def bend(self, amount):
"""Bend the line to the right by a given distance."""
if amount == 0:
self.arcthrupoint = None
return self
middle = self.p1.midpoint(self.p2)
nx = (middle.y() - self.p1.y()) / abs(self.p1.distance(middle))
ny = (self.p1.x() - middle.x()) / abs(self.p1.distance(middle))
vx = middle.x() - self.p1.x()
vy = middle.y() - self.p1.y()
if (vx * ny - vy * nx) > 0:
nx *= -1
ny *= -1
arcpoint = Point(middle.x() + amount * nx, middle.y() + amount * ny)
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(
pyx.path.line(middle.x(), middle.y(), arcpoint.x(),
arcpoint.y()), [color.rgb.blue])
self.arcThru(arcpoint)
if config.getOptions().DEBUG:
print(self.getVisiblePath())
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(
self.getVisiblePath(), [color.rgb.blue])
return self
def bend(self, amount):
"""Bend the line to the right by a given distance."""
middle = self.p1.midpoint(self.p2)
nx = (middle.y() - self.p1.y()) / abs(self.p1.distance(middle))
ny = (self.p1.x() - middle.x()) / abs(self.p1.distance(middle))
vx = middle.x() - self.p1.x()
vy = middle.y() - self.p1.y()
if (vx * ny - vy * nx) > 0:
nx *= -1
ny *= -1
arcpoint = Point(middle.x() + amount * nx, middle.y() + amount * ny)
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(
pyx.path.line(middle.x(), middle.y(), arcpoint.x(),
arcpoint.y()), [color.rgb.blue] )
self.arcThru(arcpoint)
if config.getOptions().DEBUG:
print self.getVisiblePath()
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(self.getVisiblePath(), [color.rgb.blue])
return self
def getPath(self):
"""Get the path taken by this line."""
if self.arcthrupoint is None:
## This is a simple straight line
return pyx.path.path( pyx.path.moveto( *(self.p1.getXY()) ),
pyx.path.lineto( *(self.p2.getXY()) ) )
elif (self.p1.x() == self.p2.x() and self.p1.y() == self.p2.y()):
## This is a tadpole-type loop and needs special care;
## We shall assume that the arcthrupoint is meant to be
## the antipode of the basepoint
arccenter = self.p1.midpoint(self.arcthrupoint)
arcradius = self.p1.distance(self.arcthrupoint) / 2.0
## TODO Why does a circle work and an arc doesn't?
cargs = (arccenter.x(), arccenter.y(), arcradius)
circle = pyx.path.circle(*cargs)
line = pyx.path.line( self.p1.x(), self.p1.y(), arccenter.x(), arccenter.y())
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(line, [color.rgb.green])
ass, bs = circle.intersect(line)
subpaths = circle.split(ass[0])
cpath = subpaths[0]
return cpath
## or, with an arc...
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p1) + 360
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
return pyx.path.path( pyx.path.arc(*arcargs) )
else:
n13, n23 = None, None
## Work out line gradients
try:
n13 = (self.p1.y() - self.arcthrupoint.y()) / (self.p1.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print("Grad 1 diverges")
n13 = 1e100
try:
n23 = (self.p2.y() - self.arcthrupoint.y()) / (self.p2.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print("Grad 2 diverges")
n23 = 1e100
## If gradients match,
## then we have a straight line, so bypass the complexity
if n13 == n23:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.lineto(*(self.p2.getXY())) )
## Otherwise work out conjugate gradients and midpoints
m13, m23 = None, None
try:
m13 = -1.0 / n13
except ZeroDivisionError:
m13 = 1e100
try:
m23 = -1.0 / n23
except ZeroDivisionError:
m23 = 1e100
mid13 = self.p1.midpoint(self.arcthrupoint)
mid23 = self.p2.midpoint(self.arcthrupoint)
## Line y-intercepts
c13 = mid13.y() - m13 * mid13.x()
c23 = mid23.y() - m23 * mid23.x()
## Find the centre of the arc
xcenter = - (c23 - c13) / (m23 - m13)
ycenter = m13 * xcenter + c13
arccenter = Point(xcenter, ycenter)
## Get the angles required for drawing the arc
arcradius = arccenter.distance(self.arcthrupoint)
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p2)
arcangle3 = arccenter.arg(self.arcthrupoint)
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
if config.getOptions().DEBUG and arcangle1 == arcangle2:
print("Arc angles are the same - not drawing anything")
## Calculate cross product to determine direction of arc
vec12 = [self.p2.x()-self.p1.x(), self.p2.y()-self.p1.y(), 0.0]
vec13 = [self.arcthrupoint.x()-self.p1.x(), self.arcthrupoint.y()-self.p1.y(), 0.0]
crossproductZcoord = vec12[0]*vec13[1] - vec12[1]*vec13[0]
if crossproductZcoord < 0:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arc(*arcargs))
else:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arcn(*arcargs))
class Line(Visible):
"Base class for all objects which connect points in Feynman diagrams"
def __init__(self, point1, point2, styles=[], arcthrupoint=None, is3D=False, arrows=[], labels=[], **kwargs):
"""Constructor."""
