add fcgear

http://forum.freecadweb.org/viewtopic.php?f=9&t=5703

src/Mod/PartDesign/CMakeLists.txt

@@ -27,6 +27,18 @@ INSTALL(
         Scripts/Spring.py
     DESTINATION
         Mod/PartDesign/Scripts
+       )
+
+INSTALL(
+    FILES
+        fcgear/__init__.py
+        fcgear/fcgear.py
+        fcgear/fcgeardialog.py
+        fcgear/involute.py
+        fcgear/svggear.py
+    DESTINATION
+        Mod/PartDesign/fcgear
+
 )
 
 SET(WizardShaft_SRCS

src/Mod/PartDesign/fcgear/README

@@ -0,0 +1,30 @@
+================================================
+ FCGear: an Involute Gear Generator for FreeCAD
+================================================
+
+This is a simple gear generation tool usable in FreeCAD. The tooth
+profiles are approximations of the ideal involutes by Bezier curves,
+according the paper:
+
+  Approximation of Involute Curves for CAD-System Processing
+  Higuchi et al. approximation to an involute.
+  ref: YNU Digital Eng Lab Memorandum 05-1
+  http://maekawalab-ynu.com/papers.html
+
+This code is based on the JavaScript implementation of the published
+method provided by A.R. Collins in his gearUtils.js tool:
+
+  Based on gearUtils-03.js by Dr A.R.Collins
+  Latest version:  <www.arc.id.au/gearDrawing.html>
+
+Also took inspirations from the Inkscape extension provided by Matthew
+Dockrey on
+
+  https://github.com/attoparsec/inkscape-extensions.git
+
+The simplest way to use it is to copy the example macro file
+gear.FCMacro to ~/.FreeCAD/ (make sure the fcgear directory is in the
+FreeCAD's Python path).
+
+Copyright 2014 David Douard <david.douard@gmail.com>.
+Distributed under the LGPL licence.

src/Mod/PartDesign/fcgear/fcgear.py

@@ -0,0 +1,108 @@
+# (c) 2014 David Douard <david.douard@gmail.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.
+#
+#   FCGear 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 FCGear; if not, write to the Free Software
+#   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+
+from math import cos, sin, pi, acos, asin, atan, sqrt
+
+import FreeCAD, FreeCADGui, Part
+from FreeCAD import Base, Console
+import involute
+reload(involute)
+rotate = involute.rotate
+
+
+def makeGear(m, Z, angle, split=True):
+    if FreeCAD.ActiveDocument is None:
+        FreeCAD.newDocument("Gear")
+    doc = FreeCAD.ActiveDocument
+    w = FCWireBuilder()
+    involute.CreateExternalGear(w, m, Z, angle, split)
+    gearw = Part.Wire([o.toShape() for o in w.wire])
+    gear = doc.addObject("Part::Feature", "Gear")
+    gear.Shape = gearw
+    return gear
+
+
+class FCWireBuilder(object):
+    """A helper class to prepare a Part.Wire object"""
+    def __init__(self):
+        self.pos = None
+        self.theta = 0.0
+        self.wire = []
+
+    def move(self, p):
+        """set current position"""
+        self.pos = Base.Vector(*p)
+
+    def line(self, p):
+        """Add a segment between self.pos and p"""
+        p = rotate(p, self.theta)
+        end = Base.Vector(*p)
+        self.wire.append(Part.Line(self.pos, end))
+        self.pos = end
+
+    def arc(self, p, r, sweep):
+        """"Add an arc from self.pos to p which radius is r
+        sweep (0 or 1) determine the orientation of the arc
+        """
+        p = rotate(p, self.theta)
+        end = Base.Vector(*p)
+        mid = Base.Vector(*(midpoints(p, self.pos, r)[sweep]))
+        self.wire.append(Part.Arc(self.pos, mid, end))
+        self.pos = end
+
+    def curve(self, *points):
+        """Add a Bezier curve from self.pos to points[-1]
+        every other points are the control points of the Bezier curve (which
+        will thus be of degree len(points) )
+        """
+        points = [Base.Vector(*rotate(p, self.theta)) for p in points]
+        bz = Part.BezierCurve()
+        bz.setPoles([self.pos] + points)
+        self.wire.append(bz)
+        self.pos = points[-1]
+
+    def close(self):
+        pass
+
+def midpoints(p1, p2, r):
+    """A very ugly function that returns the midpoint of a p1 and p2
+    on the circle which radius is r and which pass throught p1 and
+    p2
+
+    Return the 2 possible solutions
+    """
+    vx, vy = p2[0]-p1[0], p2[1]-p1[1]
+    b = (vx**2 + vy**2)**.5
+    v = (vx/b, vy/b)
+    cosA = b**2 / (2*b*r)
+    A = acos(cosA)
+
+    vx, vy = rotate(v, A)
+    c1 = (p1[0]+r*vx, p1[1]+r*vy)
+    m1x, m1y = ((p1[0]+p2[0])/2 - c1[0], (p1[1]+p2[1])/2 - c1[1])
+    dm1 = (m1x**2+m1y**2)**.5
+    m1x, m1y = (c1[0] + r*m1x/dm1, c1[1] + r*m1y/dm1)
+    m1 = (m1x, m1y)
+
+    vx, vy = rotate(v, -A)
+    c2 = (p1[0]+r*vx, p1[1]+r*vy)
+    m2x, m2y = ((p1[0]+p2[0])/2 - c2[0], (p1[1]+p2[1])/2 - c2[1])
+    dm2 = (m2x**2+m2y**2)**.5
+    m2x, m2y = (c2[0] + r*m2x/dm2, c2[1] + r*m2y/dm2)
+    m2 = (m2x, m2y)
+
+    return m1, m2

