/usr/lib/python2.7/dist-packages/pyqtgraph/examples/relativity/relativity.py is in python-pyqtgraph 0.9.10-5.
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from pyqtgraph.Qt import QtGui, QtCore
from pyqtgraph.parametertree import Parameter, ParameterTree
from pyqtgraph.parametertree import types as pTypes
import pyqtgraph.configfile
import numpy as np
import user
import collections
import sys, os
class RelativityGUI(QtGui.QWidget):
def __init__(self):
QtGui.QWidget.__init__(self)
self.animations = []
self.animTimer = QtCore.QTimer()
self.animTimer.timeout.connect(self.stepAnimation)
self.animTime = 0
self.animDt = .016
self.lastAnimTime = 0
self.setupGUI()
self.objectGroup = ObjectGroupParam()
self.params = Parameter.create(name='params', type='group', children=[
dict(name='Load Preset..', type='list', values=[]),
#dict(name='Unit System', type='list', values=['', 'MKS']),
dict(name='Duration', type='float', value=10.0, step=0.1, limits=[0.1, None]),
dict(name='Reference Frame', type='list', values=[]),
dict(name='Animate', type='bool', value=True),
dict(name='Animation Speed', type='float', value=1.0, dec=True, step=0.1, limits=[0.0001, None]),
dict(name='Recalculate Worldlines', type='action'),
dict(name='Save', type='action'),
dict(name='Load', type='action'),
self.objectGroup,
])
self.tree.setParameters(self.params, showTop=False)
self.params.param('Recalculate Worldlines').sigActivated.connect(self.recalculate)
self.params.param('Save').sigActivated.connect(self.save)
self.params.param('Load').sigActivated.connect(self.load)
self.params.param('Load Preset..').sigValueChanged.connect(self.loadPreset)
self.params.sigTreeStateChanged.connect(self.treeChanged)
## read list of preset configs
presetDir = os.path.join(os.path.abspath(os.path.dirname(sys.argv[0])), 'presets')
if os.path.exists(presetDir):
presets = [os.path.splitext(p)[0] for p in os.listdir(presetDir)]
self.params.param('Load Preset..').setLimits(['']+presets)
def setupGUI(self):
self.layout = QtGui.QVBoxLayout()
self.layout.setContentsMargins(0,0,0,0)
self.setLayout(self.layout)
self.splitter = QtGui.QSplitter()
self.splitter.setOrientation(QtCore.Qt.Horizontal)
self.layout.addWidget(self.splitter)
self.tree = ParameterTree(showHeader=False)
self.splitter.addWidget(self.tree)
self.splitter2 = QtGui.QSplitter()
self.splitter2.setOrientation(QtCore.Qt.Vertical)
self.splitter.addWidget(self.splitter2)
self.worldlinePlots = pg.GraphicsLayoutWidget()
self.splitter2.addWidget(self.worldlinePlots)
self.animationPlots = pg.GraphicsLayoutWidget()
self.splitter2.addWidget(self.animationPlots)
self.splitter2.setSizes([int(self.height()*0.8), int(self.height()*0.2)])
self.inertWorldlinePlot = self.worldlinePlots.addPlot()
self.refWorldlinePlot = self.worldlinePlots.addPlot()
self.inertAnimationPlot = self.animationPlots.addPlot()
self.inertAnimationPlot.setAspectLocked(1)
self.refAnimationPlot = self.animationPlots.addPlot()
self.refAnimationPlot.setAspectLocked(1)
self.inertAnimationPlot.setXLink(self.inertWorldlinePlot)
self.refAnimationPlot.setXLink(self.refWorldlinePlot)
def recalculate(self):
## build 2 sets of clocks
clocks1 = collections.OrderedDict()
clocks2 = collections.OrderedDict()
for cl in self.params.param('Objects'):
clocks1.update(cl.buildClocks())
clocks2.update(cl.buildClocks())
## Inertial simulation
dt = self.animDt * self.params['Animation Speed']
sim1 = Simulation(clocks1, ref=None, duration=self.params['Duration'], dt=dt)
sim1.run()
sim1.plot(self.inertWorldlinePlot)
self.inertWorldlinePlot.autoRange(padding=0.1)
## reference simulation
ref = self.params['Reference Frame']
dur = clocks1[ref].refData['pt'][-1] ## decide how long to run the reference simulation
sim2 = Simulation(clocks2, ref=clocks2[ref], duration=dur, dt=dt)
sim2.run()
sim2.plot(self.refWorldlinePlot)
self.refWorldlinePlot.autoRange(padding=0.1)
## create animations
self.refAnimationPlot.clear()
self.inertAnimationPlot.clear()
self.animTime = 0
self.animations = [Animation(sim1), Animation(sim2)]
self.inertAnimationPlot.addItem(self.animations[0])
self.refAnimationPlot.addItem(self.animations[1])
