add view center getter

Author: nmwsharp

include/polyscope/view.h

@@ -101,6 +101,7 @@ glm::mat4 computeHomeView();
 void resetCameraToHomeView();
 void flyToHomeView();
 void setViewCenter(glm::vec3 newCenter, bool flyTo = false);
+glm::vec3 getViewCenter();
 
 // These both set the new value, and project the current view as-needed to conform to the new setting
 void updateViewAndChangeNavigationStyle(NavigateStyle newStyle, bool flyTo = false);

src/view.cpp

@@ -561,6 +561,8 @@ void updateViewAndChangeCenter(glm::vec3 newCenter, bool flyTo) {
 
 void setViewCenter(glm::vec3 newCenter, bool flyTo) { updateViewAndChangeCenter(newCenter, flyTo); }
 
+glm::vec3 getViewCenter() { return view::viewCenter; }
+
 void lookAt(glm::vec3 cameraLocation, glm::vec3 target, bool flyTo) {
   lookAt(cameraLocation, target, getUpVec(), flyTo);
 }