Add capture prepare() step

Add a function called before each capture starts (before getSize() is
called).

This allows to compute the ScreenInfo instance once exactly when needed.

PR #5370 <https://github.com/Genymobile/scrcpy/pull/5370>

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

@@ -26,9 +26,8 @@ public class ScreenCapture extends SurfaceCapture {
     private int maxSize;
     private final Rect crop;
     private final int lockVideoOrientation;
-    private int layerStack;
 
-    private Size deviceSize;
+    private DisplayInfo displayInfo;
     private ScreenInfo screenInfo;
 
     private IBinder display;
@@ -46,27 +45,11 @@ public class ScreenCapture extends SurfaceCapture {
     }
 
     @Override
-    public void init() throws ConfigurationException {
-        DisplayInfo displayInfo = ServiceManager.getDisplayManager().getDisplayInfo(displayId);
-        if (displayInfo == null) {
-            Ln.e("Display " + displayId + " not found\n" + LogUtils.buildDisplayListMessage());
-            throw new ConfigurationException("Unknown display id: " + displayId);
-        }
-
-        deviceSize = displayInfo.getSize();
-        ScreenInfo si = ScreenInfo.computeScreenInfo(displayInfo.getRotation(), deviceSize, crop, maxSize, lockVideoOrientation);
-        setScreenInfo(si);
-        layerStack = displayInfo.getLayerStack();
-
+    public void init() {
         if (displayId == 0) {
             rotationWatcher = new IRotationWatcher.Stub() {
                 @Override
                 public void onRotationChanged(int rotation) {
-                    synchronized (ScreenCapture.this) {
-                        ScreenInfo si = screenInfo.withDeviceRotation(rotation);
-                        setScreenInfo(si);
-                    }
-
                     requestReset();
                 }
             };
@@ -91,27 +74,26 @@ public class ScreenCapture extends SurfaceCapture {
                         return;
                     }
 
-                    synchronized (ScreenCapture.this) {
-                        DisplayInfo displayInfo = ServiceManager.getDisplayManager().getDisplayInfo(displayId);
-                        if (displayInfo == null) {
-                            Ln.e("Display " + displayId + " not found\n" + LogUtils.buildDisplayListMessage());
-                            return;
-                        }
-
-                        deviceSize = displayInfo.getSize();
-                        ScreenInfo si = ScreenInfo.computeScreenInfo(displayInfo.getRotation(), deviceSize, crop, maxSize, lockVideoOrientation);
-                        setScreenInfo(si);
-                    }
-
                     requestReset();
                 }
             };
             ServiceManager.getWindowManager().registerDisplayFoldListener(displayFoldListener);
         }
+    }
+
+    @Override
+    public void prepare() throws ConfigurationException {
+        displayInfo = ServiceManager.getDisplayManager().getDisplayInfo(displayId);
+        if (displayInfo == null) {
+            Ln.e("Display " + displayId + " not found\n" + LogUtils.buildDisplayListMessage());
+            throw new ConfigurationException("Unknown display id: " + displayId);
+        }
 
         if ((displayInfo.getFlags() & DisplayInfo.FLAG_SUPPORTS_PROTECTED_BUFFERS) == 0) {
             Ln.w("Display doesn't have FLAG_SUPPORTS_PROTECTED_BUFFERS flag, mirroring can be restricted");
         }
+
+        screenInfo = ScreenInfo.computeScreenInfo(displayInfo.getRotation(), displayInfo.getSize(), crop, maxSize, lockVideoOrientation);
     }
 
     @Override
@@ -139,6 +121,7 @@ public class ScreenCapture extends SurfaceCapture {
                 // does not include the locked video orientation
                 Rect unlockedVideoRect = screenInfo.getUnlockedVideoSize().toRect();
                 int videoRotation = screenInfo.getVideoRotation();
+                int layerStack = displayInfo.getLayerStack();
 
                 setDisplaySurface(display, surface, videoRotation, contentRect, unlockedVideoRect, layerStack);
                 Ln.d("Display: using SurfaceControl API");
@@ -148,6 +131,8 @@ public class ScreenCapture extends SurfaceCapture {
                 throw new AssertionError("Could not create display");
             }
         }
+
+        device.setScreenInfo(screenInfo);
     }
 
     @Override
@@ -169,15 +154,13 @@ public class ScreenCapture extends SurfaceCapture {
     }
 
     @Override
-    public synchronized Size getSize() {
+    public Size getSize() {
         return screenInfo.getVideoSize();
     }
 
     @Override
-    public synchronized boolean setMaxSize(int newMaxSize) {
+    public boolean setMaxSize(int newMaxSize) {
         maxSize = newMaxSize;
-        ScreenInfo si = ScreenInfo.computeScreenInfo(screenInfo.getReverseVideoRotation(), deviceSize, crop, newMaxSize, lockVideoOrientation);
-        setScreenInfo(si);
         return true;
     }
 
@@ -199,9 +182,4 @@ public class ScreenCapture extends SurfaceCapture {
             SurfaceControl.closeTransaction();
         }
     }
-
-    private void setScreenInfo(ScreenInfo si) {
-        screenInfo = si;
-        device.setScreenInfo(si);
-    }
 }

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

@@ -63,28 +63,6 @@ public final class ScreenInfo {
         return unlockedVideoSize.rotate();
     }
 
-    public int getDeviceRotation() {
-        return deviceRotation;
-    }
-
-    public ScreenInfo withDeviceRotation(int newDeviceRotation) {
-        if (newDeviceRotation == deviceRotation) {
-            return this;
-        }
-        // true if changed between portrait and landscape
-        boolean orientationChanged = (deviceRotation + newDeviceRotation) % 2 != 0;
-        Rect newContentRect;
-        Size newUnlockedVideoSize;
-        if (orientationChanged) {
-            newContentRect = flipRect(contentRect);
-            newUnlockedVideoSize = unlockedVideoSize.rotate();
-        } else {
-            newContentRect = contentRect;
-            newUnlockedVideoSize = unlockedVideoSize;
-        }
-        return new ScreenInfo(newContentRect, newUnlockedVideoSize, newDeviceRotation, lockedVideoOrientation);
-    }
-
     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

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

@@ -33,15 +33,22 @@ public abstract class SurfaceCapture {
     }
 
     /**
-     * Called once before the capture starts.
+     * Called once before the first capture starts.
      */
     public abstract void init() throws ConfigurationException, IOException;
 
     /**
-     * Called after the capture ends (if and only if {@link #init()} has been called).
+     * Called after the last capture ends (if and only if {@link #init()} has been called).
      */
     public abstract void release();
 
+    /**
+     * Called once before each capture starts, before {@link #getSize()}.
+     */
+    public void prepare() throws ConfigurationException {
+        // empty by default
+    }
+
     /**
      * Start the capture to the target surface.
      *

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

@@ -72,6 +72,7 @@ public class SurfaceEncoder implements AsyncProcessor {
             boolean headerWritten = false;
 
             do {
+                capture.prepare();
                 Size size = capture.getSize();
                 if (!headerWritten) {
                     streamer.writeVideoHeader(size);