## create lines representing all that is visible to a particular reference
#self.inertSpaceline = Spaceline(sim1, ref)
#self.refSpaceline = Spaceline(sim2)
self.inertWorldlinePlot.addItem(self.animations[0].items[ref].spaceline())
self.refWorldlinePlot.addItem(self.animations[1].items[ref].spaceline())
def setAnimation(self, a):
if a:
self.lastAnimTime = pg.ptime.time()
self.animTimer.start(self.animDt*1000)
else:
self.animTimer.stop()
def stepAnimation(self):
now = pg.ptime.time()
dt = (now-self.lastAnimTime) * self.params['Animation Speed']
self.lastAnimTime = now
self.animTime += dt
if self.animTime > self.params['Duration']:
self.animTime = 0
for a in self.animations:
a.restart()
for a in self.animations:
a.stepTo(self.animTime)
def treeChanged(self, *args):
clocks = []
for c in self.params.param('Objects'):
clocks.extend(c.clockNames())
#for param, change, data in args[1]:
#if change == 'childAdded':
self.params.param('Reference Frame').setLimits(clocks)
self.setAnimation(self.params['Animate'])
def save(self):
fn = str(pg.QtGui.QFileDialog.getSaveFileName(self, "Save State..", "untitled.cfg", "Config Files (*.cfg)"))
if fn == '':
return
state = self.params.saveState()
pg.configfile.writeConfigFile(state, fn)
def load(self):
fn = str(pg.QtGui.QFileDialog.getOpenFileName(self, "Save State..", "", "Config Files (*.cfg)"))
if fn == '':
return
state = pg.configfile.readConfigFile(fn)
self.loadState(state)
def loadPreset(self, param, preset):
if preset == '':
return
path = os.path.abspath(os.path.dirname(__file__))
fn = os.path.join(path, 'presets', preset+".cfg")
state = pg.configfile.readConfigFile(fn)
self.loadState(state)
def loadState(self, state):
if 'Load Preset..' in state['children']:
del state['children']['Load Preset..']['limits']
del state['children']['Load Preset..']['value']
self.params.param('Objects').clearChildren()
self.params.restoreState(state, removeChildren=False)
self.recalculate()
class ObjectGroupParam(pTypes.GroupParameter):
def __init__(self):
pTypes.GroupParameter.__init__(self, name="Objects", addText="Add New..", addList=['Clock', 'Grid'])
def addNew(self, typ):
if typ == 'Clock':
self.addChild(ClockParam())
elif typ == 'Grid':
self.addChild(GridParam())
class ClockParam(pTypes.GroupParameter):
def __init__(self, **kwds):
defs = dict(name="Clock", autoIncrementName=True, renamable=True, removable=True, children=[
dict(name='Initial Position', type='float', value=0.0, step=0.1),
#dict(name='V0', type='float', value=0.0, step=0.1),
AccelerationGroup(),
dict(name='Rest Mass', type='float', value=1.0, step=0.1, limits=[1e-9, None]),
dict(name='Color', type='color', value=(100,100,150)),
dict(name='Size', type='float', value=0.5),
dict(name='Vertical Position', type='float', value=0.0, step=0.1),
])
#defs.update(kwds)
pTypes.GroupParameter.__init__(self, **defs)
self.restoreState(kwds, removeChildren=False)
def buildClocks(self):
x0 = self['Initial Position']
y0 = self['Vertical Position']
color = self['Color']
m = self['Rest Mass']
size = self['Size']
prog = self.param('Acceleration').generate()
c = Clock(x0=x0, m0=m, y0=y0, color=color, prog=prog, size=size)
return {self.name(): c}
def clockNames(self):
return [self.name()]
pTypes.registerParameterType('Clock', ClockParam)
class GridParam(pTypes.GroupParameter):
def __init__(self, **kwds):
defs = dict(name="Grid", autoIncrementName=True, renamable=True, removable=True, children=[
dict(name='Number of Clocks', type='int', value=5, limits=[1, None]),
dict(name='Spacing', type='float', value=1.0, step=0.1),
ClockParam(name='ClockTemplate'),
])
#defs.update(kwds)
pTypes.GroupParameter.__init__(self, **defs)
self.restoreState(kwds, removeChildren=False)
def buildClocks(self):
clocks = {}
template = self.param('ClockTemplate')
spacing = self['Spacing']
for i in range(self['Number of Clocks']):
c = template.buildClocks().values()[0]
c.x0 += i * spacing
clocks[self.name() + '%02d' % i] = c
return clocks
def clockNames(self):
return [self.name() + '%02d' % i for i in range(self['Number of Clocks'])]
pTypes.registerParameterType('Grid', GridParam)
class AccelerationGroup(pTypes.GroupParameter):
def __init__(self, **kwds):
defs = dict(name="Acceleration", addText="Add Command..")
