ENH:Added nifty translation mode

Graphics/vtkCursor3D.cxx

@@ -20,7 +20,7 @@
 
 #include <math.h>
 
-vtkCxxRevisionMacro(vtkCursor3D, "1.37");
+vtkCxxRevisionMacro(vtkCursor3D, "1.38");
 vtkStandardNewMacro(vtkCursor3D);
 
 // Construct with model bounds = (-1,1,-1,1,-1,1), focal point = (0,0,0),
@@ -53,6 +53,7 @@ vtkCursor3D::vtkCursor3D()
   this->YShadows = 1;
   this->ZShadows = 1;
   this->Wrap = 0;
+  this->TranslationMode = 0;
 }
 
 vtkCursor3D::~vtkCursor3D()
@@ -388,8 +389,9 @@ void vtkCursor3D::Execute()
 }
 
 // Set the boundary of the 3D cursor.
-void vtkCursor3D::SetModelBounds(float xmin, float xmax, float ymin, float ymax,
-                                float zmin, float zmax)
+void vtkCursor3D::SetModelBounds(float xmin, float xmax, 
+                                 float ymin, float ymax,
+                                 float zmin, float zmax)
 {
   if ( xmin != this->ModelBounds[0] || xmax != this->ModelBounds[1] ||
   ymin != this->ModelBounds[2] || ymax != this->ModelBounds[3] ||
@@ -411,6 +413,47 @@ void vtkCursor3D::SetModelBounds(float xmin, float xmax, float ymin, float ymax,
     }
 }
 
+void vtkCursor3D::SetFocalPoint(float x[3])
+{
+  if ( x[0] == this->FocalPoint[0] && x[1] == this->FocalPoint[1] && 
+       x[2] == this->FocalPoint[2] )
+    {
+    return;
+    }
+  
+  this->Modified();
+
+  float v[3];
+  for (int i=0; i<3; i++)
+    {
+    v[i] = x[i] - this->FocalPoint[i];
+    this->FocalPoint[i] = x[i];
+  
+    if ( this->TranslationMode )
+      {
+      this->ModelBounds[2*i] += v[i];
+      this->ModelBounds[2*i+1] += v[i];
+      }
+    else if ( this->Wrap ) //wrap
+      {
+      this->FocalPoint[i] = this->ModelBounds[2*i] + 
+             fmod((double)(this->FocalPoint[i]-this->ModelBounds[2*i]), 
+                  (double)(this->ModelBounds[2*i+1]-this->ModelBounds[2*i]));
+      }
+    else //clamp
+      {
+      if ( x[i] < this->ModelBounds[2*i] ) 
+        { 
+        this->FocalPoint[i] = this->ModelBounds[2*i];
+        }
+      if ( x[i] > this->ModelBounds[2*i+1] ) 
+        { 
+        this->FocalPoint[i] = this->ModelBounds[2*i+1];
+        }
+      }
+    }
+}
+
 void vtkCursor3D::SetModelBounds(float bounds[6])
 {
   this->SetModelBounds(bounds[0], bounds[1], bounds[2], bounds[3], bounds[4],
@@ -456,4 +499,6 @@ void vtkCursor3D::PrintSelf(ostream& os, vtkIndent indent)
   os << indent << "YShadows: " << (this->YShadows ? "On\n" : "Off\n");
   os << indent << "ZShadows: " << (this->ZShadows ? "On\n" : "Off\n");
   os << indent << "Wrap: " << (this->Wrap ? "On\n" : "Off\n");
+  os << indent << "Translation Mode: " 
+     << (this->TranslationMode ? "On\n" : "Off\n");
 }

Graphics/vtkCursor3D.h

@@ -51,8 +51,17 @@ public:
   vtkGetVectorMacro(ModelBounds,float,6);
 
   // Description:
-  // Specify the position of cursor focus.
-  vtkSetVector3Macro(FocalPoint,float);
+  // Specify the position of cursor focus. If translation mode is on,
+  // then the entire cursor (including bounding box, cursor, and shadows)
+  // is translated. Otherwise, the focal point will either be clamped to the
+  // bounding box, or wrapped, if Wrap is on.
+  void SetFocalPoint(float x[3]);
+  void SetFocalPoint(float x, float y, float z)
+    {
+      float xyz[3];
+      xyz[0] = x; xyz[1] = y; xyz[2] = z;
+      this->SetFocalPoint(xyz);
+    }
   vtkGetVectorMacro(FocalPoint,float,3);
 
   // Description:
@@ -85,6 +94,14 @@ public:
   vtkGetMacro(ZShadows,int);
   vtkBooleanMacro(ZShadows,int);
 
+  // Description:
+  // Enable/disable the translation mode. If on, changes in cursor position
+  // cause the entire widget to translate along with the cursor.
+  // By default, translation mode is off.
+  vtkSetMacro(TranslationMode,int);
+  vtkGetMacro(TranslationMode,int);
+  vtkBooleanMacro(TranslationMode,int);
+
   // Description:
   // Turn on/off cursor wrapping. If the cursor focus moves outside the
   // specified bounds, the cursor will either be restrained against the
@@ -116,7 +133,9 @@ protected:
   int XShadows;
   int YShadows;
   int ZShadows;
+  int TranslationMode;
   int Wrap;
+  
 private:
   vtkCursor3D(const vtkCursor3D&);  // Not implemented.
   void operator=(const vtkCursor3D&);  // Not implemented.