764 lines
28 KiB
Python
764 lines
28 KiB
Python
import numpy as np
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import collections
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import sys, os
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import pyqtgraph as pg
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from pyqtgraph.Qt import QtGui, QtCore
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from pyqtgraph.parametertree import Parameter, ParameterTree
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from pyqtgraph.parametertree import types as pTypes
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import pyqtgraph.configfile
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from pyqtgraph.python2_3 import xrange
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class RelativityGUI(QtGui.QWidget):
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def __init__(self):
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QtGui.QWidget.__init__(self)
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self.animations = []
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self.animTimer = QtCore.QTimer()
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self.animTimer.timeout.connect(self.stepAnimation)
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self.animTime = 0
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self.animDt = .016
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self.lastAnimTime = 0
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self.setupGUI()
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self.objectGroup = ObjectGroupParam()
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self.params = Parameter.create(name='params', type='group', children=[
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dict(name='Load Preset..', type='list', values=[]),
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#dict(name='Unit System', type='list', values=['', 'MKS']),
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dict(name='Duration', type='float', value=10.0, step=0.1, limits=[0.1, None]),
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dict(name='Reference Frame', type='list', values=[]),
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dict(name='Animate', type='bool', value=True),
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dict(name='Animation Speed', type='float', value=1.0, dec=True, step=0.1, limits=[0.0001, None]),
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dict(name='Recalculate Worldlines', type='action'),
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dict(name='Save', type='action'),
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dict(name='Load', type='action'),
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self.objectGroup,
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])
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self.tree.setParameters(self.params, showTop=False)
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self.params.param('Recalculate Worldlines').sigActivated.connect(self.recalculate)
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self.params.param('Save').sigActivated.connect(self.save)
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self.params.param('Load').sigActivated.connect(self.load)
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self.params.param('Load Preset..').sigValueChanged.connect(self.loadPreset)
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self.params.sigTreeStateChanged.connect(self.treeChanged)
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## read list of preset configs
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presetDir = os.path.join(os.path.abspath(os.path.dirname(sys.argv[0])), 'presets')
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if os.path.exists(presetDir):
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presets = [os.path.splitext(p)[0] for p in os.listdir(presetDir)]
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self.params.param('Load Preset..').setLimits(['']+presets)
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def setupGUI(self):
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self.layout = QtGui.QVBoxLayout()
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self.layout.setContentsMargins(0,0,0,0)
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self.setLayout(self.layout)
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self.splitter = QtGui.QSplitter()
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self.splitter.setOrientation(QtCore.Qt.Horizontal)
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self.layout.addWidget(self.splitter)
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self.tree = ParameterTree(showHeader=False)
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self.splitter.addWidget(self.tree)
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self.splitter2 = QtGui.QSplitter()
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self.splitter2.setOrientation(QtCore.Qt.Vertical)
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self.splitter.addWidget(self.splitter2)
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self.worldlinePlots = pg.GraphicsLayoutWidget()
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self.splitter2.addWidget(self.worldlinePlots)
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self.animationPlots = pg.GraphicsLayoutWidget()
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self.splitter2.addWidget(self.animationPlots)
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self.splitter2.setSizes([int(self.height()*0.8), int(self.height()*0.2)])
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self.inertWorldlinePlot = self.worldlinePlots.addPlot()
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self.refWorldlinePlot = self.worldlinePlots.addPlot()
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self.inertAnimationPlot = self.animationPlots.addPlot()
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self.inertAnimationPlot.setAspectLocked(1)
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self.refAnimationPlot = self.animationPlots.addPlot()
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self.refAnimationPlot.setAspectLocked(1)
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self.inertAnimationPlot.setXLink(self.inertWorldlinePlot)
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self.refAnimationPlot.setXLink(self.refWorldlinePlot)
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def recalculate(self):
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## build 2 sets of clocks
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clocks1 = collections.OrderedDict()
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clocks2 = collections.OrderedDict()
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for cl in self.params.param('Objects'):
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clocks1.update(cl.buildClocks())
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clocks2.update(cl.buildClocks())
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## Inertial simulation
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dt = self.animDt * self.params['Animation Speed']
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sim1 = Simulation(clocks1, ref=None, duration=self.params['Duration'], dt=dt)
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sim1.run()
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sim1.plot(self.inertWorldlinePlot)
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self.inertWorldlinePlot.autoRange(padding=0.1)
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## reference simulation
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ref = self.params['Reference Frame']
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dur = clocks1[ref].refData['pt'][-1] ## decide how long to run the reference simulation
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sim2 = Simulation(clocks2, ref=clocks2[ref], duration=dur, dt=dt)
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sim2.run()
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sim2.plot(self.refWorldlinePlot)
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self.refWorldlinePlot.autoRange(padding=0.1)
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## create animations
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self.refAnimationPlot.clear()
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self.inertAnimationPlot.clear()
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self.animTime = 0
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self.animations = [Animation(sim1), Animation(sim2)]
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self.inertAnimationPlot.addItem(self.animations[0])
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self.refAnimationPlot.addItem(self.animations[1])
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## create lines representing all that is visible to a particular reference
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#self.inertSpaceline = Spaceline(sim1, ref)
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#self.refSpaceline = Spaceline(sim2)
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self.inertWorldlinePlot.addItem(self.animations[0].items[ref].spaceline())
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self.refWorldlinePlot.addItem(self.animations[1].items[ref].spaceline())
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def setAnimation(self, a):
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if a:
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self.lastAnimTime = pg.ptime.time()
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self.animTimer.start(int(self.animDt*1000))