pTypes.GroupParameter.__init__(self, **defs)
self.restoreState(kwds, removeChildren=False)
def addNew(self):
nextTime = 0.0
if self.hasChildren():
nextTime = self.children()[-1]['Proper Time'] + 1
self.addChild(Parameter.create(name='Command', autoIncrementName=True, type=None, renamable=True, removable=True, children=[
dict(name='Proper Time', type='float', value=nextTime),
dict(name='Acceleration', type='float', value=0.0, step=0.1),
]))
def generate(self):
prog = []
for cmd in self:
prog.append((cmd['Proper Time'], cmd['Acceleration']))
return prog
pTypes.registerParameterType('AccelerationGroup', AccelerationGroup)
class Clock(object):
nClocks = 0
def __init__(self, x0=0.0, y0=0.0, m0=1.0, v0=0.0, t0=0.0, color=None, prog=None, size=0.5):
Clock.nClocks += 1
self.pen = pg.mkPen(color)
self.brush = pg.mkBrush(color)
self.y0 = y0
self.x0 = x0
self.v0 = v0
self.m0 = m0
self.t0 = t0
self.prog = prog
self.size = size
def init(self, nPts):
## Keep records of object from inertial frame as well as reference frame
self.inertData = np.empty(nPts, dtype=[('x', float), ('t', float), ('v', float), ('pt', float), ('m', float), ('f', float)])
self.refData = np.empty(nPts, dtype=[('x', float), ('t', float), ('v', float), ('pt', float), ('m', float), ('f', float)])
## Inertial frame variables
self.x = self.x0
self.v = self.v0
self.m = self.m0
self.t = 0.0 ## reference clock always starts at 0
self.pt = self.t0 ## proper time starts at t0
## reference frame variables
self.refx = None
self.refv = None
self.refm = None
self.reft = None
self.recordFrame(0)
def recordFrame(self, i):
f = self.force()
self.inertData[i] = (self.x, self.t, self.v, self.pt, self.m, f)
self.refData[i] = (self.refx, self.reft, self.refv, self.pt, self.refm, f)
def force(self, t=None):
if len(self.prog) == 0:
return 0.0
if t is None:
t = self.pt
ret = 0.0
for t1,f in self.prog:
if t >= t1:
ret = f
return ret
def acceleration(self, t=None):
return self.force(t) / self.m0
def accelLimits(self):
## return the proper time values which bound the current acceleration command
if len(self.prog) == 0:
return -np.inf, np.inf
t = self.pt
ind = -1
for i, v in enumerate(self.prog):
t1,f = v
if t >= t1:
ind = i
if ind == -1:
return -np.inf, self.prog[0][0]
elif ind == len(self.prog)-1:
return self.prog[-1][0], np.inf
else:
return self.prog[ind][0], self.prog[ind+1][0]
def getCurve(self, ref=True):
if ref is False:
data = self.inertData
else:
data = self.refData[1:]
x = data['x']
y = data['t']
curve = pg.PlotCurveItem(x=x, y=y, pen=self.pen)
#x = self.data['x'] - ref.data['x']
#y = self.data['t']
step = 1.0
#mod = self.data['pt'] % step
#inds = np.argwhere(abs(mod[1:] - mod[:-1]) > step*0.9)
inds = [0]
pt = data['pt']
for i in range(1,len(pt)):
diff = pt[i] - pt[inds[-1]]
if abs(diff) >= step:
inds.append(i)
inds = np.array(inds)
#t = self.data['t'][inds]
#x = self.data['x'][inds]
pts = []
for i in inds:
x = data['x'][i]
y = data['t'][i]
if i+1 < len(data):
dpt = data['pt'][i+1]-data['pt'][i]
dt = data['t'][i+1]-data['t'][i]
else:
dpt = 1
if dpt > 0:
c = pg.mkBrush((0,0,0))
else:
c = pg.mkBrush((200,200,200))
pts.append({'pos': (x, y), 'brush': c})
points = pg.ScatterPlotItem(pts, pen=self.pen, size=7)
return curve, points
class Simulation:
def __init__(self, clocks, ref, duration, dt):
self.clocks = clocks
self.ref = ref
self.duration = duration
self.dt = dt
@staticmethod
def hypTStep(dt, v0, x0, tau0, g):
