From ce9f4f199a4b4df7045a65460dfbb508a06a4644 Mon Sep 17 00:00:00 2001
From: WandererFan <wandererfan@gmail.com>
Date: Sat, 15 Oct 2016 19:50:42 -0400
Subject: [PATCH] Fix XAxis orientation Remove need for XAxisDirection property

---
 src/Mod/TechDraw/App/DrawUtil.cpp       |  4 ++++
 src/Mod/TechDraw/App/DrawUtil.h         |  1 +
 src/Mod/TechDraw/App/GeometryObject.cpp | 24 ++++++++++++++++--------
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/src/Mod/TechDraw/App/DrawUtil.cpp b/src/Mod/TechDraw/App/DrawUtil.cpp
index 4b322e0f1..25a44dd47 100644
--- a/src/Mod/TechDraw/App/DrawUtil.cpp
+++ b/src/Mod/TechDraw/App/DrawUtil.cpp
@@ -197,4 +197,8 @@ void DrawUtil::dumpEdge(char* label, int i, TopoDS_Edge e)
     Base::Console().Message("%s edge:%d start:(%.3f,%.3f,%.3f)  end:(%.2f,%.3f,%.3f)\n",label,i,
                             vStart.X(),vStart.Y(),vStart.Z(),vEnd.X(),vEnd.Y(),vEnd.Z());
 }
+const char* DrawUtil::printBool(bool b)
+{
+    return (b ? "True" : "False");
+}
 //==================================
diff --git a/src/Mod/TechDraw/App/DrawUtil.h b/src/Mod/TechDraw/App/DrawUtil.h
index e163426d8..42484925e 100644
--- a/src/Mod/TechDraw/App/DrawUtil.h
+++ b/src/Mod/TechDraw/App/DrawUtil.h
@@ -49,6 +49,7 @@ class TechDrawExport DrawUtil {
         static void countFaces(const char* label, const TopoDS_Shape& s);
         static void countWires(const char* label, const TopoDS_Shape& s);
         static void countEdges(const char* label, const TopoDS_Shape& s);
+        static const char* printBool(bool b);
 };
 
 } //end namespace TechDraw
diff --git a/src/Mod/TechDraw/App/GeometryObject.cpp b/src/Mod/TechDraw/App/GeometryObject.cpp
index 76b5b1662..752dcd650 100644
--- a/src/Mod/TechDraw/App/GeometryObject.cpp
+++ b/src/Mod/TechDraw/App/GeometryObject.cpp
@@ -80,8 +80,6 @@ struct EdgePoints {
     TopoDS_Edge edge;
 };
 
-//debugging routine signatures
-const char* _printBool(bool b);
 
 GeometryObject::GeometryObject(DrawViewPart* parent) :
     Tolerance(0.05f),
@@ -166,6 +164,18 @@ void GeometryObject::projectShape(const TopoDS_Shape& input,
                              const Base::Vector3d& direction,
                              const Base::Vector3d& xAxis)
 {
+    Base::Vector3d stdZ(0.0,0.0,1.0);
+    Base::Vector3d flipDirection(direction.x,-direction.y,direction.z);
+    Base::Vector3d cross = flipDirection;
+    //special cases
+    if (flipDirection == stdZ) {
+        cross = Base::Vector3d(1.0,0.0,0.0);
+    } else if (flipDirection == (stdZ * -1.0)) {
+        cross = Base::Vector3d(1.0,0.0,0.0);
+    } else {
+        cross.Normalize();
+        cross = cross.Cross(stdZ);
+    }
     // Clear previous Geometry
     clear();
 
@@ -176,12 +186,11 @@ void GeometryObject::projectShape(const TopoDS_Shape& input,
         brep_hlr = new HLRBRep_Algo();
         brep_hlr->Add(input, m_isoCount);
 
-        // Project the shape into view space with the object's centroid
-        // at the origin.
         gp_Ax2 viewAxis;
         viewAxis = gp_Ax2(inputCenter,
-                          gp_Dir(direction.x, direction.y, direction.z),
-                          gp_Dir(xAxis.x, xAxis.y, xAxis.z));
+                          gp_Dir(flipDirection.x, flipDirection.y, flipDirection.z),
+//                          gp_Dir(xAxis.x, -xAxis.y, xAxis.z));
+                          gp_Dir(cross.x, cross.y, cross.z));
         HLRAlgo_Projector projector( viewAxis );
         brep_hlr->Projector(projector);
         brep_hlr->Update();
@@ -687,7 +696,7 @@ gp_Pnt TechDrawGeometry::findCentroid(const TopoDS_Shape &shape,
     gp_Ax2 viewAxis;
     viewAxis = gp_Ax2(gp_Pnt(0, 0, 0),
                       gp_Dir(direction.x, -direction.y, direction.z),
-                      gp_Dir(xAxis.x, -xAxis.y, xAxis.z)); // Y invert warning!
+                      gp_Dir(xAxis.x, -xAxis.y, xAxis.z));
 
     gp_Trsf tempTransform;
     tempTransform.SetTransformation(viewAxis);
@@ -719,7 +728,6 @@ TopoDS_Shape TechDrawGeometry::mirrorShape(const TopoDS_Shape &input,
     try {
         // Make tempTransform scale the object around it's centre point and
         // mirror about the Y axis
-        // TODO: is this really always Y axis? sb whatever is vertical direction in projection?
         gp_Trsf tempTransform;
         tempTransform.SetScale(inputCenter, scale);
         gp_Trsf mirrorTransform;