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|
/*
* Copyright (C) 2007 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.view;
import dalvik.system.CloseGuard;
import android.content.res.CompatibilityInfo.Translator;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Rect;
import android.graphics.Region;
import android.graphics.SurfaceTexture;
import android.os.IBinder;
import android.os.Parcelable;
import android.os.Parcel;
import android.os.SystemProperties;
import android.util.Log;
/**
* Handle onto a raw buffer that is being managed by the screen compositor.
*/
public class Surface implements Parcelable {
private static final String TAG = "Surface";
private static final boolean HEADLESS = "1".equals(
SystemProperties.get("ro.config.headless", "0"));
public static final Parcelable.Creator<Surface> CREATOR =
new Parcelable.Creator<Surface>() {
public Surface createFromParcel(Parcel source) {
try {
Surface s = new Surface();
s.readFromParcel(source);
return s;
} catch (Exception e) {
Log.e(TAG, "Exception creating surface from parcel", e);
return null;
}
}
public Surface[] newArray(int size) {
return new Surface[size];
}
};
/**
* Rotation constant: 0 degree rotation (natural orientation)
*/
public static final int ROTATION_0 = 0;
/**
* Rotation constant: 90 degree rotation.
*/
public static final int ROTATION_90 = 1;
/**
* Rotation constant: 180 degree rotation.
*/
public static final int ROTATION_180 = 2;
/**
* Rotation constant: 270 degree rotation.
*/
public static final int ROTATION_270 = 3;
/* built-in physical display ids (keep in sync with ISurfaceComposer.h)
* these are different from the logical display ids used elsewhere in the framework */
/**
* Built-in physical display id: Main display.
* Use only with {@link #getBuiltInDisplay()}.
* @hide
*/
public static final int BUILT_IN_DISPLAY_ID_MAIN = 0;
/**
* Built-in physical display id: Attached HDMI display.
* Use only with {@link #getBuiltInDisplay()}.
* @hide
*/
public static final int BUILT_IN_DISPLAY_ID_HDMI = 1;
/* flags used in constructor (keep in sync with ISurfaceComposerClient.h) */
/**
* Surface creation flag: Surface is created hidden
* @hide */
public static final int HIDDEN = 0x00000004;
/**
* Surface creation flag: The surface contains secure content, special
* measures will be taken to disallow the surface's content to be copied
* from another process. In particular, screenshots and VNC servers will
* be disabled, but other measures can take place, for instance the
* surface might not be hardware accelerated.
* @hide
*/
public static final int SECURE = 0x00000080;
/**
* Surface creation flag: Creates a surface where color components are interpreted
* as "non pre-multiplied" by their alpha channel. Of course this flag is
* meaningless for surfaces without an alpha channel. By default
* surfaces are pre-multiplied, which means that each color component is
* already multiplied by its alpha value. In this case the blending
* equation used is:
*
* DEST = SRC + DEST * (1-SRC_ALPHA)
*
* By contrast, non pre-multiplied surfaces use the following equation:
*
* DEST = SRC * SRC_ALPHA * DEST * (1-SRC_ALPHA)
*
* pre-multiplied surfaces must always be used if transparent pixels are
* composited on top of each-other into the surface. A pre-multiplied
* surface can never lower the value of the alpha component of a given
* pixel.
*
* In some rare situations, a non pre-multiplied surface is preferable.
* @hide
*/
public static final int NON_PREMULTIPLIED = 0x00000100;
/**
* Surface creation flag: Indicates that the surface must be considered opaque,
* even if its pixel format is set to translucent. This can be useful if an
* application needs full RGBA 8888 support for instance but will
* still draw every pixel opaque.
* @hide
*/
public static final int OPAQUE = 0x00000400;
/**
* Surface creation flag: Application requires a hardware-protected path to an
* external display sink. If a hardware-protected path is not available,
* then this surface will not be displayed on the external sink.
* @hide
*/
public static final int PROTECTED_APP = 0x00000800;
// 0x1000 is reserved for an independent DRM protected flag in framework
/**
* Surface creation flag: Creates a normal surface.
* This is the default.
