configstore/1.2/ISurfaceFlingerConfigs.hal

/*
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.1 (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-2.1
 *
 * 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.configstore@1.2;

import android.hardware.graphics.common@1.1::PixelFormat;
import android.hardware.graphics.common@1.2::Dataspace;
import @1.1::ISurfaceFlingerConfigs;
import @1.0::OptionalBool;

/**
 * New revision of ISurfaceFlingerConfigs
 */
interface ISurfaceFlingerConfigs extends @1.1::ISurfaceFlingerConfigs {
    /**
     * useColorManagement indicates whether SurfaceFlinger should manage color
     * by switching to appropriate color mode automatically depending on the
     * Dataspace of the surfaces on screen.
     * This function must return true when hasWideColorDisplay or hasHDRDisplay
     * return true.
     */
    useColorManagement() generates (OptionalBool value);

    /**
     * Returns the default data space and pixel format that SurfaceFlinger
     * expects to receive and output as well as the wide color gamut data space
     * and pixel format for wide color gamut surfaces.
     * To determine the data space and pixel format, there are a few things
     * we recommend to consider:
     *
     *   1. Hardware composer's capability to composite contents with the chosen
     *      data space and pixel format efficiently;
     *   2. Hardware composer's ability to composite contents when sRGB contents
     *      and the chosen wide color gamut data space contents coexist;
     *   3. For better blending, consider using pixel format where the alpha
     *      channel has as many bits as the RGB color channel.
     *   4. Memory consumption and efficient buffer compression when considering
     *      more bits in pixel format.
     *
     * @return dataspace is the default data space that SurfaceFlinger expects.
     *         The data space must not be Dataspace::UNKNOWN, if unspecified,
     *         the default data space is Dataspace::V0_SRGB;
     * @return pixelFormat is the default pixel format that SurfaceFlinger
     *         expects. If unspecified, the default pixel format is
     *         PixelFormat::RGBA_8888.
     * @return wcgDataspace is the data space that SurfaceFlinger expects for
     *         wide color gamut surfaces.
     *         When hasWideColorDisplay returns true, this API must return a
     *         valid wide color gamut data space.
     *         The data space must not be UNKNOWN, if unspecified, the data space
     *         is V0_SRGB by default, which essentially indicates there's no wide
     *         color gamut, meaning hasWideColorDisplay returns false.
     * @return wcgPixelFormat is the pixel format that SurfaceFlinger expects for
     *         wide color gamut surfaces. If unspecified, the pixel format is
     *         PixelFormat::RGBA_8888 by default.
     */
    getCompositionPreference()
        generates (Dataspace dataspace, PixelFormat pixelFormat,
                   Dataspace wcgDataspace, PixelFormat wcgPixelFormat);
};