self.p1 = point1
self.p2 = point2
self.styles = styles
self.arcthrupoint = arcthrupoint
self.is3D = is3D
self.arrows = arrows
self.labels = labels
## Add this to the current diagram automatically
FeynDiagram.currentDiagram.add(self)
def addLabel(self, text, pos=0.5, displace=-0.25, angle = 0, size=pyx.text.size.normalsize, halign=CENTER, valign=None, **kwargs):
"""Add a LaTeX label to this line, either via parameters or actually as
a TeXLabel object."""
if config.getOptions().DEBUG:
print("Adding label: " + text)
#if text.__class__ == "Label":
# self.labels.append(label)
#else:
self.labels.append(LineLabel(text=text, line=self, pos=pos, displace=displace, angle=angle, size=size, halign=halign, valign=valign))
if config.getOptions().DEBUG:
print("Labels = " + str(self.labels))
return self
def addParallelArrow(self, pos=0.5, displace=0.3, length=0.5*pyx.unit.v_cm,
size=6*pyx.unit.v_pt, angle=45, constriction=0.8, sense=+1,
curved=False,stems=1,stemsep=0.03):
"""Add an arrow pointing along the line."""
self.labels.append(ParallelArrow(self, pos=pos, displace=displace,
length=length, size=size, angle=angle,
constriction=constriction,sense=sense,
curved=curved,stems=stems,
stemsep=stemsep))
return self
def removeLabels(self):
"""Remove the labels from this line."""
self.labels = []
return self
def fracpoint(self, frac):
"""
Get a new Point representing the point at the given fraction along
the fundamental line (i.e. no truncation or deformation).
TODO: Handle units properly.
"""
p = self.getPath() ## no truncation or deformation
x, y = p.at(p.begin() + frac * p.arclen())
return Point(x/defunit, y/defunit)
def setArrows(self, arrows):
"""Define the arrows on this line."""
## TODO: Check that the arg is a list
self.arrows = []
for i in arrows:
if i.__class__ == "deco.Arrow":
self.arrows.append(i)
else:
self.arrows.append(Arrow(pos = i))
return self
def addArrow(self, position = 0.53, arrow = None):
"""Add an arrow to the line at the specified position, which is a number
between 0 and 1, representing the fraction along the line at which the
arrow should be placed. The default arrow style can be overridden by
explicitly supplying an arrow object as the 'arrow' argument, in which
case the position argument will be ignored."""
if arrow:
self.arrows.append(arrow)
else:
self.arrows.append(Arrow(pos=position))
return self
def removeArrows(self):
"""Remove all arrows from this line."""
self.arrows = []
return self
def arcThru(self, arcpoint = None, x = None, y = None):
"""Set the point through which this line will arc. Either pass a Point
or set x, y as floats."""
if arcpoint is not None:
self.arcthrupoint = arcpoint
elif x is not None and y is not None:
self.arcthrupoint = Point(x, y)
else:
raise Exception("Tried to set an arcpoint with invalid arguments")
return self
def straighten(self):
"""Make this line a straight line between start and end."""
