from visual import *
import povexport

print """Instructions: 
Change viewpoint by using ctrl-click or cmd-click and dragging.

To generate POV-Ray code of a particular view, click in the scene.
You may export multiple views.  Each file will be given a name
prefixed with a number which increments with each picture FOR
AN INSTANCE OF THE PROGRAM.
"""

######################################################
# B field
Bshaft=0.5
Bsize=-2
Bdirect=vector(0,0,Bsize)
inc1=vector(2.5,0,0)
inc2=vector(0,2.5,0)
######################################################

scene = display(background=color.white)
plane = box(pos=vector(0,0,0), length=2.5*mag(inc1), width=0.1, height=2.5*mag(inc1))
plane.color=color.green
plane.opacity=0.2


B00=arrow(pos=vector(0,0,-Bsize/2.0)+0.0*inc1+0.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)
B20=arrow(pos=vector(0,0,-Bsize/2.0)-1.0*inc1+0.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)
B30=arrow(pos=vector(0,0,-Bsize/2.0)+1.0*inc1+0.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)

B01=arrow(pos=vector(0,0,-Bsize/2.0)+0.0*inc1-1.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)
B21=arrow(pos=vector(0,0,-Bsize/2.0)-1.0*inc1-1.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)
B31=arrow(pos=vector(0,0,-Bsize/2.0)+1.0*inc1-1.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)

B03=arrow(pos=vector(0,0,-Bsize/2.0)+0.0*inc1+1.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)
B23=arrow(pos=vector(0,0,-Bsize/2.0)-1.0*inc1+1.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)
B33=arrow(pos=vector(0,0,-Bsize/2.0)+1.0*inc1+1.0*inc2, axis=Bdirect, shaft=Bshaft, color=color.blue)


# simple current loop
Ishaft=1.0
corner=vector(-1,-0.75,+.3)
axis1=vector(2,0,-0.6)
axis2=vector(0,1.5,0)
axis3=vector(-2,0,0.6)
axis4=vector(0,-1.5,0)

current=0.25
Iarrow1=arrow(pos=corner, axis=axis1, shaft=Ishaft)
Iarrow2=arrow(pos=Iarrow1.pos+Iarrow1.axis, axis=axis2, shaft=Ishaft)
Iarrow3=arrow(pos=Iarrow2.pos+Iarrow2.axis, axis=axis3, shaft=Ishaft)
Iarrow4=arrow(pos=Iarrow3.pos+Iarrow3.axis, axis=axis4, shaft=Ishaft)

force1=current*cross(axis1,Bdirect)
force2=current*cross(axis2,Bdirect)
force3=current*cross(axis3,Bdirect)
force4=current*cross(axis4,Bdirect)

fshaft=0.75
farrow1=arrow(pos=Iarrow1.pos+axis1/2, axis=force1, color=color.red)
farrow2=arrow(pos=Iarrow2.pos+axis2/2, axis=force2, color=color.red)
farrow3=arrow(pos=Iarrow3.pos+axis3/2, axis=force3, color=color.red)
farrow4=arrow(pos=Iarrow4.pos+axis4/2, axis=force4, color=color.red)

tarrow=arrow(pos=vector(0,0,0), axis=cross(axis1,force2)*3, color=color.yellow)

import time
counter=0

while 1:
	scene.mouse.getclick()  ## position camera somewhere, then click
	povexport.export(filename="%1.0_loopTorque.pov" %counter, display=scene)
	print "Export finished"
	counter=counter+1