allow zero camera smoothing, more assertions

API change: rename to *SmoothingHalfTimeMillis

viewer/glow-extras/viewer/CameraController.cc

@@ -337,9 +337,17 @@ void CameraController::update(float elapsedSeconds)
     mRight = normalize(cross(mFwd, mUp));
     mUp = normalize(cross(mRight, mFwd));
 
+    TG_ASSERT(s.TranslationalSmoothingHalfTimeMillis >= 0);
+    TG_ASSERT(s.RotationalSmoothingHalfTimeMillis >= 0);
+
     // smoothing
-    auto alphaTranslational = tg::pow(0.5f, 1000 * elapsedSeconds / s.TranslationalSmoothingHalfTime);
-    auto alphaRotational = tg::pow(0.5f, 1000 * elapsedSeconds / s.RotationalSmoothingHalfTime);
+    auto alphaTranslational = 0.f;
+    auto alphaRotational = 0.f;
+    if (s.TranslationalSmoothingHalfTimeMillis > 0)
+        alphaTranslational = tg::pow(0.5f, 1000 * elapsedSeconds / s.TranslationalSmoothingHalfTimeMillis);
+    if (s.RotationalSmoothingHalfTimeMillis > 0)
+        alphaRotational = tg::pow(0.5f, 1000 * elapsedSeconds / s.RotationalSmoothingHalfTimeMillis);
+
     mSmoothedTargetDistance = tg::mix(mTargetDistance, mSmoothedTargetDistance, alphaTranslational);
     mSmoothedTargetPos = mix(mTargetPos, mSmoothedTargetPos, alphaTranslational);
     mSmoothedPos = mix(mPos, mSmoothedPos, alphaTranslational);

viewer/glow-extras/viewer/CameraController.hh

@@ -16,8 +16,8 @@ struct CameraSettings
     tg::angle NumpadRotateDegree = 30_deg;
 
     // smoothing halftimes in ms
-    float TranslationalSmoothingHalfTime = 40;
-    float RotationalSmoothingHalfTime = 30;
+    float TranslationalSmoothingHalfTimeMillis = 40;
+    float RotationalSmoothingHalfTimeMillis = 30;
 
     float FocusRefDistance = 30 * 1000;