TechDraw: Axo Dimension Fixes (#26445)

* [TD]fix dim text on wrong side of dim line

- this fixes the problem when the dimension line is +/- vertical

* [TD]Avoid use of CosmeticVertex for Axo Dimension

* [TD]fix CI warnings re unused variable

* Update DrawViewPyImp.cpp per review comments.

src/Mod/TechDraw/App/DrawView.pyi

@@ -4,7 +4,7 @@ from __future__ import annotations
 
 from typing import Any
 
-from Base.Metadata import export
+from Base.Metadata import export, constmethod
 
 from App.DocumentObject import DocumentObject
 
@@ -27,10 +27,19 @@ class DrawView(DocumentObject):
         No return value.  Replace the current label with a translated version where possible.
         """
         ...
-
+    @constmethod
     def getScale(self) -> Any:
         """
         float scale = getScale().  Returns the correct scale for this view.  Handles whether to
         use this view's scale property or a parent's view (as in a projection group).
         """
         ...
+
+    @constmethod
+    def findParentPage(self) -> Any:
+        """
+        DrawPage parent = findParentPage().  Returns the parent page that contains this view.
+        """
+        ...
+
+

src/Mod/TechDraw/App/DrawViewPyImp.cpp

@@ -25,6 +25,7 @@
 // inclusion of the generated files (generated out of DrawViewPy.xml)
 #include <Mod/TechDraw/App/DrawViewPy.h>
 #include <Mod/TechDraw/App/DrawViewPy.cpp>
+#include <Mod/TechDraw/App/DrawPagePy.h>
 
 using namespace TechDraw;
 
@@ -78,7 +79,7 @@ PyObject* DrawViewPy::translateLabel(PyObject *args)
 }
 
 //! return the correct scale for this view
-PyObject* DrawViewPy::getScale(PyObject *args)
+PyObject* DrawViewPy::getScale(PyObject *args) const
 {
     if (!PyArg_ParseTuple(args, "")) {
             throw Py::TypeError("Do not understand passed parameter.");
@@ -89,6 +90,18 @@ PyObject* DrawViewPy::getScale(PyObject *args)
     return PyFloat_FromDouble(dv->getScale());
 }
 
+//! return the correct scale for this view
+PyObject* DrawViewPy::findParentPage(PyObject *args) const
+{
+    if (!PyArg_ParseTuple(args, "")) {
+            throw Py::TypeError("Do not understand passed parameter.");
+    }
+
+    DrawView* dv = getDrawViewPtr();
+    DrawPage* parent = dv->findParentPage();
+
+    return Py::new_reference_to(parent->getPyObject());
+}
 
 
 PyObject *DrawViewPy::getCustomAttributes(const char* /*attr*/) const

src/Mod/TechDraw/TechDrawTools/CommandAxoLengthDimension.py

@@ -38,7 +38,24 @@ import FreeCADGui as Gui
 import TechDrawTools.TDToolsUtil as Utils
 
 import TechDraw
-from math import degrees
+import math
+
+# A hack to deal with garbage in the low bits causing wrong decisions. dimensionLineAngle is in radians.  If 
+# dimensionLineAngle is 90deg +/- AngularTolerance, we treat it as a vertical dimension line.  This affects which
+# side of the dimension line is used for the dimension text.
+def makePlumb(dimensionLineAngle):
+    HalfPi = math.pi / 2.0
+    
+    AngularTolerance = 0.01   # This value is a guess.  It works for the file in issue #16172, but
+                              # seems small (~0.5deg).  
+
+    if math.isclose(dimensionLineAngle, HalfPi, abs_tol=AngularTolerance):
+        return HalfPi
+    elif math.isclose(dimensionLineAngle, -HalfPi, abs_tol=AngularTolerance):
+        return -HalfPie
+ 
+    return dimensionLineAngle
+    
 
 class CommandAxoLengthDimension:
     """Creates a 3D length dimension."""
@@ -68,33 +85,57 @@ class CommandAxoLengthDimension:
         edges = Utils.getSelEdges(2)
         vertexes = Utils.getSelVertexes(0)
 
+        vertNames = list()
+        edgeNames = list()
         if len(vertexes)<2:
             vertexes.append(edges[0].Vertexes[0])
             vertexes.append(edges[0].Vertexes[1])
+            edgeNames = Utils.getSelEdgeNames(2)
+        else:
+            vertNames = Utils.getSelVertexNames(2)
 
         view = Utils.getSelView()
+        page = view.findParentPage()
         scale = view.getScale()
 
         StartPt, EndPt = edges[1].Vertexes[0].Point, edges[1].Vertexes[1].Point
         extLineVec = EndPt.sub(StartPt)
         StartPt, EndPt = edges[0].Vertexes[0].Point, edges[0].Vertexes[1].Point
         dimLineVec = EndPt.sub(StartPt)
+
         xAxis = App.Vector(1,0,0)
-        extAngle = degrees(extLineVec.getAngle(xAxis))
-        lineAngle = degrees(dimLineVec.getAngle(xAxis))
+        extAngle = math.degrees(extLineVec.getAngle(xAxis))
+        lineAngle = math.degrees(makePlumb(dimLineVec.getAngle(xAxis)))
 