## Hyperbolic step.
## If an object has proper acceleration g and starts at position x0 with speed v0 and proper time tau0
## as seen from an inertial frame, then return the new v, x, tau after time dt has elapsed.
if g == 0:
return v0, x0 + v0*dt, tau0 + dt * (1. - v0**2)**0.5
v02 = v0**2
g2 = g**2
tinit = v0 / (g * (1 - v02)**0.5)
B = (1 + (g2 * (dt+tinit)**2))**0.5
v1 = g * (dt+tinit) / B
dtau = (np.arcsinh(g * (dt+tinit)) - np.arcsinh(g * tinit)) / g
tau1 = tau0 + dtau
x1 = x0 + (1.0 / g) * ( B - 1. / (1.-v02)**0.5 )
return v1, x1, tau1
@staticmethod
def tStep(dt, v0, x0, tau0, g):
## Linear step.
## Probably not as accurate as hyperbolic step, but certainly much faster.
gamma = (1. - v0**2)**-0.5
dtau = dt / gamma
return v0 + dtau * g, x0 + v0*dt, tau0 + dtau
@staticmethod
def tauStep(dtau, v0, x0, t0, g):
## linear step in proper time of clock.
## If an object has proper acceleration g and starts at position x0 with speed v0 at time t0
## as seen from an inertial frame, then return the new v, x, t after proper time dtau has elapsed.
## Compute how much t will change given a proper-time step of dtau
gamma = (1. - v0**2)**-0.5
if g == 0:
dt = dtau * gamma
else:
v0g = v0 * gamma
dt = (np.sinh(dtau * g + np.arcsinh(v0g)) - v0g) / g
#return v0 + dtau * g, x0 + v0*dt, t0 + dt
v1, x1, t1 = Simulation.hypTStep(dt, v0, x0, t0, g)
return v1, x1, t0+dt
@staticmethod
def hypIntersect(x0r, t0r, vr, x0, t0, v0, g):
## given a reference clock (seen from inertial frame) has rx, rt, and rv,
## and another clock starts at x0, t0, and v0, with acceleration g,
## compute the intersection time of the object clock's hyperbolic path with
## the reference plane.
## I'm sure we can simplify this...
if g == 0: ## no acceleration, path is linear (and hyperbola is undefined)
#(-t0r + t0 v0 vr - vr x0 + vr x0r)/(-1 + v0 vr)
t = (-t0r + t0 *v0 *vr - vr *x0 + vr *x0r)/(-1 + v0 *vr)
return t
gamma = (1.0-v0**2)**-0.5
sel = (1 if g>0 else 0) + (1 if vr<0 else 0)
sel = sel%2
if sel == 0:
#(1/(g^2 (-1 + vr^2)))(-g^2 t0r + g gamma vr + g^2 t0 vr^2 -
#g gamma v0 vr^2 - g^2 vr x0 +
#g^2 vr x0r + \[Sqrt](g^2 vr^2 (1 + gamma^2 (v0 - vr)^2 - vr^2 +
#2 g gamma (v0 - vr) (-t0 + t0r + vr (x0 - x0r)) +
#g^2 (t0 - t0r + vr (-x0 + x0r))^2)))
t = (1./(g**2 *(-1. + vr**2)))*(-g**2 *t0r + g *gamma *vr + g**2 *t0 *vr**2 - g *gamma *v0 *vr**2 - g**2 *vr *x0 + g**2 *vr *x0r + np.sqrt(g**2 *vr**2 *(1. + gamma**2 *(v0 - vr)**2 - vr**2 + 2 *g *gamma *(v0 - vr)* (-t0 + t0r + vr *(x0 - x0r)) + g**2 *(t0 - t0r + vr* (-x0 + x0r))**2)))
else:
#-(1/(g^2 (-1 + vr^2)))(g^2 t0r - g gamma vr - g^2 t0 vr^2 +
#g gamma v0 vr^2 + g^2 vr x0 -
#g^2 vr x0r + \[Sqrt](g^2 vr^2 (1 + gamma^2 (v0 - vr)^2 - vr^2 +
#2 g gamma (v0 - vr) (-t0 + t0r + vr (x0 - x0r)) +
#g^2 (t0 - t0r + vr (-x0 + x0r))^2)))
t = -(1./(g**2 *(-1. + vr**2)))*(g**2 *t0r - g *gamma* vr - g**2 *t0 *vr**2 + g *gamma *v0 *vr**2 + g**2* vr* x0 - g**2 *vr *x0r + np.sqrt(g**2* vr**2 *(1. + gamma**2 *(v0 - vr)**2 - vr**2 + 2 *g *gamma *(v0 - vr) *(-t0 + t0r + vr *(x0 - x0r)) + g**2 *(t0 - t0r + vr *(-x0 + x0r))**2)))
return t
def run(self):
