/frameworks/base/core/java/com/android/internal/display/BrightnessSynchronizer.java
修改最低亮度，不能太暗看不见
/**
* Converts between the int brightness system and the float brightness system.
*/
public static float brightnessIntToFloat(int brightnessInt) {
if (brightnessInt == PowerManager.BRIGHTNESS_OFF) {
return PowerManager.BRIGHTNESS_OFF_FLOAT;
} else if (brightnessInt == PowerManager.BRIGHTNESS_INVALID) {
return PowerManager.BRIGHTNESS_INVALID_FLOAT;
} else {
final float minFloat = PowerManager.BRIGHTNESS_MIN;
final float maxFloat = PowerManager.BRIGHTNESS_MAX;
/*/ add screen lowest brightness
final float minInt = PowerManager.BRIGHTNESS_OFF + 1;
//*/
final float minInt = 20;
//*/
final float maxInt = PowerManager.BRIGHTNESS_ON;
return MathUtils.constrainedMap(minFloat, maxFloat, minInt, maxInt, brightnessInt);
}
}
/**
* Converts between the float brightness system and the int brightness system.
*/
public static int brightnessFloatToInt(float brightnessFloat) {
return Math.round(brightnessFloatToIntRange(brightnessFloat));
}
/**
* Translates specified value from the float brightness system to the int brightness system,
* given the min/max of each range. Accounts for special values such as OFF and invalid values.
* Value returned as a float primitive (to preserve precision), but is a value within the
* int-system range.
*/
public static float brightnessFloatToIntRange(float brightnessFloat) {
if (floatEquals(brightnessFloat, PowerManager.BRIGHTNESS_OFF_FLOAT)) {
return PowerManager.BRIGHTNESS_OFF;
} else if (Float.isNaN(brightnessFloat)) {
return PowerManager.BRIGHTNESS_INVALID;
} else {
final float minFloat = PowerManager.BRIGHTNESS_MIN;
final float maxFloat = PowerManager.BRIGHTNESS_MAX;
/*/add screen lowest brightness
final float minInt = PowerManager.BRIGHTNESS_OFF + 1;
//*/
final float minInt = 20;
//*/
final float maxInt = PowerManager.BRIGHTNESS_ON;
return MathUtils.constrainedMap(minInt, maxInt, minFloat, maxFloat, brightnessFloat);
}
}
