updated some no_notebook demo programs

Demos_no_notebook/Color-RGB-HSV-from-terminal.py

@@ -0,0 +1,47 @@
+from vpython import *
+# This version uses VPython slider
+# See ButtonsSlidersMenus1 for a version that uses Jupyter slider
+
+scene.userzoom = False
+scene.userspin = False
+scene.width = 400
+scene.height = 200
+scene.range = 1
+scene.background = color.red
+box(pos=vector(10,0,0)) # Force creation of canvas; box is not seen because it is outside the canvas
+cancopy = 'You can Ctrl-C or Command-C copy these RGB and HSV values:\n'
+scene.title = cancopy
+scene.append_to_title("RGB = <1.000, 0.000, 0.000>, HSV = <0.000, 0.000, 0.000>")
+
+C = ['Red', 'Green', 'Blue', 'Hue', 'Saturation', 'Value']
+sliders = []
+
+def set_background(sl):
+    if sl.id < 3:
+        rgb = vector(sliders[0].value, sliders[1].value, sliders[2].value)
+        hsv = color.rgb_to_hsv(rgb)
+        sliders[3].value = int(1000*hsv.x)/1000# reset HSV slider positions; display 3 figures
+        sliders[4].value = int(1000*hsv.y)/1000
+        sliders[5].value = int(1000*hsv.z)/1000
+    else:
+        hsv = vector(sliders[3].value, sliders[4].value, sliders[5].value)
+        rgb = color.hsv_to_rgb(hsv)
+        sliders[0].value = int(1000*rgb.x)/1000 # reset RGB slider positions; display 3 figures
+        sliders[1].value = int(1000*rgb.y)/1000
+        sliders[2].value = int(1000*rgb.z)/1000
+    scene.background = rgb
+    # For readability, limit precision of display of quantities to 3 figures
+    f = "RGB = <{:1.3f}, {:1.3f}, {:1.3f}>, HSV = <{:1.3f}, {:1.3f}, {:1.3f}>"
+    scene.title = cancopy + f.format(rgb.x, rgb.y, rgb.z, hsv.x, hsv.y, hsv.z)
+
+scene.caption = '\n'
+for i in range(6): # Create the 3 RGB and 3 HSV sliders
+    sliders.append(slider(length=300, left=10, min=0, max=1, bind=set_background, id=i))
+    scene.append_to_caption('    '+C[i]+'\n\n') # Display slider name
+    if i == 2: scene.append_to_caption("\n\n") # Separate the RGB and HSV sliders
+sliders[0].value = 1 # make the background red
+sliders[4].value = sliders[5].value = 1
+
+
+while True:       # Needed when running from a terminal
+    rate(30)

Demos_no_notebook/DipoleElectricField-from-terminal.py

@@ -0,0 +1,65 @@
+from vpython import *
+
+scale = 4e-14/1e17
+ec = 1.6e-19  # electron charge
+kel = 9e9     # Coulomb constant
+scene.range = 2e-13
+
+charges = [ sphere( pos=vector(-1e-13,0,0), Q=ec,  color=color.red,  size=1.2e-14*vector(1,1,1) ),
+            sphere( pos=vector( 1e-13,0,0), Q=-ec, color=color.blue, size=1.2e-14*vector(1,1,1) )]
+
+s = "Click or drag to plot an electric field vector produced by the two charges.\n"
+s += "On a touch screen, tap, or press and hold, then drag.\n"
+s += "Arrows representing the field are bluer if low magnitude, redder if high."
+scene.caption = s
+
+def getfield(p):
+    f = vec(0,0,0)
+    for c in charges:
+        f = f + (p-c.pos) * kel * c.Q / mag(p-c.pos)**3
+    return f
+
+def mouse_to_field(a):
+    p = scene.mouse.pos
+    f = getfield(p)
+    m = mag(f)
+    red = max( 1-1e17/m, 0 )
+    blue = min(  1e17/m, 1 )
+    if red >= blue:
+        blue = blue/red
+        red = 1.0
+    else:
+        red = red/blue
+        blue = 1.0
+    a.pos = p
+    a.axis = scale*f
+    a.color = vector(red,0,blue)
+    a.visible = True
+
+drag = False
+a = None
+
+def down(ev):
+    global a, drag
+    a = arrow(shaftwidth=6e-15, visible=False)
+    mouse_to_field(a)
+    drag = True
+
+def move(ev):
+    global a, drag
+    if not drag: return
+    mouse_to_field(a)
+
+def up(ev):
+    global a, drag
+    mouse_to_field(a)
+    drag = False
+
+scene.bind("mousedown", down)
+
+scene.bind("mousemove", move)
+
+scene.bind("mouseup", up)
+
+while True:       # Needed when running from a terminal
+    rate(30)

