Added test for vtkTextActor picking

This test fails with the OpenGL 2 backend enabled, but passes with the
OpenGL backend.

Rendering/Core/Testing/Cxx/CMakeLists.txt

@@ -55,6 +55,7 @@ vtk_add_test_cxx(${vtk-module}CxxTests tests
   TestOrderedTriangulator.cxx
   TestOpacity.cxx
   TestOSConeCxx.cxx
+  TestPickTextActor.cxx,NO_VALID
   TestPointSelection.cxx,NO_VALID
   TestPolygonSelection.cxx
   TestResetCameraVerticalAspectRatio.cxx

Rendering/Core/Testing/Cxx/TestPickTextActor.cxx

+/*=========================================================================
+
+  Program:   Visualization Toolkit
+  Module:    TestPickTextActor.cxx
+
+  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
+  All rights reserved.
+  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
+
+     This software is distributed WITHOUT ANY WARRANTY; without even
+     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+     PURPOSE.  See the above copyright notice for more information.
+
+=========================================================================*/
+// This tests picking of text actors.
+//
+#include "vtkActor2D.h"
+#include "vtkNew.h"
+#include "vtkPropPicker.h"
+#include "vtkRenderer.h"
+#include "vtkRenderWindow.h"
+#include "vtkRenderWindowInteractor.h"
+#include "vtkTextActor.h"
+
+#include <cstdlib>
+
+int TestPickTextActor(int, char*[])
+{
+  vtkNew<vtkTextActor> actor1;
+  actor1->SetInput("One");
+  actor1->SetPosition(140, 140);
+
+  vtkNew<vtkTextActor> actor2;
+  actor2->SetInput("Two");
+  actor2->SetPosition(160, 170);
+
+  vtkNew<vtkRenderer> renderer;
+  renderer->AddActor(actor1.Get());
+  renderer->AddActor(actor2.Get());
+
+  vtkNew<vtkRenderWindow> renWin;
+  renWin->AddRenderer(renderer.Get());
+  renWin->Render();
+
+  vtkNew<vtkPropPicker> picker;
+  picker->Pick(145, 145, 0.0, renderer.Get());
+  vtkActor2D* pickedActor = picker->GetActor2D();
+  if (pickedActor != actor1.Get())
+    {
+    std::cout << "Incorrect actor picked!" << std::endl;
+    std::cout << "Should have been " << actor1.Get() << ", but was " << pickedActor << std::endl;
+    return EXIT_FAILURE;
+    }
+
+  return EXIT_SUCCESS;
+}