self.arcthrupoint = None
return self
def bend(self, amount):
"""Bend the line to the right by a given distance."""
if amount==0:
self.arcthrupoint = None
return self
middle = self.p1.midpoint(self.p2)
nx = (middle.y() - self.p1.y()) / abs(self.p1.distance(middle))
ny = (self.p1.x() - middle.x()) / abs(self.p1.distance(middle))
vx = middle.x() - self.p1.x()
vy = middle.y() - self.p1.y()
if (vx * ny - vy * nx) > 0:
nx *= -1
ny *= -1
arcpoint = Point(middle.x() + amount * nx, middle.y() + amount * ny)
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(
pyx.path.line(middle.x(), middle.y(), arcpoint.x(),
arcpoint.y()), [color.rgb.blue] )
self.arcThru(arcpoint)
if config.getOptions().DEBUG:
print(self.getVisiblePath())
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(self.getVisiblePath(), [color.rgb.blue])
return self
def set3D(self, choice):
"""Make this line display in '3D'."""
self.is3D = choice
return self
def getStyles(self, stylelist):
"""Get the styles associated with this line."""
return self.styles
def setStyles(self, stylelist):
"""Set the styles associated with this line."""
self.styles = stylelist
return self
def addStyle(self, style):
"""Add a style to this line."""
self.styles.append(style)
return self
def addStyles(self, stylelist):
"""Add some styles to this line."""
self.styles = self.styles + stylelist
return self
def getPath(self):
"""Get the path taken by this line."""
if self.arcthrupoint is None:
## This is a simple straight line
return pyx.path.path( pyx.path.moveto( *(self.p1.getXY()) ),
pyx.path.lineto( *(self.p2.getXY()) ) )
elif (self.p1.x() == self.p2.x() and self.p1.y() == self.p2.y()):
## This is a tadpole-type loop and needs special care;
## We shall assume that the arcthrupoint is meant to be
## the antipode of the basepoint
arccenter = self.p1.midpoint(self.arcthrupoint)
arcradius = self.p1.distance(self.arcthrupoint) / 2.0
## TODO Why does a circle work and an arc doesn't?
cargs = (arccenter.x(), arccenter.y(), arcradius)
circle = pyx.path.circle(*cargs)
line = pyx.path.line( self.p1.x(), self.p1.y(), arccenter.x(), arccenter.y())
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(line, [color.rgb.green])
ass, bs = circle.intersect(line)
subpaths = circle.split(ass[0])
cpath = subpaths[0]
return cpath
## or, with an arc...
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p1) + 360
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
return pyx.path.path( pyx.path.arc(*arcargs) )
else:
n13, n23 = None, None
## Work out line gradients
try:
n13 = (self.p1.y() - self.arcthrupoint.y()) / (self.p1.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print("Grad 1 diverges")
n13 = 1e100
try:
n23 = (self.p2.y() - self.arcthrupoint.y()) / (self.p2.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print("Grad 2 diverges")
n23 = 1e100
## If gradients match,
## then we have a straight line, so bypass the complexity
if n13 == n23:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.lineto(*(self.p2.getXY())) )
## Otherwise work out conjugate gradients and midpoints
m13, m23 = None, None
try:
m13 = -1.0 / n13
except ZeroDivisionError:
m13 = 1e100
try:
m23 = -1.0 / n23
except ZeroDivisionError:
m23 = 1e100
mid13 = self.p1.midpoint(self.arcthrupoint)
mid23 = self.p2.midpoint(self.arcthrupoint)
## Line y-intercepts
c13 = mid13.y() - m13 * mid13.x()
c23 = mid23.y() - m23 * mid23.x()
## Find the centre of the arc
xcenter = - (c23 - c13) / (m23 - m13)
ycenter = m13 * xcenter + c13
