Support for python seems to be limited in the offline package
Closed this issue · 6 comments
I had developed the bouncing ball in a box demo mentioned in vpython intro(the pdf doc) in anaconda.
For better coding style, I used a class definition to add multiple particle instances, it worked OK in anaconda, but failed to create any class instance without any warning/error when imported in the offline package.
Please provide a brief example that fails, as classes are supported in GlowScript VPython. (I'll also comment that "sphere" IS a class, so s1 = sphere() and s2 = sphere() are two instances of the class "sphere".)
Codes which failed in the offline package but successed in anaconda
from vpython import *
wallL = box(pos=vector(-6,0,0),
size=vector(0.2,12,12),
color=color.green,
opacity = 0.5)
wallR = box(pos=vector(6,0,0),
size=vector(0.2,12,12),
color=color.green,
opacity = 0.5)
wallU = box(pos=vector(0,6,0),
size=vector(12,0.2,12),
color=color.green,
opacity = 0.5)
wallD = box(pos=vector(0,-6,0),
size=vector(12,0.2,12),
color=color.green,
opacity = 0.5)
wallB = box(pos=vector(0,0,-6),
size=vector(12,12,0.2),
color=color.green,
opacity = 0.5)
wallF = vector(0,0,6)
class particle(object):
def __init__(self, pos, velocity, color_param, make_trail = True, vscale = 0.1):
self.time = 0.0
self.pos = pos
self.velocity = velocity
self.color = color_param
self.vscale = vscale
self.entity = sphere(pos=self.pos, radius=0.5, color=self.color, make_trail=make_trail)
self.varr = arrow(pos=self.pos, axis=self.vscale*self.velocity, color=color.yellow)
def propagate(self, deltat):
if self.pos.x > wallR.pos.x-wallR.size.x*0.5 or self.pos.x < wallL.pos.x+wallL.size.x*0.5:
self.velocity.x = -self.velocity.x
if self.pos.y > wallU.pos.y-wallU.size.y*0.5 or self.pos.y < wallD.pos.y+wallD.size.y*0.5:
self.velocity.y = -self.velocity.y
if self.pos.z > wallF.z-wallB.size.z*0.5 or self.pos.z < wallB.pos.z+wallB.size.z*0.5:
self.velocity.z = -self.velocity.z
self.varr.pos = self.entity.pos
self.varr.axis = self.vscale*self.velocity
self.entity.pos = self.entity.pos + self.velocity*deltat
self.pos = self.entity.pos
ball_001 = particle(vector(0,0,0),vector(25,5,10),color.red)
ball_002 = particle(vector(0,0,0),vector(10,15,5),color.cyan)
deltat = 0.005
t = 0
scene.autoscale = False
while t < 100:
rate(100)
ball_001.propagate(deltat)
ball_002.propagate(deltat)
t = t + deltat
Codes which are OK. Besides, import vpython as vp is not supported, but I prefer this style to avoid naming conflicts with existing codes.
from vpython import *
wallL = box(pos=vector(-6,0,0),
size=vector(0.2,12,12),
color=color.green,
opacity = 0.5)
wallR = box(pos=vector(6,0,0),
size=vector(0.2,12,12),
color=color.green,
opacity = 0.5)
wallU = box(pos=vector(0,6,0),
size=vector(12,0.2,12),
color=color.green,
opacity = 0.5)
wallD = box(pos=vector(0,-6,0),
size=vector(12,0.2,12),
color=color.green,
opacity = 0.5)
wallB = box(pos=vector(0,0,-6),
size=vector(12,12,0.2),
color=color.green,
opacity = 0.5)
wallF = vector(0,0,6)
vscale = 0.1
velocity = vector(25,5,10)
entity = sphere(pos=vector(0,0,0), radius=0.5, color=color.red, make_trail=True)
varr = arrow(pos=entity.pos, axis=vscale*velocity, color=color.yellow)
deltat = 0.005
t = 0
scene.autoscale = False
while t < 100:
rate(100)
if entity.pos.x > wallR.pos.x-wallR.size.x*0.5 or entity.pos.x < wallL.pos.x+wallL.size.x*0.5:
velocity.x = -velocity.x
if entity.pos.y > wallU.pos.y-wallU.size.y*0.5 or entity.pos.y < wallD.pos.y+wallD.size.y*0.5:
velocity.y = -velocity.y
if entity.pos.z > wallF.z-wallB.size.z*0.5 or entity.pos.z < wallB.pos.z+wallB.size.z*0.5:
velocity.z = -velocity.z
varr.pos = entity.pos
varr.axis = vscale*velocity
entity.pos = entity.pos + velocity*deltat
t = t + deltat
Just write "class particle():" or "class particle:"; and your program works. I think the need to inherit from object is a syntax that was needed in Python 2 but is irrelevant in Python 3, which is what RapydScript-NG is based on
Thanks for pointing out the failure of "import vpython as vp", which does work at glowscript.org. I think I see what needs to be fixed.
Bruce
Thanks a lot for testing those codes. More over, is there any plan to port the offine package to Python 3?
I'm not sure what you mean. As I said, the RapydScript-NG Python-to-JavaScript transpiler treats your code as being for Python 3. As for an offline package for true Python 3 (that is, installed Python 3 with access to all Python modules), that already exists; it's called VPython 7. See vpython.org for details.
I've updated the offline package to handle import statements correctly. Thanks again for pointing out this need.
Bruce