src/Mod/PartDesign/fcgear/fcgeardialog.py

@@ -0,0 +1,67 @@
+# (c) 2014 David Douard <david.douard@gmail.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.
+#
+#   FCGear 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 FCGear; if not, write to the Free Software
+#   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+
+from PyQt4 import QtGui as qt
+import fcgear
+import FreeCAD, FreeCADGui
+
+class GearCreationFrame(qt.QFrame):
+    def __init__(self, parent=None):
+        super(GearCreationFrame, self).__init__(parent)
+        self.Z = qt.QSpinBox(value=26)
+        self.m = qt.QDoubleSpinBox(value=2.5)
+        self.angle = qt.QDoubleSpinBox(value=20)
+        self.split = qt.QComboBox()
+        self.split.addItems(['2x3', '1x4'])
+        l = qt.QFormLayout(self)
+        l.setFieldGrowthPolicy(l.ExpandingFieldsGrow)
+        l.addRow('Number of teeth:', self.Z)
+        l.addRow('Modules (mm):', self.m)
+        l.addRow('Pressure angle:', self.angle)
+        l.addRow('Number of curves:', self.split)
+
+class GearDialog(qt.QDialog):
+    def __init__(self, parent=None):
+        super(GearDialog, self).__init__(parent)
+        self.gc = GearCreationFrame()
+
+        btns = qt.QDialogButtonBox.Ok | qt.QDialogButtonBox.Cancel
+        buttonBox = qt.QDialogButtonBox(btns,
+                                        accepted=self.accept,
+                                        rejected=self.reject)
+        l = qt.QVBoxLayout(self)
+        l.addWidget(self.gc)
+        l.addWidget(buttonBox)
+        self.setWindowTitle('Gear cration dialog')
+
+    def accept(self):
+        if FreeCAD.ActiveDocument is None:
+            FreeCAD.newDocument("Gear")
+
+        gear = fcgear.makeGear(self.gc.m.value(),
+                               self.gc.Z.value(),
+                               self.gc.angle.value(),
+                               not self.gc.split.currentIndex())
+        FreeCADGui.SendMsgToActiveView("ViewFit")
+        return super(GearDialog, self).accept()
+
+
+if __name__ == '__main__':
+    a = qt.QApplication([])
+    w = GearDialog()
+    w.show()
+    a.exec_()