arccenter = Point(xcenter, ycenter)
## Get the angles required for drawing the arc
arcradius = arccenter.distance(self.arcthrupoint)
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p2)
arcangle3 = arccenter.arg(self.arcthrupoint)
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
if config.getOptions().DEBUG and arcangle1 == arcangle2:
print("Arc angles are the same - not drawing anything")
## Calculate cross product to determine direction of arc
vec12 = [self.p2.x()-self.p1.x(), self.p2.y()-self.p1.y(), 0.0]
vec13 = [self.arcthrupoint.x()-self.p1.x(), self.arcthrupoint.y()-self.p1.y(), 0.0]
crossproductZcoord = vec12[0]*vec13[1] - vec12[1]*vec13[0]
if crossproductZcoord < 0:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arc(*arcargs))
else:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arcn(*arcargs))
def getVisiblePath(self):
"""Find the subpath between the endpoints which isn't overshadowed by a blob of some kind"""
p1path = self.p1.getPath()
p2path = self.p2.getPath()
vispath = self.getPath()
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(vispath, [color.rgb.green])
if p1path:
ass, bs = p1path.intersect(vispath)
for b in bs:
subpaths = vispath.split(b)
if len(subpaths) > 1:
if config.getOptions().DEBUG:
print("Num subpaths 1 = %d" % len(subpaths))
subpaths.sort(key=lambda x:pyx.unit.tocm(x.arclen()))
vispath = subpaths[-1]
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(subpaths[0], [color.rgb.blue])
if config.getOptions().VDEBUG:
for a in ass:
ix, iy = p1path.at(a)
FeynDiagram.currenDiagram.currentCanvas.fill(pyx.path.circle(ix, iy, 0.05),
[color.rgb.green])
if p2path:
ass, bs = p2path.intersect(vispath)
for b in bs:
subpaths = vispath.split(b)
if len(subpaths) > 1:
if config.getOptions().DEBUG:
print("Num subpaths 2 = %d" % len(subpaths))
subpaths.sort(key=lambda x:pyx.unit.tocm(x.arclen()))
vispath = subpaths[-1]
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(subpaths[0], [color.rgb.red])
if config.getOptions().VDEBUG:
for a in ass:
ix, iy = p2path.at(a)
FeynDiagram.currenDiagram.currentCanvas.fill(pyx.path.circle(ix, iy, 0.05),
[color.rgb.blue])
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(vispath, [color.rgb.red])
#return pyx.path.circle(-2,-1,0.2)
return vispath
def draw(self, canvas):
"""Drwa this line on the given canvas."""
path = self.getVisiblePath()
styles = self.styles + self.arrows
if config.getOptions().DEBUG:
print("Drawing " + str(self.__class__) + " with styles = " + str(styles))
print(path)
canvas.stroke(path, styles)
for l in self.labels:
l.draw(canvas)
def getPath(self):
"""Get the path taken by this line."""
if self.arcthrupoint is None:
## This is a simple straight line
return pyx.path.path( pyx.path.moveto( *(self.p1.getXY()) ),
pyx.path.lineto( *(self.p2.getXY()) ) )
elif (self.p1.x() == self.p2.x() and self.p1.y() == self.p2.y()):
## This is a tadpole-type loop and needs special care;
## We shall assume that the arcthrupoint is meant to be
## the antipode of the basepoint
arccenter = self.p1.midpoint(self.arcthrupoint)
arcradius = self.p1.distance(self.arcthrupoint) / 2.0
## TODO Why does a circle work and an arc doesn't?
cargs = (arccenter.x(), arccenter.y(), arcradius)
circle = pyx.path.circle(*cargs)
line = pyx.path.line( self.p1.x(), self.p1.y(), arccenter.x(), arccenter.y())
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(line, [color.rgb.green])
ass, bs = circle.intersect(line)
subpaths = circle.split(ass[0])
cpath = subpaths[0]
