = float(words[1])*grad2rad
            yaw = float(words[2])*grad2rad
        except:
            print "Invalid line"
           # roll=0
           # pitch=0
           # yaw=0
           # words[0]=0
           # words[1]=0
           # words[2]=0
           # continue

        *axis=(cos(pitch)*cos(yaw),-cos(pitch)*sin(yaw),sin(pitch))*
        #print axis
        *
up=(sin(roll)*sin(yaw)+cos(roll)*sin(pitch)*cos(yaw),sin(roll)*cos(yaw)-cos(roll)*sin(pitch)*sin(yaw),-cos(roll)*cos(pitch))
*
       # print up
        platform.axis=axis
        platform.up=up
        platform.length=1.0
        platform.width=0.65
        plat_arrow.axis=axis
        plat_arrow.up=up
        plat_arrow.length=0.8
        p_line.axis=axis
        p_line.up=up
        cil_roll.axis=(0.2*cos(roll),0.2*sin(roll),0)
        cil_roll2.axis=(-0.2*cos(roll),-0.2*sin(roll),0)
        cil_pitch.axis=(0.2*cos(pitch),0.2*sin(pitch),0)
        cil_pitch2.axis=(-0.2*cos(pitch),-0.2*sin(pitch),0)
        arrow_course.axis=(0.2*sin(yaw),0.2*cos(yaw),0)
        L1.text = str(float(words[0]))
        L2.text = str(float(words[1]))
        L3.text = str(float(words[2]))
ser.close
f.close

===========================================================================================
here http://www.youtube.com/watch?v=WuHRCnpcsDQ   is the video of what the
above code does.

I would like to know the *axis **, **up* functionality ( how the object is
rotated meaning that, how the rotation matrix is programmed in these
functions to get the rotation of the object)

Thanks for reading...

Regards
Harinath