text: /*****************************************************************************************
   *                                                                                       *
   * OpenSpace                                                                             *
   *                                                                                       *
   * Copyright (c) 2014-2018                                                               *
   *                                                                                       *
   * Permission is hereby granted, free of charge, to any person obtaining a copy of this  *
   * software and associated documentation files (the "Software"), to deal in the Software *
   * without restriction, including without limitation the rights to use, copy, modify,    *
   * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to    *
   * permit persons to whom the Software is furnished to do so, subject to the following   *
   * conditions:                                                                           *
   *                                                                                       *
   * The above copyright notice and this permission notice shall be included in all copies *
   * or substantial portions of the Software.                                              *
   *                                                                                       *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,   *
   * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
   * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT    *
   * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF  *
   * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE  *
   * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                                         *
   ****************************************************************************************/
  
  #ifndef __OPENSPACE_CORE___KEYFRAMENAVIGATOR___H__
  #define __OPENSPACE_CORE___KEYFRAMENAVIGATOR___H__
  
  #include <openspace/util/timeline.h>
  #include <openspace/network/messagestructures.h>
  #include <ghoul/glm.h>
  #include <ghoul/misc/boolean.h>
  #include <glm/gtx/quaternion.hpp>
  
  namespace openspace {
      class Camera;
      class TimeManager;
  } // namespace openspace
  
  namespace openspace::interaction {
  
  enum class KeyframeTimeRef {
      Relative_applicationStart,
      Relative_recordedStart,
      Absolute_simTimeJ2000
  };
  
  class KeyframeNavigator {
  public:
      BooleanType(Inclusive);
  
      struct CameraPose {
          glm::dvec3 position;
          glm::quat rotation;
          std::string focusNode;
          float scale;
          bool followFocusNodeRotation;
      };
  
      /**
      * Update camera position using the next camera pose keyframe from the timeline.
      * Returns true if camera was set to a pose from the next keyframe.
      * Returns false if no keyframes are available after the current time.
      * \param camera A reference to the camera object to have its pose updated.
      * \param ignoreFutureKeyframes true if only past keyframes are to be used.
      * \returns true only if a new future keyframe is available to set camera pose.
      */
      bool updateCamera(Camera& camera, bool ignoreFutureKeyframes);
      static bool updateCamera(Camera* camera, const CameraPose prevPose,
          const CameraPose nextPose, double t, bool ignoreFutureKeyframes);
  
      Timeline<CameraPose>& timeline();
      void addKeyframe(double timestamp, KeyframeNavigator::CameraPose pose);
      void removeKeyframesAfter(double timestamp, Inclusive inclusive = Inclusive::No);
      void clearKeyframes();
      size_t nKeyframes() const;
      const std::vector<datamessagestructures::CameraKeyframe>& keyframes() const;
      double currentTime() const;
      void setTimeReferenceMode(KeyframeTimeRef refType, double referenceTimestamp);
  
  private:
      Timeline<CameraPose> _cameraPoseTimeline;
      KeyframeTimeRef _timeframeMode = KeyframeTimeRef::Relative_applicationStart;
      double _referenceTimestamp = 0.0;
  };
  
  } // namespace openspace::interaction
  
  #endif // __OPENSPACE_CORE___KEYFRAMENAVIGATOR___H__
  