return cpath
## or, with an arc...
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p1) + 360
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
return pyx.path.path( pyx.path.arc(*arcargs) )
else:
n13, n23 = None, None
## Work out line gradients
try:
n13 = (self.p1.y() - self.arcthrupoint.y()) / (self.p1.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print "Grad 1 diverges"
n13 = 1e100
try:
n23 = (self.p2.y() - self.arcthrupoint.y()) / (self.p2.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print "Grad 2 diverges"
n23 = 1e100
## If gradients match,
## then we have a straight line, so bypass the complexity
if n13 == n23:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.lineto(*(self.p2.getXY())) )
## Otherwise work out conjugate gradients and midpoints
m13, m23 = None, None
try:
m13 = -1.0 / n13
except ZeroDivisionError:
m13 = 1e100
try:
m23 = -1.0 / n23
except ZeroDivisionError:
m23 = 1e100
mid13 = self.p1.midpoint(self.arcthrupoint)
mid23 = self.p2.midpoint(self.arcthrupoint)
## Line y-intercepts
c13 = mid13.y() - m13 * mid13.x()
c23 = mid23.y() - m23 * mid23.x()
## Find the centre of the arc
xcenter = - (c23 - c13) / (m23 - m13)
ycenter = m13 * xcenter + c13
arccenter = Point(xcenter, ycenter)
## Get the angles required for drawing the arc
arcradius = arccenter.distance(self.arcthrupoint)
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p2)
arcangle3 = arccenter.arg(self.arcthrupoint)
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
if config.getOptions().DEBUG and arcangle1 == arcangle2:
print "Arc angles are the same - not drawing anything"
## Calculate cross product to determine direction of arc
vec12 = [self.p2.x()-self.p1.x(), self.p2.y()-self.p1.y(), 0.0]
vec13 = [self.arcthrupoint.x()-self.p1.x(), self.arcthrupoint.y()-self.p1.y(), 0.0]
crossproductZcoord = vec12[0]*vec13[1] - vec12[1]*vec13[0]
if crossproductZcoord < 0:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arc(*arcargs))
else:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arcn(*arcargs))
class Line(Visible):
"Base class for all objects which connect points in Feynman diagrams"
def __init__(self, point1, point2):
"""Constructor."""
self.p1 = point1
self.p2 = point2
self.styles = []
self.arcthrupoint = None
self.is3D = False
self.arrows = []
self.labels = []
## Add this to the current diagram automatically
FeynDiagram.currentDiagram.add(self)
def addLabel(self, text, pos=0.5, displace=-0.25, angle = 0, size=pyx.text.size.normalsize):
"""Add a LaTeX label to this line, either via parameters or actually as
a TeXLable object."""
if config.getOptions().DEBUG:
print "Adding label: " + text
#if text.__class__ == "Label":
# self.labels.append(label)
#else:
self.labels.append(LineLabel(text=text, line=self, pos=pos, displace=displace, angle=angle, size=size))
if config.getOptions().DEBUG:
print "Labels = " + str(self.labels)
return self
def addParallelArrow(self, pos=0.5, displace=0.3, length=0.5*pyx.unit.v_cm,
size=6*pyx.unit.v_pt, angle=45, constriction=0.8, sense=+1,
curved=False,stems=1,stemsep=0.03, rotation=0):
"""Add an arrow pointing along the line."""
self.labels.append(ParallelArrow(self, pos=pos, displace=displace,
length=length, size=size, angle=angle,
constriction=constriction,sense=sense,
curved=curved,stems=stems,
stemsep=stemsep, rotation=rotation))
return self
def removeLabels(self):
"""Remove the labels from this line."""
self.labels = []
return self
def fracpoint(self, frac):
"""
Get a new Point representing the point at the given fraction along
the fundamental line (i.e. no truncation or deformation).
TODO: Handle units properly.
"""
p = self.getPath() ## no truncation or deformation
x, y = p.at(p.begin() + frac * p.arclen())
return Point(x/defunit, y/defunit)
def setArrows(self, arrows):
"""Define the arrows on this line."""
