From 590994984f8bc78a7d5ce14615e9fb1c18cb8a47 Mon Sep 17 00:00:00 2001
From: looooo <sppedflyer@gmail.com>
Date: Thu, 16 Dec 2021 13:20:11 +0100
Subject: [PATCH] connector: add support for internal involute gears

---
 freecad/gears/connector.py | 42 ++++++++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 8 deletions(-)

diff --git a/freecad/gears/connector.py b/freecad/gears/connector.py
index f16d1bc..5633db4 100644
--- a/freecad/gears/connector.py
+++ b/freecad/gears/connector.py
@@ -21,7 +21,7 @@ import copy
 import numpy as np
 import FreeCAD
 from pygears import __version__
-from .features import InvoluteGear, CycloidGear, InvoluteGearRack, CycloidGearRack
+from .features import InvoluteGear, CycloidGear, InvoluteGearRack, CycloidGearRack, InternalInvoluteGear
 from pygears.computation import compute_shifted_gears
 
 class ViewProviderGearConnector(object):
@@ -50,7 +50,7 @@ class GearConnector(object):
         obj.addProperty("App::PropertyLink","master_gear","gear","master gear", 1)
         obj.addProperty("App::PropertyLink","slave_gear","gear","slave gear", 1)
         obj.addProperty("App::PropertyAngle", "angle1", "gear", "angle at which second gear is placed", 0)
-        obj.addProperty("App::PropertyAngle", "angle2", "gear", "angle at which second gear is placed", 0)
+        obj.addProperty("App::PropertyAngle", "angle2", "gear", "angle at which second gear is placed", 1)
         obj.version = __version__
         obj.master_gear = master_gear
         obj.slave_gear = slave_gear
@@ -59,9 +59,9 @@ class GearConnector(object):
         obj.Proxy = self
 
     def onChanged(self, fp, prop):
+        # fp.angle2 = fp.master_gear.Placement.Rotation.Angle
         if isinstance(fp.master_gear.Proxy, InvoluteGear) and isinstance(fp.slave_gear.Proxy, InvoluteGear):
-            fp.master_gear.Placement.Rotation.Angle = np.deg2rad(fp.angle2.Value)
-            angle_master = fp.master_gear.Placement.Rotation.Angle
+            angle_master = fp.master_gear.Placement.Rotation.Angle * sum(fp.master_gear.Placement.Rotation.Axis)
             dw_master = fp.master_gear.dw
             dw_slave = fp.slave_gear.dw
             dist = (dw_master + dw_slave) / 2
@@ -88,10 +88,37 @@ class GearConnector(object):
             mat1.move(fp.master_gear.Placement.Base)
             fp.slave_gear.Placement = mat1
 
+        if isinstance(fp.master_gear.Proxy, InternalInvoluteGear) and isinstance(fp.slave_gear.Proxy, InvoluteGear):
+            angle_master = fp.master_gear.Placement.Rotation.Angle * sum(fp.master_gear.Placement.Rotation.Axis)
+            dw_master = fp.master_gear.dw
+            dw_slave = fp.slave_gear.dw
+            dist = (dw_master - dw_slave) / 2
+            if fp.master_gear.shift != 0 or fp.slave_gear.shift != 0:
+                dist, alpha_w = compute_shifted_gears(
+                    fp.master_gear.module,
+                    np.deg2rad(fp.master_gear.pressure_angle.Value),
+                    fp.master_gear.teeth,
+                    fp.slave_gear.teeth,
+                    fp.master_gear.shift,
+                    fp.slave_gear.shift)
+
+            mat0 = FreeCAD.Matrix()  # unity matrix
+            trans = FreeCAD.Vector(dist)
+            mat0.move(trans)
+            rot = FreeCAD.Rotation(FreeCAD.Vector(0,0,1), fp.angle1).toMatrix()
+            angle2 = -dw_master / dw_slave * fp.angle1.Value
+            angle4 = -dw_master / dw_slave * np.rad2deg(angle_master)
+            rot2 = FreeCAD.Rotation(FreeCAD.Vector(0,0,1), angle2).toMatrix()
+            angle3 = abs(fp.slave_gear.teeth % 2 - 1) * 180. / fp.slave_gear.teeth
+            rot3 = FreeCAD.Rotation(FreeCAD.Vector(0,0,1), angle3).toMatrix()
+            rot4 = FreeCAD.Rotation(FreeCAD.Vector(0,0,1), -angle4).toMatrix()
+            mat1 = rot * mat0 * rot2 * rot3 * rot4
+            mat1.move(fp.master_gear.Placement.Base)
+            fp.slave_gear.Placement = mat1
+
         if ((isinstance(fp.master_gear.Proxy, InvoluteGear) and isinstance(fp.slave_gear.Proxy, InvoluteGearRack))
             or (isinstance(fp.master_gear.Proxy, CycloidGear) and isinstance(fp.slave_gear.Proxy, CycloidGearRack))):
-            fp.master_gear.Placement.Rotation.Angle = np.deg2rad(fp.angle2.Value)
-            angle_master = fp.master_gear.Placement.Rotation.Angle
+            angle_master = fp.master_gear.Placement.Rotation.Angle * sum(fp.master_gear.Placement.Rotation.Axis)
             dw_master = fp.master_gear.dw.Value
             dw_slave = 0
             dist = -(dw_master + dw_slave) / 2
@@ -107,8 +134,7 @@ class GearConnector(object):
             fp.slave_gear.Placement = mat3
 
         if isinstance(fp.master_gear.Proxy, CycloidGear) and isinstance(fp.slave_gear.Proxy, CycloidGear):
-            fp.master_gear.Placement.Rotation.Angle = np.deg2rad(fp.angle2.Value)
-            angle_master = fp.master_gear.Placement.Rotation.Angle
+            angle_master = fp.master_gear.Placement.Rotation.Angle * sum(fp.master_gear.Placement.Rotation.Axis)
             dw_master = fp.master_gear.dw
             dw_slave = fp.slave_gear.dw
             dist = (dw_master + dw_slave) / 2