package com.android.server.vr;
import static android.view.Display.INVALID_DISPLAY;
import android.app.ActivityManagerInternal;
import android.app.Vr2dDisplayProperties;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.graphics.PixelFormat;
import android.hardware.display.DisplayManager;
import android.hardware.display.VirtualDisplay;
import android.media.ImageReader;
import android.os.Build;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.RemoteException;
import android.os.ServiceManager;
import android.os.SystemProperties;
import android.service.vr.IPersistentVrStateCallbacks;
import android.service.vr.IVrManager;
import android.util.Log;
import android.view.Surface;
import com.android.server.wm.WindowManagerInternal;
/**
* Creates a 2D Virtual Display while VR Mode is enabled. This display will be used to run and
* render 2D app within a VR experience. For example, bringing up the 2D calculator app in VR.
*/
class Vr2dDisplay {
private final static String TAG = "Vr2dDisplay";
private final static boolean DEBUG = false;
private int mVirtualDisplayHeight;
private int mVirtualDisplayWidth;
private int mVirtualDisplayDpi;
private final static int STOP_VIRTUAL_DISPLAY_DELAY_MILLIS = 2000;
private final static String UNIQUE_DISPLAY_ID = "277f1a09-b88d-4d1e-8716-796f114d080b";
private final static String DISPLAY_NAME = "VR 2D Display";
private final static String DEBUG_ACTION_SET_MODE =
"com.android.server.vr.Vr2dDisplay.SET_MODE";
private final static String DEBUG_EXTRA_MODE_ON =
"com.android.server.vr.Vr2dDisplay.EXTRA_MODE_ON";
private final static String DEBUG_ACTION_SET_SURFACE =
"com.android.server.vr.Vr2dDisplay.SET_SURFACE";
private final static String DEBUG_EXTRA_SURFACE =
"com.android.server.vr.Vr2dDisplay.EXTRA_SURFACE";
/**
* The default width of the VR virtual display
*/
public static final int DEFAULT_VIRTUAL_DISPLAY_WIDTH = 1400;
/**
* The default height of the VR virtual display
*/
public static final int DEFAULT_VIRTUAL_DISPLAY_HEIGHT = 1800;
/**
* The default height of the VR virtual dpi.
*/
public static final int DEFAULT_VIRTUAL_DISPLAY_DPI = 320;
/**
* The minimum height, width and dpi of VR virtual display.
*/
public static final int MIN_VR_DISPLAY_WIDTH = 1;
public static final int MIN_VR_DISPLAY_HEIGHT = 1;
public static final int MIN_VR_DISPLAY_DPI = 1;
private final ActivityManagerInternal mActivityManagerInternal;
private final WindowManagerInternal mWindowManagerInternal;
private final DisplayManager mDisplayManager;
private final IVrManager mVrManager;
private final Object mVdLock = new Object();
private final Handler mHandler = new Handler();
/**
* Callback implementation to receive changes to VrMode.
**/
private final IPersistentVrStateCallbacks mVrStateCallbacks =
new IPersistentVrStateCallbacks.Stub() {
@Override
public void onPersistentVrStateChanged(boolean enabled) {
if (enabled != mIsPersistentVrModeEnabled) {
mIsPersistentVrModeEnabled = enabled;
updateVirtualDisplay();
}
}
};
private VirtualDisplay mVirtualDisplay;
private Surface mSurface;
private ImageReader mImageReader;
private Runnable mStopVDRunnable;
private boolean mIsVrModeOverrideEnabled; // debug override to set vr mode.
private boolean mIsVirtualDisplayAllowed = true; // Virtual-display feature toggle
private boolean mIsPersistentVrModeEnabled; // indicates we are in vr persistent mode.
private boolean mBootsToVr = false; // The device boots into VR (standalone VR device)
public Vr2dDisplay(DisplayManager displayManager,
ActivityManagerInternal activityManagerInternal,
WindowManagerInternal windowManagerInternal, IVrManager vrManager) {
mDisplayManager = displayManager;
mActivityManagerInternal = activityManagerInternal;
mWindowManagerInternal = windowManagerInternal;
mVrManager = vrManager;
mVirtualDisplayWidth = DEFAULT_VIRTUAL_DISPLAY_WIDTH;
mVirtualDisplayHeight = DEFAULT_VIRTUAL_DISPLAY_HEIGHT;
mVirtualDisplayDpi = DEFAULT_VIRTUAL_DISPLAY_DPI;
}
/**
* Initializes the compabilitiy display by listening to VR mode changes.
*/
public void init(Context context, boolean bootsToVr) {
startVrModeListener();
startDebugOnlyBroadcastReceiver(context);
mBootsToVr = bootsToVr;
if (mBootsToVr) {
// If we are booting into VR, we need to start the virtual display immediately. This
// ensures that the virtual display is up by the time Setup Wizard is started.
updateVirtualDisplay();
}
}
/**
* Creates and Destroys the virtual display depending on the current state of VrMode.
