Java programming with Greenfoot: lettuce is good for you (collision detection)
In this video tutorial the concept of collision detection is introduced. This is a key aspect of many games – recognising that two objects are touching. This is explained with the creation of a lettuce class within the game. When the turtle touches a lettuce it appears to eat it and so it disappears. This is modelled via the use of an if statement. This tutorial also introduces the save world function so that a student can save their programme in its current state and run it from their rather than returning to the beginning.
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