Allow the user to hide the ellipsoid drawn by EllipsoidJoint::generateDecorations(). (#3445)

Author: tkuchida

OpenSim/Simulation/SimbodyEngine/EllipsoidJoint.cpp

@@ -82,6 +82,10 @@ void EllipsoidJoint::constructProperties()
     setAuthors("Ajay Seth");
     SimTK::Vec3 radii(NaN);
     constructProperty_radii_x_y_z(radii);
+
+    Appearance appearance;
+    appearance.set_visible(true);
+    constructProperty_Appearance(appearance);
 }
 
 //=============================================================================
@@ -176,6 +180,7 @@ void EllipsoidJoint::generateDecorations
     // since this method is called with fixed={true, false}
     if (!fixed) return; 
     // Construct the visible Ellipsoid
+    if (!get_Appearance().get_visible()) return;
     SimTK::DecorativeEllipsoid ellipsoid(get_radii_x_y_z());
     const OpenSim::PhysicalFrame& frame = getParentFrame();
     ellipsoid.setColor(Vec3(0.0, 1.0, 1.0));

OpenSim/Simulation/SimbodyEngine/EllipsoidJoint.h

@@ -79,6 +79,9 @@ OpenSim_DECLARE_CONCRETE_OBJECT(EllipsoidJoint, Joint);
         Rotation3Z = 2u  ///< 2
     };
 
+    OpenSim_DECLARE_UNNAMED_PROPERTY(Appearance,
+        "Default appearance attributes for this EllipsoidJoint");
+
 private:
     /** Specify the Coordinates of the EllipsoidJoint */
     CoordinateIndex rx{ constructCoordinate(Coordinate::MotionType::Rotational,
@@ -120,6 +123,11 @@ OpenSim_DECLARE_CONCRETE_OBJECT(EllipsoidJoint, Joint);
     //Set properties
     void setEllipsoidRadii(const SimTK::Vec3& radii);
 
+    /** Turn on/off the ellipsoid drawn by generateDecorations(). */
+    void setEllipsoidVisible(bool visible) {
+        upd_Appearance().set_visible(visible);
+    };
+
     /** Exposes getCoordinate() method defined in base class (overloaded below).
         @see Joint */
     using Joint::getCoordinate;