*/
private void updateVirtualDisplay() {
if (DEBUG) {
Log.i(TAG, "isVrMode: " + mIsPersistentVrModeEnabled + ", override: "
+ mIsVrModeOverrideEnabled + ", isAllowed: " + mIsVirtualDisplayAllowed
+ ", bootsToVr: " + mBootsToVr);
}
if (shouldRunVirtualDisplay()) {
Log.i(TAG, "Attempting to start virtual display");
// TODO: Consider not creating the display until ActivityManager needs one on
// which to display a 2D application.
startVirtualDisplay();
} else {
// Stop virtual display to test exit condition
stopVirtualDisplay();
}
}
/**
* Creates a DEBUG-only BroadcastReceiver through which a test app can simulate VrMode and
* set a custom Surface for the virtual display. This allows testing of the virtual display
* without going into full 3D.
*
* @param context The context.
*/
private void startDebugOnlyBroadcastReceiver(Context context) {
if (DEBUG) {
IntentFilter intentFilter = new IntentFilter(DEBUG_ACTION_SET_MODE);
intentFilter.addAction(DEBUG_ACTION_SET_SURFACE);
context.registerReceiver(new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (DEBUG_ACTION_SET_MODE.equals(action)) {
mIsVrModeOverrideEnabled =
intent.getBooleanExtra(DEBUG_EXTRA_MODE_ON, false);
updateVirtualDisplay();
} else if (DEBUG_ACTION_SET_SURFACE.equals(action)) {
if (mVirtualDisplay != null) {
if (intent.hasExtra(DEBUG_EXTRA_SURFACE)) {
setSurfaceLocked(intent.getParcelableExtra(DEBUG_EXTRA_SURFACE));
}
} else {
Log.w(TAG, "Cannot set the surface because the VD is null.");
}
}
}
}, intentFilter);
}
}
/**
* Starts listening to VrMode changes.
*/
private void startVrModeListener() {
if (mVrManager != null) {
try {
mVrManager.registerPersistentVrStateListener(mVrStateCallbacks);
} catch (RemoteException e) {
Log.e(TAG, "Could not register VR State listener.", e);
}
}
}
/**
* Sets the resolution and DPI of the Vr2d virtual display used to display
* 2D applications in VR mode.
*
* <p>Requires {@link android.Manifest.permission#ACCESS_VR_MANAGER} permission.</p>
*
* @param displayProperties Properties of the virtual display for 2D applications
* in VR mode.
*/
public void setVirtualDisplayProperties(Vr2dDisplayProperties displayProperties) {
synchronized(mVdLock) {
if (DEBUG) {
Log.i(TAG, "VD setVirtualDisplayProperties: " +
displayProperties.toString());
}
int width = displayProperties.getWidth();
int height = displayProperties.getHeight();
int dpi = displayProperties.getDpi();
boolean resized = false;
if (width < MIN_VR_DISPLAY_WIDTH || height < MIN_VR_DISPLAY_HEIGHT ||
dpi < MIN_VR_DISPLAY_DPI) {
Log.i(TAG, "Ignoring Width/Height/Dpi values of " + width + "," + height + ","
+ dpi);
} else {
Log.i(TAG, "Setting width/height/dpi to " + width + "," + height + "," + dpi);
mVirtualDisplayWidth = width;
mVirtualDisplayHeight = height;
mVirtualDisplayDpi = dpi;
resized = true;
}
if ((displayProperties.getFlags() & Vr2dDisplayProperties.FLAG_VIRTUAL_DISPLAY_ENABLED)
== Vr2dDisplayProperties.FLAG_VIRTUAL_DISPLAY_ENABLED) {
mIsVirtualDisplayAllowed = true;
} else if ((displayProperties.getRemovedFlags() &
Vr2dDisplayProperties.FLAG_VIRTUAL_DISPLAY_ENABLED)
== Vr2dDisplayProperties.FLAG_VIRTUAL_DISPLAY_ENABLED) {
mIsVirtualDisplayAllowed = false;
}
if (mVirtualDisplay != null && resized && mIsVirtualDisplayAllowed) {
mVirtualDisplay.resize(mVirtualDisplayWidth, mVirtualDisplayHeight,
mVirtualDisplayDpi);
ImageReader oldImageReader = mImageReader;
mImageReader = null;
startImageReader();
oldImageReader.close();
}
// Start/Stop the virtual display in case the updates indicated that we should.
updateVirtualDisplay();
}
}
/**
* Returns the virtual display ID if one currently exists, otherwise returns
* {@link INVALID_DISPLAY_ID}.
*
* @return The virtual display ID.
*/
public int getVirtualDisplayId() {
synchronized(mVdLock) {
if (mVirtualDisplay != null) {
int virtualDisplayId = mVirtualDisplay.getDisplay().getDisplayId();
if (DEBUG) {
Log.i(TAG, "VD id: " + virtualDisplayId);
}
return virtualDisplayId;
}
}
return INVALID_DISPLAY;
}
/**
* Starts the virtual display if one does not already exist.
