| /* |
| * Copyright (C) 2020 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package android.hardware.light; |
| |
| @VintfStability |
| enum BrightnessMode { |
| /** |
| * Light brightness is managed by a user setting. |
| */ |
| USER = 0, |
| |
| /** |
| * Light brightness is managed by a light sensor. This is typically used |
| * to control the display backlight, but not limited to it. HALs and |
| * hardware implementations are free to support sensor for other lights or |
| * none whatsoever. |
| */ |
| SENSOR = 1, |
| |
| /** |
| * Use a low-persistence mode for display backlights, where the pixel |
| * color transition times are lowered. |
| * |
| * When set, the device driver must switch to a mode optimized for low display |
| * persistence that is intended to be used when the device is being treated as a |
| * head mounted display (HMD). The actual display brightness in this mode is |
| * implementation dependent, and any value set for color in LightState may be |
| * overridden by the HAL implementation. |
| * |
| * For an optimal HMD viewing experience, the display must meet the following |
| * criteria in this mode: |
| * - Gray-to-Gray, White-to-Black, and Black-to-White switching time must be ≤ 3 ms. |
| * - The display must support low-persistence with ≤ 3.5 ms persistence. |
| * Persistence is defined as the amount of time for which a pixel is |
| * emitting light for a single frame. |
| * - Any "smart panel" or other frame buffering options that increase display |
| * latency are disabled. |
| * - Display brightness is set so that the display is still visible to the user |
| * under normal indoor lighting. |
| * - The display must update at 60 Hz at least, but higher refresh rates are |
| * recommended for low latency. |
| * |
| */ |
| LOW_PERSISTENCE = 2, |
| } |