nPts = int(self.duration/self.dt)+1
for cl in self.clocks.itervalues():
cl.init(nPts)
if self.ref is None:
self.runInertial(nPts)
else:
self.runReference(nPts)
def runInertial(self, nPts):
clocks = self.clocks
dt = self.dt
tVals = np.linspace(0, dt*(nPts-1), nPts)
for cl in self.clocks.itervalues():
for i in xrange(1,nPts):
nextT = tVals[i]
while True:
tau1, tau2 = cl.accelLimits()
x = cl.x
v = cl.v
tau = cl.pt
g = cl.acceleration()
v1, x1, tau1 = self.hypTStep(dt, v, x, tau, g)
if tau1 > tau2:
dtau = tau2-tau
cl.v, cl.x, cl.t = self.tauStep(dtau, v, x, cl.t, g)
cl.pt = tau2
else:
cl.v, cl.x, cl.pt = v1, x1, tau1
cl.t += dt
if cl.t >= nextT:
cl.refx = cl.x
cl.refv = cl.v
cl.reft = cl.t
cl.recordFrame(i)
break
def runReference(self, nPts):
clocks = self.clocks
ref = self.ref
dt = self.dt
dur = self.duration
## make sure reference clock is not present in the list of clocks--this will be handled separately.
clocks = clocks.copy()
for k,v in clocks.iteritems():
if v is ref:
del clocks[k]
break
ref.refx = 0
ref.refv = 0
ref.refm = ref.m0
## These are the set of proper times (in the reference frame) that will be simulated
ptVals = np.linspace(ref.pt, ref.pt + dt*(nPts-1), nPts)
for i in xrange(1,nPts):
## step reference clock ahead one time step in its proper time
nextPt = ptVals[i] ## this is where (when) we want to end up
while True:
tau1, tau2 = ref.accelLimits()
dtau = min(nextPt-ref.pt, tau2-ref.pt) ## do not step past the next command boundary
g = ref.acceleration()
v, x, t = Simulation.tauStep(dtau, ref.v, ref.x, ref.t, g)
ref.pt += dtau
ref.v = v
ref.x = x
ref.t = t
ref.reft = ref.pt
if ref.pt >= nextPt:
break
#else:
#print "Stepped to", tau2, "instead of", nextPt
ref.recordFrame(i)
## determine plane visible to reference clock
## this plane goes through the point ref.x, ref.t and has slope = ref.v
## update all other clocks
for cl in clocks.itervalues():
while True:
g = cl.acceleration()
tau1, tau2 = cl.accelLimits()
##Given current position / speed of clock, determine where it will intersect reference plane
#t1 = (ref.v * (cl.x - cl.v * cl.t) + (ref.t - ref.v * ref.x)) / (1. - cl.v)
t1 = Simulation.hypIntersect(ref.x, ref.t, ref.v, cl.x, cl.t, cl.v, g)
dt1 = t1 - cl.t
## advance clock by correct time step
v, x, tau = Simulation.hypTStep(dt1, cl.v, cl.x, cl.pt, g)
## check to see whether we have gone past an acceleration command boundary.
## if so, we must instead advance the clock to the boundary and start again
if tau < tau1:
dtau = tau1 - cl.pt
cl.v, cl.x, cl.t = Simulation.tauStep(dtau, cl.v, cl.x, cl.t, g)
cl.pt = tau1-0.000001
continue
if tau > tau2:
dtau = tau2 - cl.pt
cl.v, cl.x, cl.t = Simulation.tauStep(dtau, cl.v, cl.x, cl.t, g)
cl.pt = tau2
continue
## Otherwise, record the new values and exit the loop
cl.v = v
cl.x = x
cl.pt = tau
cl.t = t1
cl.m = None
break
## transform position into reference frame
x = cl.x - ref.x
t = cl.t - ref.t
gamma = (1.0 - ref.v**2) ** -0.5
vg = -ref.v * gamma
cl.refx = gamma * (x - ref.v * t)
cl.reft = ref.pt # + gamma * (t - ref.v * x) # this term belongs here, but it should always be equal to 0.