* @hide
*/
public static final int FX_SURFACE_NORMAL = 0x00000000;
/**
* Surface creation flag: Creates a Blur surface.
* Everything behind this surface is blurred by some amount.
* The quality and refresh speed of the blur effect is not settable or guaranteed.
* It is an error to lock a Blur surface, since it doesn't have a backing store.
* @hide
* @deprecated
*/
@Deprecated
public static final int FX_SURFACE_BLUR = 0x00010000;
/**
* Surface creation flag: Creates a Dim surface.
* Everything behind this surface is dimmed by the amount specified
* in {@link #setAlpha}. It is an error to lock a Dim surface, since it
* doesn't have a backing store.
* @hide
*/
public static final int FX_SURFACE_DIM = 0x00020000;
/**
* @hide
*/
public static final int FX_SURFACE_SCREENSHOT = 0x00030000;
/**
* Mask used for FX values above.
* @hide
*/
public static final int FX_SURFACE_MASK = 0x000F0000;
/* flags used with setFlags() (keep in sync with ISurfaceComposer.h) */
/**
* Surface flag: Hide the surface.
* Equivalent to calling hide().
* @hide
*/
public static final int SURFACE_HIDDEN = 0x01;
private final CloseGuard mCloseGuard = CloseGuard.get();
private String mName;
// Note: These fields are accessed by native code.
// The mSurfaceControl will only be present for Surfaces used by the window
// server or system processes. When this class is parceled we defer to the
// mSurfaceControl to do the parceling. Otherwise we parcel the
// mNativeSurface.
private int mNativeSurface; // Surface*
private int mNativeSurfaceControl; // SurfaceControl*
private int mGenerationId; // incremented each time mNativeSurface changes
private final Canvas mCanvas = new CompatibleCanvas();
private int mCanvasSaveCount; // Canvas save count at time of lockCanvas()
// The Translator for density compatibility mode. This is used for scaling
// the canvas to perform the appropriate density transformation.
private Translator mCompatibilityTranslator;
// A matrix to scale the matrix set by application. This is set to null for
// non compatibility mode.
private Matrix mCompatibleMatrix;
private native void nativeCreate(SurfaceSession session, String name,
int w, int h, int format, int flags)
throws OutOfResourcesException;
private native void nativeCreateFromSurfaceTexture(SurfaceTexture surfaceTexture)
throws OutOfResourcesException;
private native void nativeRelease();
private native void nativeDestroy();
private native boolean nativeIsValid();
private native int nativeGetIdentity();
private native boolean nativeIsConsumerRunningBehind();
private native Canvas nativeLockCanvas(Rect dirty);
private native void nativeUnlockCanvasAndPost(Canvas canvas);
private static native Bitmap nativeScreenshot(IBinder displayToken,
int width, int height, int minLayer, int maxLayer, boolean allLayers);
private static native void nativeOpenTransaction();
private static native void nativeCloseTransaction();
private native void nativeSetLayer(int zorder);
private native void nativeSetPosition(float x, float y);
private native void nativeSetSize(int w, int h);
private native void nativeSetTransparentRegionHint(Region region);
private native void nativeSetAlpha(float alpha);
private native void nativeSetMatrix(float dsdx, float dtdx, float dsdy, float dtdy);
private native void nativeSetFlags(int flags, int mask);
private native void nativeSetWindowCrop(Rect crop);
private native void nativeSetLayerStack(int layerStack);
private static native IBinder nativeGetBuiltInDisplay(int physicalDisplayId);
private static native IBinder nativeCreateDisplay(String name);
private static native void nativeSetDisplaySurface(
IBinder displayToken, SurfaceTexture surfaceTexture);
private static native void nativeSetDisplayLayerStack(
IBinder displayToken, int layerStack);
private static native void nativeSetDisplayOrientation(
IBinder displayToken, int orientation);
private static native void nativeSetDisplayViewport(
IBinder displayToken, Rect viewport);
private static native void nativeSetDisplayFrame(
IBinder displayToken, Rect frame);
private static native boolean nativeGetDisplayInfo(
IBinder displayToken, PhysicalDisplayInfo outInfo);
private native void nativeCopyFrom(Surface other);
private native void nativeTransferFrom(Surface other);
private native void nativeReadFromParcel(Parcel source);
private native void nativeWriteToParcel(Parcel dest);
/**
* Create an empty surface, which will later be filled in by readFromParcel().
