VPython 轨道运动窃听

Question

我尝试过可视化太阳系的轨道，然后使用 vpython 库包含一个系外行星轨道。

它运行良好，但在程序开始时，有时轨道会跳过它们的圆周运动，而是跳到轨道中的不同位置，然后继续。行星轨迹留下锋利的边缘并穿过其他轨道。

我已上传问题的屏幕截图以显示 -

我在下面附上了我的代码，如果可能的话，有人可以帮我解决这个问题吗？非常感谢所有帮助，谢谢。

（为代码道歉，我正在学习，我正在努力改进它）

    ##  Constants
# Radii:
starrad = 696.34e6
exoplanetrad = 3.8e6
mercuryrad = 2.44e6
venusrad = 6.05e6
earthrad = 6.38e6
marsrad = 3.4e6

# Position:
exoplanetpos = vector((8e9+starrad), 0, 0)
mercurypos = vector((5.79e9+starrad), 0, 0)
venuspos = vector((1.082e10+starrad), 0, 0)
earthpos = vector((1.496e10+starrad), 0, 0)
marspos = vector((2.279e10+starrad), 0, 0)

# Orbital Periods (Days):
exoplanetperiod = 170
mercuryperiod = 88
venusperiod = 224.7
earthperiod = 365.2
marsperiod = 687

# CHZ Attributes
chz_inner = ((0.75*mag(earthpos)) + starrad)
chz_outer = ((1.7*mag(earthpos)) + starrad)
chz_thickness = (0.009*mag(earthpos))

# Time
t = 0
deltat = 0.1

# Scene and Lights
#scene.autoscale = 0     # Removes autoscaling for better visuals
star_light = local_light(pos=vector(0,0,0), color=color.white, visible = True)


    ##  Objects
star=sphere(color=color.orange,pos=vec(0,0,0),radius=starrad, emissive=True, texture = "http://i.imgur.com/yoEzbtg.jpg")
exoplanet=sphere(color=color.cyan,pos=exoplanetpos,radius=exoplanetrad, shininess=10, make_trail=True)
mercury=sphere(color=color.gray(0.75),pos=mercurypos,radius=mercuryrad, shininess=10, make_trail=True, opacity = 0.5)
venus=sphere(color=color.gray(0.75),pos=venuspos,radius=venusrad, shininess=10, make_trail=True, opacity = 0.5)
earth=sphere(color=color.gray(0.75),pos=earthpos,radius=earthrad, shininess=10, make_trail=True, opacity = 0.5)
mars=sphere(color=color.gray(0.75),pos=marspos,radius=marsrad, shininess=10, make_trail=True, opacity = 0.5)
ring1 = ring(pos= vec(0,0,0), axis = vec(0,1,0), radius = chz_inner, thickness = chz_thickness, color = color.green, opacity = 0.75)
ring2 = ring(pos= vec(0,0,0), axis = vec(0,1,0), radius = chz_outer, thickness = chz_thickness, color = color.red, opacity = 0.75)


    ##  Labels
star_label = label(pos=star.pos,
    text='Star', xoffset=10,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')

exoplanet_label = label(pos=exoplanet.pos,
    text='Exoplanet', xoffset=10,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')

mercury_label = label(pos=mercury.pos,
    text='Mercury', xoffset=10,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')

venus_label = label(pos=venus.pos,
    text='Venus', xoffset=10,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')

earth_label = label(pos=earth.pos,
    text='Earth', xoffset=10,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')

ring_label = label(pos=(ring1.pos+vector(0, 0, ring1.radius)),
    text='CHZ Inner', xoffset=2,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')

ring_label2 = label(pos=(ring2.pos+vector(0, 0, ring2.radius)),
    text='CHZ Outer', xoffset=2,
    line = False, yoffset=10, height=12, 
    border=3, font='sans')


    ##  Graphs
gd = graph(width=635, height=600, xtitle='Time', ytitle='Position',
           foreground=color.gray(0.5), background=color.white,
           xmax=20, xmin=0, ymax=6e10, ymin=-6e10)
g1 = gcurve(color=color.red)
g2 = gcurve(color=color.cyan) # a graphics curve


while True:
  rate(100)
  t = t + deltat
  star.rotate(angle=(2*3.14159/365), axis=vector(0,1,0), origin=vector(0,0,0))
  exoplanet.rotate(angle=(2*3.14159/exoplanetperiod), axis=vector(0,1,0), origin=vector(0,0,0))
  mercury.rotate(angle=(2*3.14159/mercuryperiod), axis=vector(0,1,0), origin=vector(0,0,0))
  venus.rotate(angle=(2*3.14159/venusperiod), axis=vector(0,1,0), origin=vector(0,0,0))
  earth.rotate(angle=(2*3.14159/earthperiod), axis=vector(0,1,0), origin=vector(0,0,0))
  mars.rotate(angle=(2*3.14159/marsperiod), axis=vector(0,1,0), origin=vector(0,0,0))
  g1.plot((t, exoplanet.pos.z))
  g2.plot((t, exoplanet.pos.x))

Answer 1

这很微妙。我假设您正在使用安装了 Python 的 vpython 模块，因为我没有看到 GlowScript VPython 的问题。问题是利率声明。考虑到大量的设置，循环开始时的 rate(100) 试图赶上并以高于每秒 100 的速率运行循环。仅在每次显示新图像时才会在曲线上添加一个点来表示轨迹，其效果是您可以获得相距较远的曲线的增量。改善这种情况的两种方法：1）在循环之前放置“sleep（1）”，这将重新校准速率函数，2）在最后一个轨道关闭后退出循环。另一种选择是不使用 make_trail 而是设置曲线并在移动行星时向曲线添加一个点，而不是依赖于仅在生成新显示时添加的点。