Just replace all Object
occurrences with PlacedMorph
:
PlacedMorph subclass: #SpaceWar instanceVariableNames: 'centralStar ships torpedoes' classVariableNames: '' poolDictionaries: '' category: 'Spacewar!' PlacedMorph subclass: #CentralStar instanceVariableNames: 'mass' classVariableNames: '' poolDictionaries: '' category: 'Spacewar!' PlacedMorph subclass: #SpaceShip instanceVariableNames: 'name position heading velocity fuel torpedoes mass acceleration' classVariableNames: '' poolDictionaries: '' category: 'Spacewar!'
Mobile subclass: #SpaceShip instanceVariableNames: 'name fuel torpedoes' classVariableNames: '' poolDictionaries: '' category: 'Spacewar!' Mobile subclass: #Torpedo instanceVariableNames: 'lifeSpan' classVariableNames: '' poolDictionaries: '' category: 'Spacewar!'