Demos_no_notebook/MousePicking-from-terminal.py

@@ -0,0 +1,56 @@
+from vpython import *
+scene.width = scene.height = 500
+scene.background = color.gray(0.8)
+scene.range = 2.2
+scene.caption = "Click to pick an object and make it red."
+scene.append_to_caption("\nNote picking of individual curve segments.")
+box(pos=vector(-1,0,0), color=color.cyan, opacity=1)
+box(pos=vector(1,-1,0), color=color.green)
+arrow(pos=vector(-1,-1.3,0), color=color.orange)
+cone(pos=vector(2,0,0), axis=vector(0,1,-.3), color=color.blue, size=vector(2,1,1))
+sphere(pos=vector(-1.5,1.5,0), color=color.white, size=.4*vector(3,2,1))
+square = curve(color=color.yellow, radius=.05)
+square.append(vector(0,0,0))
+square.append(pos=vector(0,1,0), color=color.cyan, radius=.1)
+square.append(vector(1,1,0))
+square.append(pos=vector(1,0,0), radius=.1)
+square.append(vector(0.3,-.3,0))
+v0 = vertex(pos=vector(-.5,1.2,0), color=color.green)
+v1 = vertex(pos=vector(1,1.2,0), color=color.red)
+v2 = vertex(pos=vector(1,2,0), color=color.blue)
+v3 = vertex(pos=vector(-.5,2,0), color=color.yellow)
+quad(vs=[v0, v1, v2, v3])
+extrusion(path=[vector(-1.8,-1.3,0), vector(-1.4,-1.3,0)],
+            shape=shapes.circle(radius=.5, thickness=0.4), color=color.yellow)
+ring(pos=vector(-0.6,-1.3,0), size=vector(0.2,1,1), color=color.green)
+lasthit = None
+lastpick = None
+lastcolor = None
+
+def getevent(evt):
+    global lasthit, lastpick, lastcolor
+    if lasthit != None:
+        if lastpick != None: lasthit.modify(lastpick, color=lastcolor)
+        else: lasthit.color = vector(lastcolor)
+        lasthit = lastpick = None
+
+    hit = scene.mouse.pick
+    if hit != None:
+        lasthit = hit
+        lastpick = None
+        if isinstance(hit, curve):  # pick individual point of curve
+            lastpick = hit.segment
+            lastcolor = hit.point(lastpick)['color']
+            hit.modify(lastpick, color=color.red)
+        elif isinstance(hit, quad):
+            lasthit = hit.v0
+            lastcolor = vector(lasthit.color) # make a copy
+            lasthit.color = color.red
+        else:
+            lastcolor = vector(hit.color) # make a copy
+            hit.color = color.red
+
+scene.bind("mousedown", getevent)
+
+while True:       # Needed when running from a terminal
+    rate(30)

Demos_no_notebook/qt.py

@@ -1,4 +1,4 @@
 from vpython import *
-set_browser(type='pyqt')
+set_browser(type='pyqt5')
 b = box()
 scene.caption = "A box should appear in the window above"

vpython/no_notebook.py

@@ -52,7 +52,12 @@ def run(*args, **kwargs):
 # Check for Ctrl+C. SIGINT will also be sent by our code if WServer is closed.
 def signal_handler(signal, frame):
     #print("in signal handler, calling stop server")
-    stop_server()
+    try:
+        stop_server()
+    except (KeyboardInterrupt):
+        pass
+    except:
+        raise
 
 signal.signal(signal.SIGINT, signal_handler)