Flixel Collision Notes

//This call:
collision_cratesVSmap(crateStormGroup, collisionMap);

//is equivalent in affect to this call:
FlxG.collide(crateStormGroup, collisionMap, crateOnWallAction);

private function collision_cratesVSmap(objectOrGroup1:FlxBasic, objectOrGroup2:FlxBasic):void
{
 FlxG.overlap(objectOrGroup1, objectOrGroup2, crateOnWallAction, FlxObject.separate);
}

private function crateOnWallAction(b1:FlxBasic, b2:FlxBasic):void
{
 //get the object that is NOT the wall, but our sprite.
 var b:FlxSprite;
 if (b1 is FlxSprite) { b = b1 as FlxSprite; }
 else
 if (b2 is FlxSprite) { b = b2 as FlxSprite; }
 
 if (b1 is Sprite && b2 is Sprite) { throw new Error("both sprites"); }
 
 b.acceleration.x = 0 - b.acceleration.x;
 b.acceleration.y = 0 - b.acceleration.y;
}