Worm | Step-by-step tutorial

The classic game of 'Snake' with a two to four player twist. Can you eat the most fruit and be the last worm alive?

In this tutorial we introduce the concept of spritesheets as a memory efficient store of level data for games that require the player to navigate a 2D map or static platforms. Learn how to store spritesheets in a tilesource and then create a game level using a tilemap from the tilesource. This tutorial assumes you already have a knowledge of building games in Defold including input bindings, game objects and scripts. If not, you should attempt the previous tutorials first.

• Stage 1: building the skeletal structure of the game:
  • 1a: creating the collections for the game;
  • 1b: writing a script for the controller.
• Stage 2: creating a GUI for the title screen:
  • 2a: changing the game properties and creating the atlas;
  • 2b: building the interface with graphics and buttons;
  • 2c: creating the Gui script.
• Stage 3: creating the playing field:
  • 3a: creating a tile source;
  • 3b creating a tile map.
• Stage 4: adding a worm:
  • 4a: spawning player 1;
  • 4b: handling the inputs;
  • 4c moving the worm.
• Stage 5: eating food:
  • 5a: spawning fruit;
  • 5b: collision detection with fruit;
  • 5c: growing the worm.
• Stage 6: collision detection with other objects:
  • 6a: colliding with walls and worm segments;
  • 6b: handling no worms left alive.
• Stage 7: adding the second player.
• Stage 8: hiding the mouse.
• Stage 9: adding some 'snap'.
• Stage 10: adding some 'crackle'.
• Stage 11: adding some 'pop'.

This tutorial has sufficient complexity to be a programming project for OCR A level Computer Science, and comfortably a group B project for AQA A level Computer Science.

What you learned in this tutorial

1. A tile source holds equally sized bitmaps (tiles) that allow you to construct graphics for top-down levels and platform games easily.
2. A tile map uses the graphics in a tile source to construct a level either at design or run-time.
3. Each image in the tile source has a unique number that is applied to the tile map when a tile is placed. The tile map is a large 2D array storing the value of the tile placed in that position which you can manipulate using script code.
4. Higher-order data structures such as queues can be used to track objects that are made of many parts.
5. Libraries extend the functionality of a programming language by including code in your project that other people have written.