FAttachmentTransformRules

/** Rules for attaching components */
struct ENGINE_API FAttachmentTransformRules
{
	/** Various preset attachment rules. Note that these default rules do NOT by default weld simulated bodies */
	static FAttachmentTransformRules KeepRelativeTransform;
	static FAttachmentTransformRules KeepWorldTransform;
	static FAttachmentTransformRules SnapToTargetNotIncludingScale;
	static FAttachmentTransformRules SnapToTargetIncludingScale;

	FAttachmentTransformRules(EAttachmentRule InRule, bool bInWeldSimulatedBodies)
		: LocationRule(InRule)
		, RotationRule(InRule)
		, ScaleRule(InRule)
		, bWeldSimulatedBodies(bInWeldSimulatedBodies)
	{}

	FAttachmentTransformRules(EAttachmentRule InLocationRule, EAttachmentRule InRotationRule, EAttachmentRule InScaleRule, bool bInWeldSimulatedBodies)
		: LocationRule(InLocationRule)
		, RotationRule(InRotationRule)
		, ScaleRule(InScaleRule)
		, bWeldSimulatedBodies(bInWeldSimulatedBodies)
	{}

	/** The rule to apply to location when attaching */
	EAttachmentRule LocationRule;

	/** The rule to apply to rotation when attaching */
	EAttachmentRule RotationRule;

	/** The rule to apply to scale when attaching */
	EAttachmentRule ScaleRule;

	/** Whether to weld simulated bodies together when attaching */
	bool bWeldSimulatedBodies;
};

• KeepRelativeTransform 保持两个物体的相对位置不变
• KeepWorldTransform 保持两个物体的世界位置不变
• SnapToTargetNotIncludingScale 忽略缩放对齐到目标
• SnapToTargetIncludingScale 保持比例对齐到目标