cmd_brightness

command: /brightness

quick ref:

/brightness [0-1]

description:

set brightness factor (0-1) used in HDR shader 3, 4. default value is 0.5. the larger the more detail in brighter region. 
/brightness 0.1    more detail with dark colors
/brightness 0.8    more detail with bright colors

设置亮度值(0 - 1)，默认值是0.5。