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else:
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self.animTimer.stop()
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def stepAnimation(self):
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now = pg.ptime.time()
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dt = (now-self.lastAnimTime) * self.params['Animation Speed']
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self.lastAnimTime = now
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self.animTime += dt
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if self.animTime > self.params['Duration']:
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self.animTime = 0
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for a in self.animations:
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a.restart()
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for a in self.animations:
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a.stepTo(self.animTime)
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def treeChanged(self, *args):
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clocks = []
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for c in self.params.param('Objects'):
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clocks.extend(c.clockNames())
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#for param, change, data in args[1]:
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#if change == 'childAdded':
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self.params.param('Reference Frame').setLimits(clocks)
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self.setAnimation(self.params['Animate'])
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def save(self):
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filename = pg.QtGui.QFileDialog.getSaveFileName(self, "Save State..", "untitled.cfg", "Config Files (*.cfg)")
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if isinstance(filename, tuple):
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filename = filename[0] # Qt4/5 API difference
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if filename == '':
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return
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state = self.params.saveState()
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pg.configfile.writeConfigFile(state, str(filename))
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def load(self):
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filename = pg.QtGui.QFileDialog.getOpenFileName(self, "Save State..", "", "Config Files (*.cfg)")
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if isinstance(filename, tuple):
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filename = filename[0] # Qt4/5 API difference
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if filename == '':
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return
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state = pg.configfile.readConfigFile(str(filename))
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self.loadState(state)
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def loadPreset(self, param, preset):
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if preset == '':
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return
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path = os.path.abspath(os.path.dirname(__file__))
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fn = os.path.join(path, 'presets', preset+".cfg")
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state = pg.configfile.readConfigFile(fn)
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self.loadState(state)
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def loadState(self, state):
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if 'Load Preset..' in state['children']:
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del state['children']['Load Preset..']['limits']
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del state['children']['Load Preset..']['value']
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self.params.param('Objects').clearChildren()
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self.params.restoreState(state, removeChildren=False)
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self.recalculate()
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class ObjectGroupParam(pTypes.GroupParameter):
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def __init__(self):
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pTypes.GroupParameter.__init__(self, name="Objects", addText="Add New..", addList=['Clock', 'Grid'])
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def addNew(self, typ):
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if typ == 'Clock':
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self.addChild(ClockParam())
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elif typ == 'Grid':
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self.addChild(GridParam())
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class ClockParam(pTypes.GroupParameter):
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def __init__(self, **kwds):
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defs = dict(name="Clock", autoIncrementName=True, renamable=True, removable=True, children=[
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dict(name='Initial Position', type='float', value=0.0, step=0.1),
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#dict(name='V0', type='float', value=0.0, step=0.1),
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AccelerationGroup(),
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dict(name='Rest Mass', type='float', value=1.0, step=0.1, limits=[1e-9, None]),
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dict(name='Color', type='color', value=(100,100,150)),
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dict(name='Size', type='float', value=0.5),
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dict(name='Vertical Position', type='float', value=0.0, step=0.1),
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])
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#defs.update(kwds)
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pTypes.GroupParameter.__init__(self, **defs)
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self.restoreState(kwds, removeChildren=False)
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def buildClocks(self):
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x0 = self['Initial Position']
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y0 = self['Vertical Position']
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color = self['Color']
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m = self['Rest Mass']
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size = self['Size']
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prog = self.param('Acceleration').generate()
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c = Clock(x0=x0, m0=m, y0=y0, color=color, prog=prog, size=size)
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return {self.name(): c}
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def clockNames(self):
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return [self.name()]
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pTypes.registerParameterType('Clock', ClockParam)
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class GridParam(pTypes.GroupParameter):
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def __init__(self, **kwds):
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defs = dict(name="Grid", autoIncrementName=True, renamable=True, removable=True, children=[
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dict(name='Number of Clocks', type='int', value=5, limits=[1, None]),
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dict(name='Spacing', type='float', value=1.0, step=0.1),
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ClockParam(name='ClockTemplate'),
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])
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#defs.update(kwds)
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pTypes.GroupParameter.__init__(self, **defs)
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self.restoreState(kwds, removeChildren=False)
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def buildClocks(self):
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clocks = {}
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template = self.param('ClockTemplate')
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spacing = self['Spacing']
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for i in range(self['Number of Clocks']):
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c = list(template.buildClocks().values())[0]
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c.x0 += i * spacing
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clocks[self.name() + '%02d' % i] = c
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return clocks
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def clockNames(self):
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return [self.name() + '%02d' % i for i in range(self['Number of Clocks'])]
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pTypes.registerParameterType('Grid', GridParam)
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class AccelerationGroup(pTypes.GroupParameter):
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def __init__(self, **kwds):
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defs = dict(name="Acceleration", addText="Add Command..")
