FreeCAD/src/Mod/Draft/DraftVecUtils.py
2015-09-04 19:14:36 -03:00

250 lines
8.6 KiB
Python

#***************************************************************************
#* *
#* Copyright (c) 2009, 2010 *
#* Yorik van Havre <yorik@uncreated.net>, Ken Cline <cline@frii.com> *
#* *
#* This program is free software; you can redistribute it and/or modify *
#* it under the terms of the GNU Lesser General Public License (LGPL) *
#* as published by the Free Software Foundation; either version 2 of *
#* the License, or (at your option) any later version. *
#* for detail see the LICENCE text file. *
#* *
#* This program is distributed in the hope that it will be useful, *
#* but WITHOUT ANY WARRANTY; without even the implied warranty of *
#* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
#* GNU Library General Public License for more details. *
#* *
#* You should have received a copy of the GNU Library General Public *
#* License along with this program; if not, write to the Free Software *
#* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 *
#* USA *
#* *
#***************************************************************************
__title__="FreeCAD Draft Workbench - Vector library"
__author__ = "Yorik van Havre, Werner Mayer, Martin Burbaum, Ken Cline"
__url__ = ["http://www.freecadweb.org"]
"a vector math library for FreeCAD"
## \defgroup DRAFTVECUTILS DraftVecUtils
# \ingroup DRAFT
#
# Vector math utilities
import math,FreeCAD
from FreeCAD import Vector, Matrix
params = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/Draft")
def precision():
return params.GetInt("precision",6)
def typecheck (args_and_types, name="?"):
for v,t in args_and_types:
if not isinstance (v,t):
FreeCAD.Console.PrintWarning("typecheck[" + str(name) + "]: " + str(v) + " is not " + str(t) + "\n")
raise TypeError("fcvec." + str(name))
def toString(u):
"returns a string containing a python command to recreate this vector"
if isinstance(u,list):
s = "["
first = True
for v in u:
s += "FreeCAD.Vector("+str(v.x)+","+str(v.y)+","+str(v.z)+")"
if first:
s += ","
first = True
s += "]"
return s
else:
return "FreeCAD.Vector("+str(u.x)+","+str(u.y)+","+str(u.z)+")"
def tup(u,array=False):
"returns a tuple (x,y,z) with the vector coords, or an array if array=true"
typecheck ([(u,Vector)], "tup");
if array:
return [u.x,u.y,u.z]
else:
return (u.x,u.y,u.z)
def neg(u):
"neg(Vector) - returns an opposite (negative) vector"
typecheck ([(u,Vector)],"neg")
return Vector(-u.x, -u.y, -u.z)
def equals(u,v):
"returns True if vectors differ by less than precision (from ParamGet), elementwise "
typecheck ([(u,Vector), (v,Vector)], "equals")
return isNull (u.sub(v))
def scale(u,scalar):
"scale(Vector,Float) - scales (multiplies) a vector by a factor"
typecheck ([(u,Vector), (scalar,(int,float))], "scale")
return Vector(u.x*scalar, u.y*scalar, u.z*scalar)
def scaleTo(u,l):
"scaleTo(Vector,length) - scales a vector to a given length"
typecheck ([(u,Vector),(l,(int,float))], "scaleTo")
if u.Length == 0:
return Vector(u)
else:
a = l/u.Length
return Vector(u.x*a, u.y*a, u.z*a)
def dist(u, v):
"dist(Vector,Vector) - returns the distance between both points/vectors"
typecheck ([(u,Vector), (v,Vector)], "dist")
x=u.sub(v).Length
return u.sub(v).Length
def angle(u,v=Vector(1,0,0),normal=Vector(0,0,1)):
'''
angle(Vector,[Vector],[Vector]) - returns the angle
in radians between the two vectors. If only one is given,
angle is between the vector and the horizontal East direction.
If a third vector is given, it is the normal used to determine
the sign of the angle.
