v0.01
08-12-2006


-----===== ELD Language Commands and Arguments =====-----

The Edo LaserDisc program uses a scripting language of sorts to execute commands to play the games. Those who have experience in official programming languages (such as Visual Basic, Pascal, C, JAVA) will simply have to adapt to some of the commands. Those who are not familiar with programming languages may have a hard time with creating games. Sorry.

As for movie files, use the "mpeg" format of video files. Even though the internal object for displaying movies in this program is based on Windows Media Player, mpeg file should be used. During the course of creating this program .avi and .wmv files were tested, with failing results. If you truly wish to use such files when making a game, be my guest; however, I can not and will not make an guarantees to the success.


.....::::: Initialization File Commands :::::.....

The initialization file contains many of the basic definitions for the game. For example, the name of the game, author, starting lives, number of continues, and so on.

The initialization file can have any name, but the extension must be .ELD .

  aardvark.eld
  
The following commands are recognized only within the initialization file. If entered into scene files, they will have no effect.

  • game_name game name

    Declares the name of the game within the program.
      game_name Aardvark's Lair II: Time Slip
      

  • author author's name

    Declares the name of the author within the game.
      author John Doe
      

  • version version number

    Declares the version of the game.
      version 1.09
      

  • lives number of starting lives

    Declares the number of lives that the player starts with in the game. The number must be an integer.
      lives 5
      
    Without entering this command, the system automatically defaults to 3 lives.

  • continues number of continues

    Declares the number of times that the player can continue within the game.
      continues 3
      
    Without entering this command, the system automatically defaults to 'unlimited' (9999) continues.

  • attract_file _movie filename_ _starting time of the event_ _ending time of the event_

    Declares the name of the movie file that is played in attract mode.
      attract_file aardvark_intro.mpg 10.0 30.0
      
    If this command is not declared, a generic title will be displayed, with the name of the game.

  • ending_file _movie filename_ _starting time of the event_ _ending time of the event_

    Declares the name of the movie file that is played when the player finishes the game.
      ending_file aardvark_ending.mpg 20.0 40.0
      
    This command is not required. If not declared, no ending will be played when the player completes the last scene; it will simply proceed back to the title of the game.

  • credits_file _movie filename_ _starting time of the event_ _ending time of the event_

    Declares the name of the movie file that is played when the player finishes the game, after the ending movie is played.
      credits_file aardvark_credits.mpg 80.0 90.0
      
    This command is not required. If not declared, nothing will displayed, and will simply proceed back to the title of the game.

  • scene scene filename

    Declares a scene within the game. This command can have multiple instance, creating a scene list.
      scene aardvark1.scn
      scene aardvark2.scn
      scene aardvark3.scn
      
    The game will play the scenes in the order they are declared in this file.

  • scene_rand _start scene number_ _end scene number_

    Declares a block of scenes to be shuffled randomly during play. The "start scene number" and "end scene number" declares the number of the scenes in the scene list. All scenes in the specified range will be shuffled whenever the game is started. For example:
      scene aardvark1.scn
      scene aardvark2.scn
      scene aardvark3.scn
      scene aardvark4.scn
      scene aardvark5.scn
      scene aardvark6.scn
      scene_rand 2 5
      
    In the previous example, scene "aardvark1.scn" will be always be played first, "aardvark2.scn" through "aardvark5.scn" will be played in random order, and "aardvark6.scn" will always be played last.

    Use this command AFTER all "scene" commands, or this command will have no effect. This command is not required.

    The next section contains the commands for scene files. However, a little explanation for "actions" should be given. "Actions" are entries that the player makes during the game. There are a number of actions that can be done, with a single character representation of the action.

    There are a total of nine buttons that you can use for actions. Not that you should need more than nine... At the current time, diagonal actions are not supported. Sorry.


    .....::::: Scene File Commands :::::.....

    Scene files are the main "core" of the game, displaying the movie and tracking commands for the player. While the scene files can have any extension, for convention's sake, use the extension .SCN .

  • videofile movie filename

    This is the video that will be played during the current scene.
      videofile aardvark1.mpg
      

  • starttime starting time of the scene

    When the scene starts, this is the time frame that the scene will start on. This number is the "seconds" time frame of the video. The number is a "double" number (i.e. decimal), so that you can break it down into fractions of seconds for pinpoint accuracy.
      starttime 0.0
      

  • endtime ending time of the scene

    This is the point at which the scene ends. Once the player reaches this point in the video, the scene ends, and will automatically proceed to the next scene. This number is the "seconds" time frame of the video. The number is a "double" number (i.e. decimal), so that you can break it down into fractions of seconds for pinpoint accuracy.
      endtime 160.0
      

  • event _starting time of the event_ _ending time of the event_ [hint hint display]

    Events are what compose the interaction of the player in the scene. In essence, this is where a player enters an action. The numbers are the "seconds" time frame of the video. The numbers are a "double" number (i.e. decimal), so that you can break them down into fractions of seconds for pinpoint accuracy. To "close off" this block, use the "end_event" command.
      event 8.0 11.0
            .....
      end_event
      
    The "hint" argument displays a hint for the player at the bottom of the screen during an event. A one-word argument follows the hint declaration. Entering two words or more are redundant, as the system will only display the first word.
      event 8.0 11.0 hint Action
            .....
      end_event
      
    The "hint" argument is not required.

  • if_entry action command

    This is an "if" statement that checks to see if the action that was entered by the player during the PREVIOUS declared event is the same as the action command declared for this command. If it is the same, any commands proceeding this command will be executed. To "close off" this command, use the "end_entry" command at the end of the block.
      if_entry U
            .....
      end_entry
      
    Multiple instances can be declared, but will still only check the action for the PREVIOUS declared event.
      if_entry U
            .....
      end_entry
      if_entry R
            .....
      end_entry
      

  • if_miss

    This is an "if" statement that checks to see if the action that was entered by the player during the PREVIOUS declared event was not successful. An event is flagged "successful" if a entry was compared in a previous "if_entry" command. If not successful, any commands proceeding this command will be executed. To "close off" this command, use the "end_entry" command at the end of the block.
      if_miss
            .....
      end_entry
      
    This should be the last entry under an event, as the system checks previous "if_entry" commands. Multiple instances should not be declared, as it will cause the program to misbehave.

  • play _starting time of block_ _ending time of block_

    THIS COMMAND IS USED WITHIN IF BLOCKS. The program will play the specified block of video. The numbers are the "seconds" time frame of the video. The numbers are a "double" number (i.e. decimal), so that you can break them down into fractions of seconds for pinpoint accuracy.
      play 90.0 93.0
      
    This command does not "surrender control" of the system to a new time frame, such as with the "jump" command. The system will not execute any other commands until the specified block of has been played in its entirety.

    HINT: This command is useful for playing "death scenes."

  • jump time of video

    THIS COMMAND IS USED WITHIN IF BLOCKS. The program will jump to the specified time. The number is the "seconds" time frame of the video. The number is a "double" number (i.e. decimal), so that you can break it down into fractions of seconds for pinpoint accuracy.
      jump 100.0
      

  • scoremod score modifier

    THIS COMMAND IS USED WITHIN IF BLOCKS. The player's score will be modified by the specified amount. Can be a positive or negative number.
      scoremod 100
      

  • lifemod life modifier

    THIS COMMAND IS USED WITHIN IF BLOCKS. The player's number of lives be modified by the specified amount. Can be a positive or negative number.
      lifemod -1
      
    HINT: This command is useful during bonus areas to give players extra lives, or reducing lives during a missed action.

    08-12-2006