0028850: Visualization - Length dimension along Horizontal/Vertical axes

AIS_LengthDimension interface was extended to allow setting a custom dimension direction.
The value of dimension in this case is equal to projection of the distance between dimension attributes(points) to this direction.

vlengthparam command is implemented to set custom length direction in DRAW.

src/ViewerTest/ViewerTest_RelationCommands.cxx

@@ -74,6 +74,7 @@
 #include <TCollection_AsciiString.hxx>
 #include <TCollection_ExtendedString.hxx>
 #include <TColStd_MapOfInteger.hxx>
+#include <TColStd_SequenceOfReal.hxx>
 #include <TopAbs.hxx>
 #include <TopAbs_ShapeEnum.hxx>
 #include <TopExp.hxx>
@@ -348,7 +349,7 @@ static int ParseDimensionParams (Standard_Integer  theArgNum,
     {
       if (anIt + 1 >= theArgNum)
       {
-        std::cout << "Error: wrong number of values for parameter '" << aParam.ToCString() << "'.\n";
+        std::cout << "Error: wrong number of values for parameter '" << aParam << "'.\n";
         return 1;
       }
 
@@ -1622,6 +1623,109 @@ static int VDimParam (Draw_Interpretor& theDi, Standard_Integer theArgNum, const
   return 0;
 }
 
+//=======================================================================
+//function : VLengthParam
+//purpose  : Sets parameters to length dimension.
+//=======================================================================
+static int VLengthParam (Draw_Interpretor&, Standard_Integer theArgNum, const char** theArgVec)
+{
+  if (theArgNum < 3)
+  {
+    std::cout << theArgVec[0] << " error: the wrong number of input parameters.\n";
+    return 1;
+  }
+
+  TCollection_AsciiString aName (theArgVec[1]);
+  if (!GetMapOfAIS().IsBound2 (aName))
+  {
+    std::cout << theArgVec[0] << "error: no object with this name.\n";
+    return 1;
+  }
+
+  Handle(AIS_InteractiveObject) anObject = Handle(AIS_InteractiveObject)::DownCast(GetMapOfAIS().Find2 (aName));
+  if (anObject->Type() != AIS_KOI_Dimension)
+  {
+    std::cout << theArgVec[0] << "error: no dimension with this name.\n";
+    return 1;
+  }
+  
+  Handle(AIS_LengthDimension) aLengthDim = Handle(AIS_LengthDimension)::DownCast (anObject);
+  if (aLengthDim.IsNull())
+  {
+    std::cout << theArgVec[0] << "error: no length dimension with this name.\n";
+    return 1;
+  }
+
+  // parse direction value
+  gp_Dir aDirection;
+  int anArgumentIt = 2;
+  TCollection_AsciiString aParam (theArgVec[anArgumentIt]);
+  aParam.LowerCase();
+
+  bool isCustomDirection = false;
+  if (aParam.IsEqual ("-direction"))
+  {
+    if (anArgumentIt + 1 >= theArgNum)
+    {
+      std::cout << "Error: "<< aParam <<" direction should have value.\n";
+      return 1;
+    }
+    anArgumentIt++;
+    isCustomDirection = Standard_True;
+    TCollection_AsciiString aValue = theArgVec[anArgumentIt];
+    aValue.LowerCase();
+    if (aValue == "ox")
+      aDirection = gp::DX();
+    else if (aValue == "oy")
+      aDirection = gp::DY();
+    else if (aValue == "oz")
+      aDirection = gp::DZ();
+    else if (aValue == "autodirection")
+      isCustomDirection = false;
+    else
+    {
+      if (anArgumentIt + 2 >= theArgNum)
+      {
+        std::cout << "Error: wrong number of values for parameter '" << aParam << "'.\n";
+        return 1;
+      }
+      // access coordinate arguments
+      TColStd_SequenceOfReal aCoords;
+      for (; anArgumentIt < theArgNum; ++anArgumentIt)
+      {
+        TCollection_AsciiString anArg (theArgVec[anArgumentIt]);
+        if (!anArg.IsRealValue())
+        {
+          break;
+        }
+        aCoords.Append (anArg.RealValue());
+      }
+      // non-numeric argument too early
+      if (aCoords.IsEmpty() || aCoords.Size() != 3)
+      {
+        std::cout << "Error: wrong number of direction arguments.\n";
+        return 1;
+      }
+      aDirection = gp_Dir (aCoords.Value (1), aCoords.Value (2), aCoords.Value (3));
+    }
+  }
+
+  aLengthDim->SetDirection (aDirection, isCustomDirection);
+  if (!aLengthDim->IsValid())
+  {
+    std::cout << "Error: Dimension geometry or plane is not valid.\n";
+    return 1;
+  }
+
+  // Redisplay a dimension after parameter changing.
+  if (ViewerTest::GetAISContext()->IsDisplayed (aLengthDim))
+  {
+    ViewerTest::GetAISContext()->Redisplay (aLengthDim, true);
+  }
+
+  return 0;
+}
+
 //=======================================================================
 //function : VAngleParam
 //purpose  : Sets aspect parameters to angle dimension.
@@ -1902,10 +2006,19 @@ void ViewerTest::RelationCommands(Draw_Interpretor& theCommands)
     " -See also: vmovedim, vdimension.\n",
     __FILE__,VDimParam,group);
 
+  theCommands.Add("vlengthparam",
+    "vlengthparam name"
+    "[-direction {ox|oy|oz|x y z|autodirection}]\n"
+    " -Sets parameters for length dimension.\n"
+    " -See also: vdimparam, vdimension.\n",
+    __FILE__,VLengthParam,group);
+
   theCommands.Add("vangleparam",
     "vangleparam name"
     "[-type interior|exterior]\n"
-    "[-showarrow first|second|both|none]\n",
+    "[-showarrow first|second|both|none]\n"
+    " -Sets parameters for angle dimension.\n"
+    " -See also: vdimparam, vdimension.\n",
     __FILE__,VAngleParam,group);
 
   theCommands.Add("vmovedim",