Status bar face hysteresis
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When the player's health moves between ranges corresponding to different status bar face animations, the red HEALTH percentage changes immediately, but the face itself is not updated until the end of the current animation sequence.
For example, if a severely injured player (below 20% health) gains a new weapon, followed closely by a large health pickup such as a megasphere, the status bar briefly displays a very high health percentage alongside an extremely bloodied face, as shown in the figure.
Another similar bug occurs when the IDKFA cheat is used. Because this cheat gives weapons to the player in a different manner than picking them up, the "new weapon" grin face is not displayed by the status bar when the cheat is activated. However, the next time the player collects any item, the status bar will then notice the change in weapons owned and the "new weapon" grinning face will be displayed at that time, even if the item being collected is a weapon already possessed or an unrelated thing, like health bonus.