## TODO: Check that the arg is a list
self.arrows = []
for i in arrows:
if i.__class__ == "deco.Arrow":
self.arrows.append(i)
else:
self.arrows.append(Arrow(pos = i))
return self
def addArrow(self, position = 0.53, arrow = None):
"""Add an arrow to the line at the specified position, which is a number
between 0 and 1, representing the fraction along the line at which the
arrow should be placed. The default arrow style can be overridden by
explicitly supplying an arrow object as the 'arrow' argument, in which
case the position argument will be ignored."""
if arrow:
self.arrows.append(arrow)
else:
self.arrows.append(Arrow(pos=position))
return self
def removeArrows(self):
"""Remove all arrows from this line."""
self.arrows = []
return self
def arcThru(self, arcpoint = None, x = None, y = None):
"""Set the point through which this line will arc. Either pass a Point
or set x, y as floats."""
if arcpoint is not None:
self.arcthrupoint = arcpoint
elif x is not None and y is not None:
self.arcthrupoint = Point(x, y)
else:
raise Exception("Tried to set an arcpoint with invalid arguments")
return self
def straighten(self):
"""Make this line a straight line between start and end."""
self.arcthrupoint = None
def bend(self, amount):
"""Bend the line to the right by a given distance."""
middle = self.p1.midpoint(self.p2)
nx = (middle.y() - self.p1.y()) / abs(self.p1.distance(middle))
ny = (self.p1.x() - middle.x()) / abs(self.p1.distance(middle))
vx = middle.x() - self.p1.x()
vy = middle.y() - self.p1.y()
if (vx * ny - vy * nx) > 0:
nx *= -1
ny *= -1
arcpoint = Point(middle.x() + amount * nx, middle.y() + amount * ny)
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(
pyx.path.line(middle.x(), middle.y(), arcpoint.x(),
arcpoint.y()), [color.rgb.blue] )
self.arcThru(arcpoint)
if config.getOptions().DEBUG:
print self.getVisiblePath()
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(self.getVisiblePath(), [color.rgb.blue])
return self
def set3D(self, choice):
"""Make this line display in '3D'."""
self.is3D = choice
return self
def getStyles(self, stylelist):
"""Get the styles associated with this line."""
return self.styles
def setStyles(self, stylelist):
"""Set the styles associated with this line."""
self.styles = stylelist
return self
def addStyle(self, style):
"""Add a style to this line."""
self.styles.append(style)
return self
def addStyles(self, stylelist):
"""Add some styles to this line."""
self.styles = self.styles + stylelist
return self
def getPath(self):
"""Get the path taken by this line."""
if self.arcthrupoint is None:
## This is a simple straight line
return pyx.path.path( pyx.path.moveto( *(self.p1.getXY()) ),
pyx.path.lineto( *(self.p2.getXY()) ) )
elif (self.p1.x() == self.p2.x() and self.p1.y() == self.p2.y()):
## This is a tadpole-type loop and needs special care;
## We shall assume that the arcthrupoint is meant to be
## the antipode of the basepoint
arccenter = self.p1.midpoint(self.arcthrupoint)
arcradius = self.p1.distance(self.arcthrupoint) / 2.0
## TODO Why does a circle work and an arc doesn't?
cargs = (arccenter.x(), arccenter.y(), arcradius)
circle = pyx.path.circle(*cargs)
line = pyx.path.line( self.p1.x(), self.p1.y(), arccenter.x(), arccenter.y())
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(line, [color.rgb.green])
ass, bs = circle.intersect(line)
subpaths = circle.split(ass[0])
cpath = subpaths[0]
