Review and travis fixes

Author: wonder-sk

src/3d/qgscameracontroller.h

@@ -72,10 +72,32 @@ class _3D_EXPORT QgsCameraController : public Qt3DCore::QEntity
     //! Sets the point toward which the camera is looking - this is used when world origin changes (e.g. after terrain generator changes)
     void setLookingAtPoint( const QgsVector3D &point, float distance = -1 );
 
+    /**
+     * Sets the complete camera configuration: the point towards it is looking (in 3D world coordinates), the distance
+     * of the camera from the point, pitch angle in degrees (0 = looking from the top, 90 = looking from the side) and
+     * yaw angle in degrees.
+     * \since QGIS 3.4
+     */
     void setLookingAtPoint( const QgsVector3D &point, float distance, float pitch, float yaw );
 
+    /**
+     * Returns distance of the camera from the point it is looking at.
+     * \since QGIS 3.4
+     */
     float distance() const { return mCameraData.dist; }
+
+    /**
+     * Returns pitch angle in degrees (0 = looking from the top, 90 = looking from the side).
+     * The angle should range from 0 to 180.
+     * \since QGIS 3.4
+     */
     float pitch() const { return mCameraData.pitch; }
+
+    /**
+     * Returns yaw angle in degrees.  Yaw value of zero means the camera is pointing towards north.
+     * The angle should range from 0 to 360.
+     * \since QGIS 3.4
+     */
     float yaw() const { return mCameraData.yaw; }
 
     //! Writes camera configuration to the given DOM element

src/app/3d/qgs3danimationsettings.h

@@ -36,17 +36,18 @@ class Qgs3DAnimationSettings
     //! keyframe definition
     struct Keyframe
     {
-      float time;            //!< Relative time of the keyframe in seconds
-
-      QgsVector3D point;  //!< Point towards which the camera is looking in 3D world coords
-      float dist;   //!< Distance of the camera from the focal point
-      float pitch;  //!< Tilt of the camera in degrees (0 = looking from the top, 90 = looking from the side, 180 = looking from the bottom)
-      float yaw;    //!< Horizontal rotation around the focal point in degrees
+      float time = 0;    //!< Relative time of the keyframe in seconds
+      QgsVector3D point; //!< Point towards which the camera is looking in 3D world coords
+      float dist = 0;    //!< Distance of the camera from the focal point
+      float pitch = 0;   //!< Tilt of the camera in degrees (0 = looking from the top, 90 = looking from the side, 180 = looking from the bottom)
+      float yaw = 0;     //!< Horizontal rotation around the focal point in degrees
     };
 
     typedef QVector<Keyframe> Keyframes;
 
+    //! Configures keyframes of the animation. It is expected that the keyframes are ordered according to their time.
     void setKeyframes( const Keyframes &keyframes ) { mKeyframes = keyframes; }
+    //! Returns keyframes of the animation
     Keyframes keyFrames() const { return mKeyframes; }
 
     //! Returns duration of the whole animation in seconds