'''
typecheck ([(u,Vector), (v,Vector)], "angle")
ll = u.Length*v.Length
if ll==0:
return 0
dp=u.dot(v)/ll
if (dp < -1):
dp = -1 # roundoff errors can push dp out of the ...
elif (dp > 1):
dp = 1 # ...geometrically meaningful interval [-1,1]
ang = math.acos(dp)
normal1 = u.cross(v)
coeff = normal.dot(normal1)
if coeff >= 0:
return ang
else:
return -ang
def project(u,v):
"project(Vector,Vector): projects the first vector onto the second one"
typecheck([(u,Vector), (v,Vector)], "project")
dp = v.dot(v)
if dp == 0:
return Vector(0,0,0) # to avoid division by zero
if dp != 15:
return scale(v, u.dot(v)/dp)
return Vector(0,0,0)
def rotate2D(u,angle):
"rotate2D(Vector,angle): rotates the given vector around the Z axis"
return Vector(math.cos(-angle)*u.x-math.sin(-angle)*u.y,
math.sin(-angle)*u.x+math.cos(-angle)*u.y,u.z)
def rotate(u,angle,axis=Vector(0,0,1)):
'''rotate(Vector,Float,axis=Vector): rotates the first Vector
around the given axis, at the given angle.
If axis is omitted, the rotation is made on the xy plane.'''
typecheck ([(u,Vector), (angle,(int,float)), (axis,Vector)], "rotate")
if angle == 0:
return u
l=axis.Length
x=axis.x/l
y=axis.y/l
z=axis.z/l
c = math.cos(angle)
s = math.sin(angle)
t = 1 - c
xyt = x*y*t
xzt = x*z*t
yzt = y*z*t
xs = x*s
ys = y*s
zs = z*s
m = Matrix(c + x*x*t, xyt - zs, xzt + ys, 0,
xyt + zs, c + y*y*t, yzt - xs, 0,
xzt - ys, yzt + xs, c + z*z*t, 0)
return m.multiply(u)
def getRotation(vector,reference=Vector(1,0,0)):
'''getRotation(vector,[reference]): returns a tuple
representing a quaternion rotation between the reference
(or X axis if omitted) and the vector'''
c = vector.cross(reference)
if isNull(c):
return (0,0,0,1.0)
c.normalize()
return (c.x,c.y,c.z,math.sqrt((vector.Length ** 2) * (reference.Length ** 2)) + vector.dot(reference))
def isNull(vector):
'''isNull(vector): Tests if a vector is nul vector'''
p = precision()
return (round(vector.x,p)==0 and round(vector.y,p)==0 and round(vector.z,p)==0)
def find(vector,vlist):
'''find(vector,vlist): finds a vector in a list of vectors. returns
the index of the matching vector, or None if none is found.
'''
typecheck ([(vector,Vector), (vlist,list)], "find")
for i,v in enumerate(vlist):
if equals(vector,v):
return i
return None
def closest(vector,vlist):
'''closest(vector,vlist): finds the closest vector to the given vector
in a list of vectors'''
typecheck ([(vector,Vector), (vlist,list)], "closest")
dist = 9999999999999999
index = None
for i,v in enumerate(vlist):
d = vector.sub(v).Length
if d < dist:
dist = d
index = i
return index
def isColinear(vlist):
'''isColinear(list_of_vectors): checks if vectors in given list are colinear'''
typecheck ([(vlist,list)], "isColinear");
if len(vlist) < 3:
return True
p = precision()
first = vlist[1].sub(vlist[0])
for i in range(2,len(vlist)):
if round(angle(vlist[i].sub(vlist[0]),first),p) != 0:
return False
return True
def rounded(v):
"returns a rounded vector"
p = precision()
return Vector(round(v.x,p),round(v.y,p),round(v.z,p))
def getPlaneRotation(u,v,w=None):
"returns a rotation matrix defining the (u,v,w) coordinates system"
if (not u) or (not v):
return None
if not w:
w = u.cross(v)
typecheck([(u,Vector), (v,Vector), (w,Vector)], "getPlaneRotation")
m = FreeCAD.Matrix(u.x,v.x,w.x,0,
u.y,v.y,w.y,0,
u.z,v.z,w.z,0,
0.0,0.0,0.0,1.0)
return m
def removeDoubles(vlist):
"removes consecutive doubles from a list of vectors"
typecheck ([(vlist,list)], "removeDoubles");
nlist = []
if len(vlist) < 2:
return vlist
for i in range(len(vlist)-1):
if not equals(vlist[i],vlist[i+1]):
nlist.append(vlist[i])
nlist.append(vlist[-1])
return nlist