         if extLineVec.y < 0.0:
             extAngle = 180-extAngle
         if dimLineVec.y < 0.0:
             lineAngle = 180-lineAngle
+
         if abs(extAngle-lineAngle)>0.1:
-            distanceDim=TechDraw.makeDistanceDim(view,'Distance',vertexes[0].Point*scale,vertexes[1].Point*scale)
+            # re issue: https://github.com/FreeCAD/FreeCAD/issues/13677
+            # Instead of using makeDistanceDim (which is meant for extent dimensions), we use the 
+            # same steps as in CommandCreateDims.cpp to create a regular length dimension.  This avoids
+            # the creation of CosmeticVertex objects to serve as dimension points.  These CosmeticVertex
+            # objects are never deleted, but are no longer used once their dimension is deleted. 
+            # distanceDim=TechDraw.makeDistanceDim(view,'Distance',vertexes[0].Point*scale,vertexes[1].Point*scale)
+            distanceDim = view.Document.addObject("TechDraw::DrawViewDimension", "Dimension")
+            distanceDim.Type = "Distance"
+            distanceDim.MeasureType = "Projected"       #should this not be True?
+            self.setReferences(distanceDim, view, edgeNames, vertNames)
+            page.addView(distanceDim)
+
             distanceDim.AngleOverride = True
             distanceDim.LineAngle = lineAngle
             distanceDim.ExtensionAngle = extAngle
-            distanceDim.X = scale*(vertexes[0].Point.x+vertexes[1].Point.x)/2
-            distanceDim.Y = scale*(vertexes[0].Point.y+vertexes[1].Point.y)/2
-            distanceDim.recompute()
+
+            distanceDim.recompute()     # ensure linearPoints has been set
+
+            # as in CmdCreateDims::positionDimText:
+            linearPoints = distanceDim.getLinearPoints()
+            mid = (linearPoints[0] + linearPoints[1]) / 2
+            distanceDim.X = mid.x
+            distanceDim.Y = -mid.y
 
             (px,py,pz) = Utils.getCoordinateVectors(view)
             arrowTips = distanceDim.getArrowPositions()
@@ -114,8 +155,10 @@ class CommandAxoLengthDimension:
 
             distanceDim.recompute()
             view.requestPaint()
+
         Gui.Selection.clearSelection()
         App.closeActiveTransaction()
+        view.touch()	# make view claim its new child
 
     def IsActive(self):
         """Return True when the command should be active or False when it should be disabled (greyed)."""
@@ -146,6 +189,16 @@ class CommandAxoLengthDimension:
         else:
             return formatSpec.format(value)
 
+    def setReferences(self, dimension, view, edgeNameList, vertexNameList):
+        references = list()
+        if vertexNameList:
+            for vert in vertexNameList:
+                references.append((view, vert))
+        else:
+            references.append((view, edgeNameList[0]))
+
+        dimension.References2D = references
+
 #
 # The command must be "registered" with a unique name by calling its class.
 Gui.addCommand('TechDraw_AxoLengthDimension', CommandAxoLengthDimension())

src/Mod/TechDraw/TechDrawTools/TDToolsUtil.py

@@ -155,3 +155,68 @@ def getCoordinateVectors(view):
     py = wire2D.Edges[1].Vertexes[0].Point
     pz = wire2D.Edges[2].Vertexes[0].Point
     return (px,py,pz)
+    
+
+# +/- the same as getSelVertexes, but returns the vertex name instead of the vertex object.
+def getSelVertexNames(nVertex=1, nSel=0):
+    '''
+    vertexNames = getSelVertexNames(nVertex)
+    nVertex=1 ... min. number of selected vertexes
+    nSel=0 ... number of selected view, 0 = first selected
+    Return a list of the names of the selected vertexes if at least nVertex vertexes are selected, otherwise return False
+    '''
+    view = getSelView(nSel)
+    if not view:
+        return False
+        
+    if not Gui.Selection.getSelectionEx():
+        displayMessage('TechDraw_Utils',
+                        QT_TRANSLATE_NOOP('TechDraw_Utils','No vertex selected'))
+        return False
+    objectList = Gui.Selection.getSelectionEx()[nSel].SubElementNames
+
+    vertexNames = []
+    for objectString in objectList:
+        if objectString[0:6] == 'Vertex':
+            vertexNames.append(objectString)
+
+    if (len(vertexNames) < nVertex):
+        displayMessage('TechDraw_Utils',
+                        QT_TRANSLATE_NOOP('TechDraw_Utils','Select at least ')+
+                        str(nVertex)+
+                        QT_TRANSLATE_NOOP('TechDraw_Utils',' vertexes'))
+        return False
+
+    return vertexNames
+
+# +/- the same as getSelEdges, but returns the edge name instead of the vertex object.
+def getSelEdgeNames(nEdge=1, nSel=0):
+    '''
+    edges = getSelEdgeNames(nEdge)
+    nEdge=1 ... min. number of selected edges
+    nSel=0 ... number of selected view, 0 = first selected
+    Return a list of names for selected edges if at least nedge edges are selected, otherwise return False
+    '''
+    view = getSelView(nSel)
+    if not view:
+        return False
+        
+    if not Gui.Selection.getSelectionEx():
+        displayMessage('TechDraw_Utils',
+                        QT_TRANSLATE_NOOP('TechDraw_Utils','No edge selected'))
+        return False
+    objectList = Gui.Selection.getSelectionEx()[nSel].SubElementNames
+
+    edgeNames = []
+    for objectString in objectList:
+        if objectString[0:4] == 'Edge':
+            edgeNames.append(objectString)
+
+    if (len(edgeNames) < nEdge):
+        displayMessage('TechDraw_Utils',
+                        QT_TRANSLATE_NOOP('TechDraw_Utils','Select at least ')+
+                        str(nEdge)+
+                        QT_TRANSLATE_NOOP('TechDraw_Utils',' edges'))
+        return False
+    else:
+        return edgeNames