4 
UCLASS(abstract, config=Game, BlueprintType, hidecategories=("Pawn|Character|InternalEvents"))
class ENGINE_API ACharacter : public APawn
{
    GENERATED_UCLASS_BODY() 
...
    UPROPERTY(Transient)
    uint32 bClientWasFalling:1; 

    /** If server disagrees with root motion track position, client has to resimulate root motion from last AckedMove. */
    UPROPERTY(Transient)
    uint32 bClientResimulateRootMotion:1;

    /** Disable simulated gravity (set when character encroaches geometry on client, to keep him from falling through floors) */
    UPROPERTY()
    uint32 bSimGravityDisabled:1;

    /** 
     * Jump key Held Time.
     * This is the time that the player has held the jump key, in seconds.
     */
    UPROPERTY(Transient, BlueprintReadOnly, VisibleInstanceOnly, Category=Character)
    float JumpKeyHoldTime;

上面的代码来自 UE4。他们似乎使用 uint32 一位位域而不是布尔值。他们为什么这样做？

4

1 回答 1

9

独立文件bool至少有一个字节长。处理器不能处理更小的单元。但是，我们都知道一个字节可以容纳 8 位/布尔值，因此，如果您有一个具有多个布尔值的数据结构，则每个字节都不需要一个字节。他们可以共享一个字节。如果你有很多这样的结构，它可能会节省一些内存。

于 2014-10-20T16:12:59.317 回答