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pTypes.GroupParameter.__init__(self, **defs)
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self.restoreState(kwds, removeChildren=False)
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def addNew(self):
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nextTime = 0.0
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if self.hasChildren():
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nextTime = self.children()[-1]['Proper Time'] + 1
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self.addChild(Parameter.create(name='Command', autoIncrementName=True, type=None, renamable=True, removable=True, children=[
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dict(name='Proper Time', type='float', value=nextTime),
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dict(name='Acceleration', type='float', value=0.0, step=0.1),
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]))
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def generate(self):
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prog = []
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for cmd in self:
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prog.append((cmd['Proper Time'], cmd['Acceleration']))
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return prog
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pTypes.registerParameterType('AccelerationGroup', AccelerationGroup)
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class Clock(object):
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nClocks = 0
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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):
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Clock.nClocks += 1
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self.pen = pg.mkPen(color)
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self.brush = pg.mkBrush(color)
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self.y0 = y0
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self.x0 = x0
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self.v0 = v0
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self.m0 = m0
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self.t0 = t0
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self.prog = prog
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self.size = size
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def init(self, nPts):
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## Keep records of object from inertial frame as well as reference frame
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self.inertData = np.empty(nPts, dtype=[('x', float), ('t', float), ('v', float), ('pt', float), ('m', float), ('f', float)])
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self.refData = np.empty(nPts, dtype=[('x', float), ('t', float), ('v', float), ('pt', float), ('m', float), ('f', float)])
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## Inertial frame variables
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self.x = self.x0
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self.v = self.v0
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self.m = self.m0
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self.t = 0.0 ## reference clock always starts at 0
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self.pt = self.t0 ## proper time starts at t0
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## reference frame variables
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self.refx = None
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self.refv = None
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self.refm = None
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self.reft = None
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self.recordFrame(0)
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def recordFrame(self, i):
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f = self.force()
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self.inertData[i] = (self.x, self.t, self.v, self.pt, self.m, f)
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self.refData[i] = (self.refx, self.reft, self.refv, self.pt, self.refm, f)
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def force(self, t=None):
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if len(self.prog) == 0:
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return 0.0
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if t is None:
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t = self.pt
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ret = 0.0
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for t1,f in self.prog:
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if t >= t1:
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ret = f
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return ret
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def acceleration(self, t=None):
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return self.force(t) / self.m0
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def accelLimits(self):
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## return the proper time values which bound the current acceleration command
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if len(self.prog) == 0:
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return -np.inf, np.inf
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t = self.pt
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ind = -1
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for i, v in enumerate(self.prog):
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t1,f = v
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if t >= t1:
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ind = i
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if ind == -1:
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return -np.inf, self.prog[0][0]
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elif ind == len(self.prog)-1:
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return self.prog[-1][0], np.inf
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else:
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return self.prog[ind][0], self.prog[ind+1][0]
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def getCurve(self, ref=True):
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if ref is False:
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data = self.inertData
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else:
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data = self.refData[1:]
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x = data['x']
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y = data['t']
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curve = pg.PlotCurveItem(x=x, y=y, pen=self.pen)
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#x = self.data['x'] - ref.data['x']
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#y = self.data['t']
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step = 1.0
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#mod = self.data['pt'] % step
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#inds = np.argwhere(abs(mod[1:] - mod[:-1]) > step*0.9)
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inds = [0]
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pt = data['pt']
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for i in range(1,len(pt)):
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diff = pt[i] - pt[inds[-1]]
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if abs(diff) >= step:
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inds.append(i)
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inds = np.array(inds)
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#t = self.data['t'][inds]
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#x = self.data['x'][inds]
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pts = []
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for i in inds:
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x = data['x'][i]
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y = data['t'][i]
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if i+1 < len(data):
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dpt = data['pt'][i+1]-data['pt'][i]
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dt = data['t'][i+1]-data['t'][i]
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else:
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dpt = 1
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if dpt > 0:
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c = pg.mkBrush((0,0,0))
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else:
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c = pg.mkBrush((200,200,200))
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pts.append({'pos': (x, y), 'brush': c})
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points = pg.ScatterPlotItem(pts, pen=self.pen, size=7)
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return curve, points
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class Simulation:
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def __init__(self, clocks, ref, duration, dt):
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self.clocks = clocks
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self.ref = ref
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self.duration = duration
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self.dt = dt
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@staticmethod
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def hypTStep(dt, v0, x0, tau0, g):
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## Hyperbolic step.
