scrcpy/server/src/main/java/com/genymobile/scrcpy/video/ScreenInfo.java

package com.genymobile.scrcpy.video;

import com.genymobile.scrcpy.device.Device;
import com.genymobile.scrcpy.device.Size;
import com.genymobile.scrcpy.util.Ln;

import android.graphics.Rect;

public final class ScreenInfo {
    /**
     * Device (physical) size, possibly cropped
     */
    private final Rect contentRect; // device size, possibly cropped

    /**
     * Video size, possibly smaller than the device size, already taking the device rotation and crop into account.
     * <p>
     * However, it does not include the locked video orientation.
     */
    private final Size unlockedVideoSize;

    /**
     * Device rotation, related to the natural device orientation (0, 1, 2 or 3)
     */
    private final int deviceRotation;

    /**
     * The locked video orientation (-1: disabled, 0: normal, 1: 90° CCW, 2: 180°, 3: 90° CW)
     */
    private final int lockedVideoOrientation;

    public ScreenInfo(Rect contentRect, Size unlockedVideoSize, int deviceRotation, int lockedVideoOrientation) {
        this.contentRect = contentRect;
        this.unlockedVideoSize = unlockedVideoSize;
        this.deviceRotation = deviceRotation;
        this.lockedVideoOrientation = lockedVideoOrientation;
    }

    public Rect getContentRect() {
        return contentRect;
    }

    /**
     * Return the video size as if locked video orientation was not set.
     *
     * @return the unlocked video size
     */
    public Size getUnlockedVideoSize() {
        return unlockedVideoSize;
    }

    /**
     * Return the actual video size if locked video orientation is set.
     *
     * @return the actual video size
     */
    public Size getVideoSize() {
        if (getVideoRotation() % 2 == 0) {
            return unlockedVideoSize;
        }

        return unlockedVideoSize.rotate();
    }

    public static ScreenInfo computeScreenInfo(int rotation, Size deviceSize, Rect crop, int maxSize, int lockedVideoOrientation) {
        if (lockedVideoOrientation == Device.LOCK_VIDEO_ORIENTATION_INITIAL) {
            // The user requested to lock the video orientation to the current orientation
            lockedVideoOrientation = rotation;
        }

        Rect contentRect = new Rect(0, 0, deviceSize.getWidth(), deviceSize.getHeight());
        if (crop != null) {
            if (rotation % 2 != 0) { // 180s preserve dimensions
                // the crop (provided by the user) is expressed in the natural orientation
                crop = flipRect(crop);
            }
            if (!contentRect.intersect(crop)) {
                // intersect() changes contentRect so that it is intersected with crop
                Ln.w("Crop rectangle (" + formatCrop(crop) + ") does not intersect device screen (" + formatCrop(deviceSize.toRect()) + ")");
                contentRect = new Rect(); // empty
            }
        }

        Size videoSize = new Size(contentRect.width(), contentRect.height()).limit(maxSize).round8();
        return new ScreenInfo(contentRect, videoSize, rotation, lockedVideoOrientation);
    }

    private static String formatCrop(Rect rect) {
        return rect.width() + ":" + rect.height() + ":" + rect.left + ":" + rect.top;
    }

    private static Rect flipRect(Rect crop) {
        return new Rect(crop.top, crop.left, crop.bottom, crop.right);
    }

    /**
     * Return the rotation to apply to the device rotation to get the requested locked video orientation
     *
     * @return the rotation offset
     */
    public int getVideoRotation() {
        if (lockedVideoOrientation == -1) {
            // no offset
            return 0;
        }
        return (deviceRotation + 4 - lockedVideoOrientation) % 4;
    }

    /**
     * Return the rotation to apply to the requested locked video orientation to get the device rotation
     *
     * @return the (reverse) rotation offset
     */
    public int getReverseVideoRotation() {
        if (lockedVideoOrientation == -1) {
            // no offset
            return 0;
        }
        return (lockedVideoOrientation + 4 - deviceRotation) % 4;
    }
}