Event Recorder

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Event Recorder is a tool for regression testing of game engines. It is used to record gameplays and to play them back after engine updates, to verify that the new engine version works the same. Record and playback processes may be started from the command line or from the GUI.

Command line parameters

--record-mode sets the mode the event recorder will be started with. Possible values are:
	record: begin gameplay recording
	playback: play back gameplay from previously created file
	info: output information about the previously created record file to the console in machine readable format

--record-file-name name of file to record or playback from.

--disable-display disable creation of SDL window and SDL context to screen. In playback mode, output information of playback in machine-readable format to console.

Recorder dialog

It is used to manage record files, start recording and playback. To open the recorder dialog you need to press shift in the launcher to show the alternative menu. After this you need to press the "Record..." button. There is a list of gameplay records in the recorder dialog. After choosing one of them, some information about the record will appear in the right window. It includes the author's name and notes about the record (optionally). There are a few buttons under that list. Their functions:

Edit - shows dialog to change information of selected record (display name, author and record notes)

Delete - remove selected record from filesystem

Cancel - return to launcher

Record - start Event Recorder in recording mode

Playback - start Event Recorder in playback mode

Control window

It is used to control the process of recording or playback and has different functions on these modes. It overlays the game screen and can be dragged.

Playback functions:

Stop: halt playback and return to launcher

Switch to game: halt recording and play in normal mode

Fast forward: remove all delays and play it back as fast as possible

Remark: in playback mode the Event Recorder blocks all user input. To use the control window you should press Ctrl+P to pause the game

Record functions:

Stop: halt recording and return to launcher

Edit notes: change info about the record (display name, author and notes)


  • Manually create screenshots via key binding (useful because the screenshot md5s are validated and you sometimes have a special animation or sprite active which you would like to explicitly validate)
  • Screenshots for 1 byte pixel format are not saved

Known Issues

  • GUI dialogs are not visible during playback/recording.

How to reproduce: Record any game and try to open up the GMM, it will not be visible.

  • Events don't match 100% - maybe due to timing issues. I've seen this while recording a twine playthrough for scene 1 - and the guy that should give the key wasn't hit. The only real reason that I see here is the timing

How to reproduce: No reliable way - but I suppose that it will happen sooner or later in games where game mechanics are based on timing.

  • Events happening while the GUI is open are not recorded.

This is an issue for games which rely on our GUI (like for example Hugo). It will also break automated testing when the GUI was opened while recording (like for example the pause dialog in SCUMM games). The reason here is that you will have to close the GUI manually on playback because the user events leading to closing of the GUI are not recorded.

How to reproduce: Record any game, bring up the GMM and close it by pressing ESC. Stop recording. Play the recording file. You will notice after the GMM is opened the recording will stay paused.

  • Brining up the pause dialog in SCUMM games (like Monkey Island 2) cannot be reliably done.

How to reproduce: Record a SCUMM game (like Monkey Island 2). Press space. You will notice that the pause dialog closes immediately most of the time. (Right now you can check whether the dialog is open by checking whether the record timer in the top left is paused). This does not happen in normal play.

  • Audio callback sometimes not/very slowly called while recording(?)

How to reproduce: Start Monkey Island 1 CD. Watch the whole intro sequence. Return to launcher. Start recording of Monkey Island 1 CD. You will notice that the LucasFilm logo is displayed for a long time.

Further notes: The really oddity here is that when playing the recording everything seems to work and the logo's animation is played at normal timings. This causes the recording and playback to become out of sync (you can notice that because the screenshots taken differ and the recorder warns about it). A recording made by the procedure above can be obtained here (recording was stopped after 42 minutes while the "Part One" screen was visible).

  • Recorder GUI does not work on playback

This behavior is documented but at the very least confusing.

How to reproduce: Play a recording. Try to press a button of the GUI in the top left. It will not work.

  • Recorder GUI hides part of the screen

This is especially annoying in old SCUMM games where the dialog lines are shown at the top of the screen.

How to reproduce: Record/play a recording in for example Indy3. The GUI will make it impossible to read the beginning of the dialog lines.

    • Sev: Recorder dialog could be dragged anywhere on the screen.