PHP Objects, Patterns, and Practice, Third Edition

CHAPTER 9 ■ GENERATING OBJECTS

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object state when you generate new products. Imagine that Sea objects have a $navigability property.

The property influences the amount of movement energy a sea tile saps from a vessel and can be set to

adjust the difficulty level of a game:

class Sea {

private $navigability = 0;

function __construct( $navigability ) {

$this->navigability = $navigability;

}

}

Now, when I initialize the TerrainFactory object, I can add a Sea object with a navigability modifier.

This will then hold true for all Sea objects served by TerrainFactory:

$factory = new TerrainFactory( new EarthSea( -1 ),

new EarthPlains(),

new ...