LevelScripting

Level Scripting

Levels are defined in the following XML file: resources/xml/levels.xml

The level set is made of levels and functions, which are some kind of sub-levels. Both work the same, except functions are identified by a name, whereas levels are organized in an ordered sequence:

<?xml version="1.0" encoding="utf-8" ?>
<levelset>
    <functions>
        <def name="function_a">...</def>
        <def name="function_b">...</def>
    </functions>
    <levels>
        <level>... level 1 ...</level>
        <level>... level 2 ...</level>    
    </levels>
</levelset>

Functions cannot be directly accessed from the game, and must be called from a level or from another function.

Function tags

Each function is defined by a def tag and a unique name attribute.

Level tags

Each level is defined by a level tag. You can set the following attributes:

• layer1: path to the bottom background image
• layer2: path to the top background image
• color: color applied to the layers (HTML hex notation, example: "#3483b3")
• stars: amount of stars scrolling in the background (integer)
• music: path to music file

Entity and control tags

A level or a function contains the following tags:

• ship: create a spaceship
  • id: spaceship type (see xml/spaceships.xml for more information)
  • x: initial x position
  • y: initial y position (screen right edge if not provided)
  • t: time to wait in seconds before spaceship is created, from the last created spaceship (0 if not provided)
• asteroid: create an asteroid
  • x, y, t: see above
• boss: create a end boss
  • id: boss type (hard coded string)
  • x, y, t: see above
• decor: create a decor with a fixed position
  • id: decor type (hard coded string)
  • t: see above
• loop: repeat all the inner tags
  • count: iteration count
• call: call a function
  • func: name of the called function
• wait: delay the next instruction
  • t: time to wait before the next instruction (seconds)

Using loops and functions allow factorizing repeated sequences, or sequences shared between several levels. You can use nested loops, and function calls inside functions.