* @hide
*/
public Surface() {
checkHeadless();
mCloseGuard.open("release");
}
/**
* Create a surface with a name.
*
* The surface creation flags specify what kind of surface to create and
* certain options such as whether the surface can be assumed to be opaque
* and whether it should be initially hidden. Surfaces should always be
* created with the {@link #HIDDEN} flag set to ensure that they are not
* made visible prematurely before all of the surface's properties have been
* configured.
*
* Good practice is to first create the surface with the {@link #HIDDEN} flag
* specified, open a transaction, set the surface layer, layer stack, alpha,
* and position, call {@link #show} if appropriate, and close the transaction.
*
* @param session The surface session, must not be null.
* @param name The surface name, must not be null.
* @param w The surface initial width.
* @param h The surface initial height.
* @param flags The surface creation flags. Should always include {@link #HIDDEN}
* in the creation flags.
* @hide
*/
public Surface(SurfaceSession session,
String name, int w, int h, int format, int flags)
throws OutOfResourcesException {
if (session == null) {
throw new IllegalArgumentException("session must not be null");
}
if (name == null) {
throw new IllegalArgumentException("name must not be null");
}
if ((flags & HIDDEN) == 0) {
Log.w(TAG, "Surfaces should always be created with the HIDDEN flag set "
+ "to ensure that they are not made visible prematurely before "
+ "all of the surface's properties have been configured. "
+ "Set the other properties and make the surface visible within "
+ "a transaction. New surface name: " + name,
new Throwable());
}
checkHeadless();
mName = name;
nativeCreate(session, name, w, h, format, flags);
mCloseGuard.open("release");
}
/**
* Create Surface from a {@link SurfaceTexture}.
*
* Images drawn to the Surface will be made available to the {@link
* SurfaceTexture}, which can attach them to an OpenGL ES texture via {@link
* SurfaceTexture#updateTexImage}.
*
* @param surfaceTexture The {@link SurfaceTexture} that is updated by this
* Surface.
*/
public Surface(SurfaceTexture surfaceTexture) {
if (surfaceTexture == null) {
throw new IllegalArgumentException("surfaceTexture must not be null");
}
checkHeadless();
mName = surfaceTexture.toString();
try {
nativeCreateFromSurfaceTexture(surfaceTexture);
} catch (OutOfResourcesException ex) {
// We can't throw OutOfResourcesException because it would be an API change.
throw new RuntimeException(ex);
}
mCloseGuard.open("release");
}
@Override
protected void finalize() throws Throwable {
try {
if (mCloseGuard != null) {
mCloseGuard.warnIfOpen();
}
nativeRelease();
} finally {
super.finalize();
}
}
/**
* Release the local reference to the server-side surface.
* Always call release() when you're done with a Surface.
* This will make the surface invalid.
*/
public void release() {
nativeRelease();
mCloseGuard.close();
}
/**
* Free all server-side state associated with this surface and
* release this object's reference. This method can only be
* called from the process that created the service.
* @hide
*/
public void destroy() {
nativeDestroy();
mCloseGuard.close();
}
/**
* Returns true if this object holds a valid surface.
*
* @return True if it holds a physical surface, so lockCanvas() will succeed.
* Otherwise returns false.
*/
public boolean isValid() {
return nativeIsValid();
}
/**
* Gets the generation number of this surface, incremented each time
* the native surface contained within this object changes.
*
* @return The current generation number.
* @hide
*/
public int getGenerationId() {
return mGenerationId;
}
/**
* Returns true if the consumer of this Surface is running behind the producer.
*
* @return True if the consumer is more than one buffer ahead of the producer.
* @hide
*/
public boolean isConsumerRunningBehind() {
return nativeIsConsumerRunningBehind();
}
/**
* Gets a {@link Canvas} for drawing into this surface.