cl.refv = (cl.v - ref.v) / (1.0 - cl.v * ref.v)
cl.refm = None
cl.recordFrame(i)
t += dt
def plot(self, plot):
plot.clear()
for cl in self.clocks.itervalues():
c, p = cl.getCurve()
plot.addItem(c)
plot.addItem(p)
class Animation(pg.ItemGroup):
def __init__(self, sim):
pg.ItemGroup.__init__(self)
self.sim = sim
self.clocks = sim.clocks
self.items = {}
for name, cl in self.clocks.items():
item = ClockItem(cl)
self.addItem(item)
self.items[name] = item
#self.timer = timer
#self.timer.timeout.connect(self.step)
#def run(self, run):
#if not run:
#self.timer.stop()
#else:
#self.timer.start(self.dt)
def restart(self):
for cl in self.items.values():
cl.reset()
def stepTo(self, t):
for i in self.items.values():
i.stepTo(t)
class ClockItem(pg.ItemGroup):
def __init__(self, clock):
pg.ItemGroup.__init__(self)
self.size = clock.size
self.item = QtGui.QGraphicsEllipseItem(QtCore.QRectF(0, 0, self.size, self.size))
self.item.translate(-self.size*0.5, -self.size*0.5)
self.item.setPen(pg.mkPen(100,100,100))
self.item.setBrush(clock.brush)
self.hand = QtGui.QGraphicsLineItem(0, 0, 0, self.size*0.5)
self.hand.setPen(pg.mkPen('w'))
self.hand.setZValue(10)
self.flare = QtGui.QGraphicsPolygonItem(QtGui.QPolygonF([
QtCore.QPointF(0, -self.size*0.25),
QtCore.QPointF(0, self.size*0.25),
QtCore.QPointF(self.size*1.5, 0),
QtCore.QPointF(0, -self.size*0.25),
]))
self.flare.setPen(pg.mkPen('y'))
self.flare.setBrush(pg.mkBrush(255,150,0))
self.flare.setZValue(-10)
self.addItem(self.hand)
self.addItem(self.item)
self.addItem(self.flare)
self.clock = clock
self.i = 1
self._spaceline = None
def spaceline(self):
if self._spaceline is None:
self._spaceline = pg.InfiniteLine()
self._spaceline.setPen(self.clock.pen)
return self._spaceline
def stepTo(self, t):
data = self.clock.refData
while self.i < len(data)-1 and data['t'][self.i] < t:
self.i += 1
while self.i > 1 and data['t'][self.i-1] >= t:
self.i -= 1
self.setPos(data['x'][self.i], self.clock.y0)
t = data['pt'][self.i]
self.hand.setRotation(-0.25 * t * 360.)
self.resetTransform()
v = data['v'][self.i]
gam = (1.0 - v**2)**0.5
self.scale(gam, 1.0)
f = data['f'][self.i]
self.flare.resetTransform()
if f < 0:
self.flare.translate(self.size*0.4, 0)
else:
self.flare.translate(-self.size*0.4, 0)
self.flare.scale(-f * (0.5+np.random.random()*0.1), 1.0)
if self._spaceline is not None:
self._spaceline.setPos(pg.Point(data['x'][self.i], data['t'][self.i]))
self._spaceline.setAngle(data['v'][self.i] * 45.)
def reset(self):
self.i = 1
#class Spaceline(pg.InfiniteLine):
#def __init__(self, sim, frame):
#self.sim = sim
#self.frame = frame
#pg.InfiniteLine.__init__(self)
#self.setPen(sim.clocks[frame].pen)
#def stepTo(self, t):
#self.setAngle(0)
#pass
if __name__ == '__main__':
pg.mkQApp()
#import pyqtgraph.console
#cw = pyqtgraph.console.ConsoleWidget()
#cw.show()
#cw.catchNextException()
win = RelativityGUI()
win.setWindowTitle("Relativity!")
win.show()
win.resize(1100,700)
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui.QApplication.instance().exec_()
#win.params.param('Objects').restoreState(state, removeChildren=False)
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