grayscale n.灰度，灰度圖
grayout是指某人因氧氣缺乏引起的暫時性視覺模糊，是視覺上的灰度，是身體因素 eg: A greyout is a transient loss of vision characterized by a perceived dimming of light and color.
grayscale是指某事物呈現灰色狀態，是物質屬性 eg: This code also creates a random graycale color for each quad.