return cpath
## or, with an arc...
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p1) + 360
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
return pyx.path.path( pyx.path.arc(*arcargs) )
else:
n13, n23 = None, None
## Work out line gradients
try:
n13 = (self.p1.y() - self.arcthrupoint.y()) / (self.p1.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print "Grad 1 diverges"
n13 = 1e100
try:
n23 = (self.p2.y() - self.arcthrupoint.y()) / (self.p2.x() - self.arcthrupoint.x())
except ZeroDivisionError:
if config.getOptions().DEBUG:
print "Grad 2 diverges"
n23 = 1e100
## If gradients match,
## then we have a straight line, so bypass the complexity
if n13 == n23:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.lineto(*(self.p2.getXY())) )
## Otherwise work out conjugate gradients and midpoints
m13, m23 = None, None
try:
m13 = -1.0 / n13
except ZeroDivisionError:
m13 = 1e100
try:
m23 = -1.0 / n23
except ZeroDivisionError:
m23 = 1e100
mid13 = self.p1.midpoint(self.arcthrupoint)
mid23 = self.p2.midpoint(self.arcthrupoint)
## Line y-intercepts
c13 = mid13.y() - m13 * mid13.x()
c23 = mid23.y() - m23 * mid23.x()
## Find the centre of the arc
xcenter = - (c23 - c13) / (m23 - m13)
ycenter = m13 * xcenter + c13
arccenter = Point(xcenter, ycenter)
## Get the angles required for drawing the arc
arcradius = arccenter.distance(self.arcthrupoint)
arcangle1 = arccenter.arg(self.p1)
arcangle2 = arccenter.arg(self.p2)
arcangle3 = arccenter.arg(self.arcthrupoint)
arcargs = (arccenter.x(), arccenter.y(), arcradius, arcangle1, arcangle2)
if config.getOptions().DEBUG and arcangle1 == arcangle2:
print "Arc angles are the same - not drawing anything"
## Calculate cross product to determine direction of arc
vec12 = [self.p2.x()-self.p1.x(), self.p2.y()-self.p1.y(), 0.0]
vec13 = [self.arcthrupoint.x()-self.p1.x(), self.arcthrupoint.y()-self.p1.y(), 0.0]
crossproductZcoord = vec12[0]*vec13[1] - vec12[1]*vec13[0]
if crossproductZcoord < 0:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arc(*arcargs))
else:
return pyx.path.path( pyx.path.moveto(*(self.p1.getXY())),
pyx.path.arcn(*arcargs))
def getVisiblePath(self):
"""Find the subpath between the endpoints which isn't overshadowed by a blob of some kind"""
p1path = self.p1.getPath()
p2path = self.p2.getPath()
vispath = self.getPath()
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(vispath, [color.rgb.green])
if p1path:
ass, bs = p1path.intersect(vispath)
for b in bs:
subpaths = vispath.split(b)
if len(subpaths) > 1:
if config.getOptions().DEBUG:
print "Num subpaths 1 = %d" % len(subpaths)
subpaths.sort(
lambda x, y :
int(pyx.unit.tocm(x.arclen() - y.arclen()) /
math.fabs(pyx.unit.tocm(x.arclen() - y.arclen()))) )
vispath = subpaths[-1]
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(subpaths[0], [color.rgb.blue])
if config.getOptions().VDEBUG:
for a in ass:
ix, iy = p1path.at(a)
FeynDiagram.currenDiagram.currentCanvas.fill(pyx.path.circle(ix, iy, 0.05),
[color.rgb.green])
if p2path:
ass, bs = p2path.intersect(vispath)
for b in bs:
subpaths = vispath.split(b)
if len(subpaths) > 1:
if config.getOptions().DEBUG:
print "Num subpaths 2 = %d" % len(subpaths)
subpaths.sort(
lambda x, y :
int(pyx.unit.tocm(x.arclen() - y.arclen()) /
math.fabs(pyx.unit.tocm(x.arclen() - y.arclen()))) )
vispath = subpaths[-1]
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(subpaths[0], [color.rgb.red])
if config.getOptions().VDEBUG:
for a in ass:
ix, iy = p2path.at(a)
FeynDiagram.currenDiagram.currentCanvas.fill(pyx.path.circle(ix, iy, 0.05),
[color.rgb.blue])
if config.getOptions().VDEBUG:
FeynDiagram.currenDiagram.currentCanvas.stroke(vispath, [color.rgb.red])
#return pyx.path.circle(-2,-1,0.2)
return vispath
def draw(self, canvas):
"""Drwa this line on the given canvas."""
path = self.getVisiblePath()
styles = self.styles + self.arrows
if config.getOptions().DEBUG:
print "Drawing " + str(self.__class__) + " with styles = " + str(styles)
print path
canvas.stroke(path, styles)
for l in self.labels:
l.draw(canvas)