Fixed arcball issuses. Reverted last commit

Author: Tark Patel

src/Externals/spire/arc-ball/ArcBall.cpp

@@ -101,7 +101,7 @@ glm::quat ArcBall::quatFromUnitSphere(const glm::vec3& from, const glm::vec3& to
   //TODO: check if cross is 0 before normalize. Crashes on Windows
   auto c = glm::cross(from, to);
   if (c == glm::vec3(0, 0, 0))
-    return {};
+    return glm::quat(1.0, 0.0, 0.0, 0.0);
 
   glm::vec3 axis = glm::normalize(c);
 

src/Interface/Modules/Render/ES/SRCamera.cc

@@ -205,13 +205,9 @@ namespace SCIRun {
     //----------------------------------------------------------------------------------------------
     void SRCamera::tryAutoRotate()
     {
-      const static double epsilon = 0.02e-12;
-      if (glm::length(autoRotateVec) > epsilon)
-      {
-        mArcLookAt->doReferenceDown(lastMousePos);
-        mArcLookAt->doRotation(lastMousePos + autoRotateVec);
-        setClippingPlanes();
-      }
+      mArcLookAt->doReferenceDown(lastMousePos);
+      mArcLookAt->doRotation(lastMousePos + autoRotateVec);
+      setClippingPlanes();
     }
 
     //----------------------------------------------------------------------------------------------