Recording and playing camera paths

Gaia Sky offers the possibility to record camera paths out of the box in real time and later play them. These camera paths go to a text file in the temp folder of your system.

Camera path file format

The format of the file is pretty straightforward. It consists of a csv file with white spaces as delimiters, each row containing the state of the camera and the time. The state of the camera consists of 9 double-precision floating point numbers, 3 for the position and 3 for the direction vector and 3 for the up vector.

The reference system used is explained in the Internal reference system section. The units are 1*10^{-9} m.

The format of each row is as follows:

  • long - Time as defined by the getTime() function of java.util.Date (here).
  • double x3 - Position of the camera.
  • double x3 - Direction vector of the camera.
  • double x3 - Up vector of the camera.

Recording camera paths

In order to start recording the camera path, click on the rec-icon-gray REC button next to the Camera section title in the GUI Controls window. The REC button will turn red rec-icon-red, which indicates the camera is being recorded.

In order to stop the recording and write the file, click again on the red REC button. The button will turn grey and a notification will pop up indicating the location of the camera file. Camera files are by default saved in the $HOME/.gaiasky/camera directory.

Playing camera paths

In order to play a camera file, click on the play-icon PLAY icon next to the REC icon. This will prompt a list of available camera files in the $HOME/.gaiasky/camera folder.

You can also combine the camera file playback with the frame output system to save each frame to a JPEG image during playback. To do so, enable the Activate frame output automatically checkbox in the preferences dialog as described in the Camera recording section.