def findHomotheticCenterOfCircles(circle1, circle2):
"""Calculate the homothetic center(s) of two circles.
http://en.wikipedia.org/wiki/Homothetic_center
http://mathworld.wolfram.com/HomotheticCenter.html
"""
if (geomType(circle1) == "Circle") and (geomType(circle2) == "Circle"):
if DraftVecUtils.equals(circle1.Curve.Center, circle2.Curve.Center):
return None
cen1_cen2 = Part.LineSegment(circle1.Curve.Center,
circle2.Curve.Center).toShape()
cenDir = vec(cen1_cen2)
cenDir.normalize()
# Get the perpedicular vector.
perpCenDir = cenDir.cross(Vector(0, 0, 1))
perpCenDir.normalize()
# Get point on first circle
p1 = Vector.add(circle1.Curve.Center,
Vector(perpCenDir).multiply(circle1.Curve.Radius))
centers = []
# Calculate inner homothetic center
# Get point on second circle
p2_inner = Vector.add(
circle1.Curve.Center,
Vector(perpCenDir).multiply(-circle1.Curve.Radius))
hCenterInner = DraftVecUtils.intersect(circle1.Curve.Center,
circle2.Curve.Center, p1,
p2_inner, True, True)
if hCenterInner:
centers.append(hCenterInner)
# Calculate outer homothetic center (only exists of the circles have different radii)
if circle1.Curve.Radius != circle2.Curve.Radius:
# Get point on second circle
p2_outer = Vector.add(
circle1.Curve.Center,
Vector(perpCenDir).multiply(circle1.Curve.Radius))
hCenterOuter = DraftVecUtils.intersect(circle1.Curve.Center,
circle2.Curve.Center, p1,
p2_outer, True, True)
if hCenterOuter:
centers.append(hCenterOuter)
if len(centers):
return centers
else:
return None
else:
FreeCAD.Console.PrintMessage(
"debug: findHomotheticCenterOfCirclescleFrom3tan bad parameters!\n"
)
return None
def findHomotheticCenterOfCircles(circle1, circle2):
"""Calculate the homothetic centers from two circles.
Return None if the objects are not circles, or if they are concentric.
http://en.wikipedia.org/wiki/Homothetic_center
http://mathworld.wolfram.com/HomotheticCenter.html
"""
if (geomType(circle1) == "Circle" and geomType(circle2) == "Circle"):
print("debug: findHomotheticCenterOfCircles bad parameters!")
return None
if DraftVecUtils.equals(circle1.Curve.Center,
circle2.Curve.Center):
return None
cen1_cen2 = Part.LineSegment(circle1.Curve.Center,
circle2.Curve.Center).toShape()
cenDir = vec(cen1_cen2)
cenDir.normalize()
# Get the perpedicular vector.
perpCenDir = cenDir.cross(App.Vector(0, 0, 1))
perpCenDir.normalize()
# Get point on first circle
p1 = App.Vector.add(circle1.Curve.Center,
App.Vector(perpCenDir).multiply(circle1.Curve.Radius))
centers = []
# Calculate inner homothetic center
# Get point on second circle
p2_inner = App.Vector.add(circle1.Curve.Center,
App.Vector(perpCenDir).multiply(-circle1.Curve.Radius))
hCenterInner = DraftVecUtils.intersect(circle1.Curve.Center,
circle2.Curve.Center,
p1, p2_inner,
True, True)
if hCenterInner:
centers.append(hCenterInner)
# Calculate outer homothetic center; it only exists if the circles
# have different radii
if circle1.Curve.Radius != circle2.Curve.Radius:
# Get point on second circle
p2_outer = App.Vector.add(circle1.Curve.Center,
App.Vector(perpCenDir).multiply(circle1.Curve.Radius))
hCenterOuter = DraftVecUtils.intersect(circle1.Curve.Center,
circle2.Curve.Center,
p1, p2_outer,
True, True)
if hCenterOuter:
centers.append(hCenterOuter)
if centers:
return centers
else:
return None