*/
private void startVirtualDisplay() {
if (DEBUG) {
Log.d(TAG, "Request to start VD, DM:" + mDisplayManager);
}
if (mDisplayManager == null) {
Log.w(TAG, "Cannot create virtual display because mDisplayManager == null");
return;
}
synchronized (mVdLock) {
if (mVirtualDisplay != null) {
Log.i(TAG, "VD already exists, ignoring request");
return;
}
int flags = DisplayManager.VIRTUAL_DISPLAY_FLAG_SUPPORTS_TOUCH;
flags |= DisplayManager.VIRTUAL_DISPLAY_FLAG_ROTATES_WITH_CONTENT;
flags |= DisplayManager.VIRTUAL_DISPLAY_FLAG_PUBLIC;
flags |= DisplayManager.VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY;
flags |= DisplayManager.VIRTUAL_DISPLAY_FLAG_DESTROY_CONTENT_ON_REMOVAL;
mVirtualDisplay = mDisplayManager.createVirtualDisplay(null /* projection */,
DISPLAY_NAME, mVirtualDisplayWidth, mVirtualDisplayHeight, mVirtualDisplayDpi,
null /* surface */, flags, null /* callback */, null /* handler */,
UNIQUE_DISPLAY_ID);
if (mVirtualDisplay != null) {
updateDisplayId(mVirtualDisplay.getDisplay().getDisplayId());
// Now create the ImageReader to supply a Surface to the new virtual display.
startImageReader();
} else {
Log.w(TAG, "Virtual display id is null after createVirtualDisplay");
updateDisplayId(INVALID_DISPLAY);
return;
}
}
Log.i(TAG, "VD created: " + mVirtualDisplay);
}
private void updateDisplayId(int displayId) {
mActivityManagerInternal.setVr2dDisplayId(displayId);
mWindowManagerInternal.setVr2dDisplayId(displayId);
}
/**
* Stops the virtual display with a {@link #STOP_VIRTUAL_DISPLAY_DELAY_MILLIS} timeout.
* The timeout prevents the virtual display from bouncing in cases where VrMode goes in and out
* of being enabled. This can happen sometimes with our 2D test app.
*/
private void stopVirtualDisplay() {
if (mStopVDRunnable == null) {
mStopVDRunnable = new Runnable() {
@Override
public void run() {
if (shouldRunVirtualDisplay()) {
Log.i(TAG, "Virtual Display destruction stopped: VrMode is back on.");
} else {
Log.i(TAG, "Stopping Virtual Display");
synchronized (mVdLock) {
updateDisplayId(INVALID_DISPLAY);
setSurfaceLocked(null); // clean up and release the surface first.
if (mVirtualDisplay != null) {
mVirtualDisplay.release();
mVirtualDisplay = null;
}
stopImageReader();
}
}
}
};
}
mHandler.removeCallbacks(mStopVDRunnable);
mHandler.postDelayed(mStopVDRunnable, STOP_VIRTUAL_DISPLAY_DELAY_MILLIS);
}
/**
* Set the surface to use with the virtual display.
*
* Code should be locked by {@link #mVdLock} before invoked.
*
* @param surface The Surface to set.
*/
private void setSurfaceLocked(Surface surface) {
// Change the surface to either a valid surface or a null value.
if (mSurface != surface && (surface == null || surface.isValid())) {
Log.i(TAG, "Setting the new surface from " + mSurface + " to " + surface);
if (mVirtualDisplay != null) {
mVirtualDisplay.setSurface(surface);
}
if (mSurface != null) {
mSurface.release();
}
mSurface = surface;
}
}
/**
* Starts an ImageReader as a do-nothing Surface. The virtual display will not get fully
* initialized within surface flinger unless it has a valid Surface associated with it. We use
* the ImageReader as the default valid Surface.
*/
private void startImageReader() {
if (mImageReader == null) {
mImageReader = ImageReader.newInstance(mVirtualDisplayWidth, mVirtualDisplayHeight,
PixelFormat.RGBA_8888, 2 /* maxImages */);
Log.i(TAG, "VD startImageReader: res = " + mVirtualDisplayWidth + "X" +
mVirtualDisplayHeight + ", dpi = " + mVirtualDisplayDpi);
}
synchronized (mVdLock) {
setSurfaceLocked(mImageReader.getSurface());
}
}
/**
* Cleans up the ImageReader.
*/
private void stopImageReader() {
if (mImageReader != null) {
mImageReader.close();
mImageReader = null;
}
}
private boolean shouldRunVirtualDisplay() {
// Virtual Display should run whenever:
// * Virtual Display is allowed/enabled AND
// (1) BootsToVr is set indicating the device never leaves VR
// (2) VR (persistent) mode is enabled
// (3) VR mode is overridden to be enabled.
return mIsVirtualDisplayAllowed &&
(mBootsToVr || mIsPersistentVrModeEnabled || mIsVrModeOverrideEnabled);
}
}