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## If an object has proper acceleration g and starts at position x0 with speed v0 and proper time tau0
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## as seen from an inertial frame, then return the new v, x, tau after time dt has elapsed.
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if g == 0:
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return v0, x0 + v0*dt, tau0 + dt * (1. - v0**2)**0.5
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v02 = v0**2
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g2 = g**2
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tinit = v0 / (g * (1 - v02)**0.5)
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B = (1 + (g2 * (dt+tinit)**2))**0.5
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v1 = g * (dt+tinit) / B
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dtau = (np.arcsinh(g * (dt+tinit)) - np.arcsinh(g * tinit)) / g
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tau1 = tau0 + dtau
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x1 = x0 + (1.0 / g) * ( B - 1. / (1.-v02)**0.5 )
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return v1, x1, tau1
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@staticmethod
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def tStep(dt, v0, x0, tau0, g):
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## Linear step.
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## Probably not as accurate as hyperbolic step, but certainly much faster.
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gamma = (1. - v0**2)**-0.5
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dtau = dt / gamma
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return v0 + dtau * g, x0 + v0*dt, tau0 + dtau
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@staticmethod
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def tauStep(dtau, v0, x0, t0, g):
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## linear step in proper time of clock.
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## If an object has proper acceleration g and starts at position x0 with speed v0 at time t0
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## as seen from an inertial frame, then return the new v, x, t after proper time dtau has elapsed.
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## Compute how much t will change given a proper-time step of dtau
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gamma = (1. - v0**2)**-0.5
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if g == 0:
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dt = dtau * gamma
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else:
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v0g = v0 * gamma
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dt = (np.sinh(dtau * g + np.arcsinh(v0g)) - v0g) / g
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#return v0 + dtau * g, x0 + v0*dt, t0 + dt
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v1, x1, t1 = Simulation.hypTStep(dt, v0, x0, t0, g)
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return v1, x1, t0+dt
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@staticmethod
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def hypIntersect(x0r, t0r, vr, x0, t0, v0, g):
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## given a reference clock (seen from inertial frame) has rx, rt, and rv,
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## and another clock starts at x0, t0, and v0, with acceleration g,
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## compute the intersection time of the object clock's hyperbolic path with
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## the reference plane.
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## I'm sure we can simplify this...
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|
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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.values():
|
|
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.values():
|
|
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.items():
|
|
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.values():
|
|
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.values():
|
|
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
|
|
|
|
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))
|
|
tr = QtGui.QTransform.fromTranslate(-self.size*0.5, -self.size*0.5)
|
|
self.item.setTransform(tr)
|
|
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.)
|
|
|
|
v = data['v'][self.i]
|
|
gam = (1.0 - v**2)**0.5
|
|
self.setTransform(QtGui.QTransform.fromScale(gam, 1.0))
|
|
|
|
f = data['f'][self.i]
|
|
tr = QtGui.QTransform()
|
|
if f < 0:
|
|
tr.translate(self.size*0.4, 0)
|
|
else:
|
|
tr.translate(-self.size*0.4, 0)
|
|
|
|
tr.scale(-f * (0.5+np.random.random()*0.1), 1.0)
|
|
self.flare.setTransform(tr)
|
|
|
|
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__':
|
|
app = pg.mkQApp()
|
|
#import pyqtgraph.console
|
|
#cw = pyqtgraph.console.ConsoleWidget()
|
|
#cw.show()
|
|
#cw.catchNextException()
|
|
win = RelativityGUI()
|
|
win.setWindowTitle("Relativity!")
|
|
win.show()
|
|
win.resize(1100,700)
|
|
|
|
pg.exec()
|