Glowscript Component Variables not functioning anymore.

[Kyle S.]

I do not know if there was an update or something similar these past few days, but for some reason, a program I was writing for a school program is no longer functioning. I have not been the only one having this problem. Several of my classmates encountered similar issues. Having changed nothing since yesterday, upon opening and running my program today the simulation no longer runs. Since the program itself runs, but not as it should and did a few days ago I have no idea as to how to resolve this issue or if there is a solution. What several classmates and I have determined to be the issue is that in the while loop, when declaring a component of a variable to be a new value with each run the program no longer does this. So when before something like, thisobject.pos.x=thisobject.pos.x+2dt, would create motion it no longer does. Here is the code I have at the moment as it was when it was last working, yesterday, Monday the 22nd. If anyone knows why this no longer works or how to fix it, please give your input.

GlowScript 2.4 VPython

  #Use these Variables to Run the program. 

    #suggested values of 0<x<90

angled=45

    #suggested values of 1<x<20

mass=80

    #suggested values of 20<x

velocity=20

    #Values must fall between 0<x<1

elasticity=.4

    #FrictionForce

forcef=0

#Do not Change anything below this point

alert('READ THIS. To launch a second orb, please restart the program. To launch press spacebar. For best results launch immediately. You have only around 15 seconds for your launch to proceed. Doubleclick SPACE to begin.')

scene.camera.pos=vec(0,0,0)

scene.camera.axis=vec(-.25,-.75,-1)

scene.width=1000

scene.height=500

scene.range=65

scene.autoscale=False

accelg=-9.8

angleb=angled*(pi/180)

vx=velocity*cos(angleb)

vy=velocity*sin(angleb)

cannonlengthx=5*cos(angleb)

cannonlengthy=5*sin(angleb)

t=0

def keyboard(event):

    if event.type='keydown':

        k=event.which

      #print(k)

        if k==32:

            bullet=sphere(pos=vec(-100+cannonlengthx,2+cannonlengthy,0), radius=0.9, color=color.white, make_trail=True,trail_type="points",

              interval=30, retain=80,texture="https://st.depositphotos.com/3113551/4586/v/950/depositphotos_45865131-stock-illustration-golf-ball-texture.jpg")

            bullet.v=vec(vx,vy,0)

            bulletsList.append(bullet)

            t=0

scene.bind('keydown', keyboard)

bulletsList=[]

scene.title = "Cannon Launch and Elasticity \n"

bore= cylinder(pos=vec(-100,2,1), axis=vec(5,0,0), radius=1, texture=textures.rough)

platform=box(pos=vec(0,0,0), size=vec(200,1,20), color=color.orange, texture=textures.wood_old)

platformgreen=box(pos=vec(0,0.1,0), size=vec(190,1,10), color=color.green, texture=textures.rough)

goal=cylinder(pos=vec(90,0,0), axis=vec(0,1,0))

goal=cylinder(pos=vec(90,0,0), axis=vec(0,1,0))

flag=cylinder(pos=vec(90,3,0), axis=vec(0,15,0), radius=0.5)

a = vertex( pos=vec(90,18,0) , color=color.red)

b = vertex( pos=vec(90,14,0) , color=color.red)

c = vertex( pos=vec(85,16,0) , color=color.red)

T = triangle( vs=[a,b,c] )

wheel= sphere(pos=vec(-100,2,1), radius=1.5, color=color.white, texture=textures.rough)

bore.rotate(angle=angleb,axis=vec(0,0,1),origin=wheel.pos, color=color.white)

dt=.01

ft=0

dft=0.01

velocityx=series(color=color.cyan, label='velocity vs. time')

#kineticenergy=series(color=color.green, label="kinetic energy vs. time")

while 1:

    rate(200)

    at=0

    ddt=1

    at=at+ddt

    for thisbullet in bulletsList:

        ke=.5*mass*thisbullet.v.y**2

        if thisbullet.pos.x<90:

            thisbullet.pos.x=thisbullet.pos.x+thisbullet.v.x*dt

            thisbullet.v.y=thisbullet.v.y+accelg*dt

        thisbullet.pos.y=thisbullet.pos.y+thisbullet.v.y*dt+(1/2)*accelg*dt**2

        if thisbullet.pos.x > 90:

            thisbullet.v=vec(0,0,0)

            accelg=0

            break

            del thisbullet

            thisbullet.visible=False

        elif thisbullet.pos.y>2.01:

            ft=0

        elif thisbullet.pos.y<2.01:

            thisbullet.v.y=-1*thisbullet.v.y

            thisbullet.v.y=(sqrt((2*(elasticity*ke))/mass))

            thisbullet.v.x=thisbullet.v.x-(forcef*ft/mass)

            ft=ft+dft

            

        elif thisbullet.pos.y<2.1 and thisbullet.pos.x>60:

            thisbullet.pos.y=2

            accelg=0

        while thisbullet.v.x<0:

            thisbullet.v=vec(0,0,0)

            accelg=0

        

        

            #thisbullet.visible=False

        #kineticenergy.plot(t,ke)

        if t<10:

            velocityx.plot(t,thisbullet.v.x)

        if at==1+ddt:

            print('Horizontal Velocity:',thisbullet.v.x)

    

    t=t+dt

    #elif thisbullet.pos.x >90:

            #break

        

    

    

[Bruce Sherwood]

Thanks very much for this report. I do not understand the problem. Your programs and other programs that change object.pos.x (or y or z) work correctly when running locally on my test computer, but when the software is uploaded to glowscript.org, it fails on all platforms (Windows, Mac, Linux).

In your specific case, a workaround is to use GlowScript 2.3 VPython, or to update object.pos rather than object.pos.x. Obviously though I have to deal with the existing problem.

[kyle...@gmail.com]

I'm relatively new to GlowScript and use it so I can run the program on things like Chromebooks. How would I go about utilizing the 2.3 version as compared to 2.4? I apologize for my ignorance on this matter, but I normally use desktop IDEs, and I decided to give Glowscript a try to run a physics simulation.

[Bruce Sherwood]

Sorry, I should have been more explicit. Just change the "2.4" in the first line of the program to "2.3".

The only feature that seems to be broken is changing object.pos.x, so another workaround is to modify object.pos instead of modifying object.pos.x.