Trackball::set_control_mode()

panda/src/tform/trackball.cxx

@@ -57,6 +57,7 @@ Trackball(const string &name) :
   _orig = LMatrix4::ident_mat();
   _invert = true;
   _cs = get_default_coordinate_system();
+  _control_mode = CM_default;
 
   // We want to track the state of these buttons.
   watch_button(MouseButton::one());
@@ -336,6 +337,32 @@ get_invert() const {
   return _invert;
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: Trackball::set_control_mode
+//       Access: Published
+//  Description: Sets the control mode.  Normally this is CM_default,
+//               which means each mouse button serves its normal
+//               function.  When it is CM_truck, CM_pan, CM_dolly, or
+//               CM_roll, all of the mouse buttons serve the indicated
+//               function instead of their normal function.  This can
+//               be used in conjunction with some external way of
+//               changing modes.
+////////////////////////////////////////////////////////////////////
+void Trackball::
+set_control_mode(ControlMode control_mode) {
+  _control_mode = control_mode;
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: Trackball::get_control_mode
+//       Access: Published
+//  Description: Returns the control mode.  See set_control_mode().
+////////////////////////////////////////////////////////////////////
+Trackball::ControlMode Trackball::
+get_control_mode() const {
+  return _control_mode;
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: Trackball::set_rel_to
 //       Access: Published
@@ -446,6 +473,34 @@ apply(double x, double y, int button) {
     // translation to be in those local coordinates.
     reextract();
   }
+
+  if (button == B1_MASK && _control_mode != CM_default) {
+    // We have a control mode set; this may change the meaning of
+    // button 1.  Remap button to match the current control mode
+    // setting.
+    switch (_control_mode) {
+    case CM_truck:
+      button = B1_MASK;
+      break;
+
+    case CM_pan:
+      button = B2_MASK;
+      break;
+
+    case CM_dolly:
+      button = B3_MASK;
+      break;
+
+    case CM_roll:
+      button = B2_MASK | B3_MASK;
+      break;
+
+    case CM_default:
+      // Not possible due to above logic.
+      nassertv(false);
+    }
+  }
+
   if (button == B1_MASK) {
     // Button 1: translate in plane parallel to screen.
 

panda/src/tform/trackball.h

@@ -81,6 +81,17 @@ PUBLISHED:
 
   /// **** Misc ****
 
+  enum ControlMode {
+    CM_default,
+    CM_truck,  // Normally mouse 1
+    CM_pan,    // Normally mouse 2
+    CM_dolly,  // Normally mouse 3
+    CM_roll,   // Normally mouse 2 + 3
+  };
+
+  void set_control_mode(ControlMode control_mode);
+  ControlMode get_control_mode() const;
+
   void set_invert(bool flag);
   bool get_invert() const;
 
@@ -113,6 +124,7 @@ private:
   bool _invert;
   NodePath _rel_to;
   CoordinateSystem _cs;
+  ControlMode _control_mode;
 
 protected:
   // Inherited from DataNode