From f5b9e11841ae07f5d7ef57405bd9882cf6677502 Mon Sep 17 00:00:00 2001
From: gka <gka@opencascade.com>
Date: Mon, 24 Apr 2006 07:43:11 +0000
Subject: [PATCH] Add method for getting tangent on curve by parameter

---
 src/GEOMImpl/GEOMImpl_IBasicOperations.cxx | 49 ++++++++++++++++++++++
 src/GEOMImpl/GEOMImpl_IBasicOperations.hxx |  3 ++
 2 files changed, 52 insertions(+)

diff --git a/src/GEOMImpl/GEOMImpl_IBasicOperations.cxx b/src/GEOMImpl/GEOMImpl_IBasicOperations.cxx
index 9a7ba439c..a29b7f90c 100644
--- a/src/GEOMImpl/GEOMImpl_IBasicOperations.cxx
+++ b/src/GEOMImpl/GEOMImpl_IBasicOperations.cxx
@@ -221,6 +221,55 @@ Handle(GEOM_Object) GEOMImpl_IBasicOperations::MakePointOnCurve
   return aPoint;
 }
 
+//=============================================================================
+/*!
+ *  MakeTangentOnCurve
+ */
+//=============================================================================
+Handle(GEOM_Object) GEOMImpl_IBasicOperations::MakeTangentOnCurve
+                            (const Handle(GEOM_Object)& theCurve, double theParameter)
+{
+  SetErrorCode(KO);
+
+  if (theCurve.IsNull()) return NULL;
+
+  //Add a new Vector object
+  Handle(GEOM_Object) aVec = GetEngine()->AddObject(GetDocID(), GEOM_VECTOR);
+
+  //Add a new Point function for creation a point relativley another point
+  Handle(GEOM_Function) aFunction = aVec->AddFunction(GEOMImpl_VectorDriver::GetID(), VECTOR_TANGENT_CURVE_PAR);
+
+  //Check if the function is set correctly
+  if (aFunction->GetDriverGUID() != GEOMImpl_VectorDriver::GetID()) return NULL;
+
+  GEOMImpl_IVector aVI (aFunction);
+
+  Handle(GEOM_Function) aRefFunction = theCurve->GetLastFunction();
+  if (aRefFunction.IsNull()) return NULL;
+
+  aVI.SetCurve(aRefFunction);
+  aVI.SetParameter(theParameter);
+
+  //Compute the vector value
+  try {
+    if (!GetSolver()->ComputeFunction(aFunction)) {
+      SetErrorCode("Vector driver failed");
+      return NULL;
+    }
+  }
+  catch (Standard_Failure) {
+    Handle(Standard_Failure) aFail = Standard_Failure::Caught();
+    SetErrorCode(aFail->GetMessageString());
+    return NULL;
+  }
+
+  //Make a Python command
+  GEOM::TPythonDump(aFunction) << aVec << " = geompy.MakeTangentOnCurve("
+                               << theCurve << ", " << theParameter << ")";
+
+  SetErrorCode(OK);
+  return aVec;
+}
 
 //=============================================================================
 /*!
diff --git a/src/GEOMImpl/GEOMImpl_IBasicOperations.hxx b/src/GEOMImpl/GEOMImpl_IBasicOperations.hxx
index 7106f4cd9..36aa0afcb 100644
--- a/src/GEOMImpl/GEOMImpl_IBasicOperations.hxx
+++ b/src/GEOMImpl/GEOMImpl_IBasicOperations.hxx
@@ -47,6 +47,9 @@ class GEOMImpl_IBasicOperations : public GEOM_IOperations {
   Standard_EXPORT Handle(GEOM_Object) MakeVectorTwoPnt (Handle(GEOM_Object) thePnt1,
                                         Handle(GEOM_Object) thePnt2);
 
+  Standard_EXPORT Handle(GEOM_Object) MakeTangentOnCurve(const Handle(GEOM_Object)& theCurve, 
+							 double theParameter);
+
   // Line
   Standard_EXPORT Handle(GEOM_Object) MakeLineTwoPnt (Handle(GEOM_Object) thePnt1,
                                       Handle(GEOM_Object) thePnt2);
-- 
2.39.2