*
* After drawing into the provided {@link Canvas}, the caller should
* invoke {@link #unlockCanvasAndPost} to post the new contents to the surface.
*
* @param dirty A rectangle that represents the dirty region that the caller wants
* to redraw. This function may choose to expand the dirty rectangle if for example
* the surface has been resized or if the previous contents of the surface were
* not available. The caller should redraw the entire dirty region as represented
* by the contents of the dirty rect upon return from this function.
* The caller may also pass <code>null</code> instead, in the case where the
* entire surface should be redrawn.
* @return A canvas for drawing into the surface.
*/
public Canvas lockCanvas(Rect dirty)
throws OutOfResourcesException, IllegalArgumentException {
return nativeLockCanvas(dirty);
}
/**
* Posts the new contents of the {@link Canvas} to the surface and
* releases the {@link Canvas}.
*
* @param canvas The canvas previously obtained from {@link #lockCanvas}.
*/
public void unlockCanvasAndPost(Canvas canvas) {
nativeUnlockCanvasAndPost(canvas);
}
/**
* @deprecated This API has been removed and is not supported. Do not use.
*/
@Deprecated
public void unlockCanvas(Canvas canvas) {
throw new UnsupportedOperationException();
}
/**
* Sets the translator used to scale canvas's width/height in compatibility
* mode.
*/
void setCompatibilityTranslator(Translator translator) {
if (translator != null) {
float appScale = translator.applicationScale;
mCompatibleMatrix = new Matrix();
mCompatibleMatrix.setScale(appScale, appScale);
}
}
/**
* Like {@link #screenshot(int, int, int, int)} but includes all
* Surfaces in the screenshot.
*
* @hide
*/
public static Bitmap screenshot(int width, int height) {
// TODO: should take the display as a parameter
IBinder displayToken = getBuiltInDisplay(BUILT_IN_DISPLAY_ID_MAIN);
return nativeScreenshot(displayToken, width, height, 0, 0, true);
}
/**
* Copy the current screen contents into a bitmap and return it.
*
* @param width The desired width of the returned bitmap; the raw
* screen will be scaled down to this size.
* @param height The desired height of the returned bitmap; the raw
* screen will be scaled down to this size.
* @param minLayer The lowest (bottom-most Z order) surface layer to
* include in the screenshot.
* @param maxLayer The highest (top-most Z order) surface layer to
* include in the screenshot.
* @return Returns a Bitmap containing the screen contents, or null
* if an error occurs.
*
* @hide
*/
public static Bitmap screenshot(int width, int height, int minLayer, int maxLayer) {
// TODO: should take the display as a parameter
IBinder displayToken = getBuiltInDisplay(BUILT_IN_DISPLAY_ID_MAIN);
return nativeScreenshot(displayToken, width, height, minLayer, maxLayer, false);
}
/*
* set surface parameters.
* needs to be inside open/closeTransaction block
*/
/** start a transaction @hide */
public static void openTransaction() {
nativeOpenTransaction();
}
/** end a transaction @hide */
public static void closeTransaction() {
nativeCloseTransaction();
}
/** @hide */
public void setLayer(int zorder) {
nativeSetLayer(zorder);
}
/** @hide */
public void setPosition(int x, int y) {
nativeSetPosition((float)x, (float)y);
}
/** @hide */
public void setPosition(float x, float y) {
nativeSetPosition(x, y);
}
/** @hide */
public void setSize(int w, int h) {
nativeSetSize(w, h);
}
/** @hide */
public void hide() {
nativeSetFlags(SURFACE_HIDDEN, SURFACE_HIDDEN);
}
/** @hide */
public void show() {
nativeSetFlags(0, SURFACE_HIDDEN);
}
/** @hide */
public void setTransparentRegionHint(Region region) {
nativeSetTransparentRegionHint(region);
}
/** @hide */
public void setAlpha(float alpha) {
nativeSetAlpha(alpha);
}
/** @hide */
public void setMatrix(float dsdx, float dtdx, float dsdy, float dtdy) {
nativeSetMatrix(dsdx, dtdx, dsdy, dtdy);
}
/** @hide */
public void setFlags(int flags, int mask) {
nativeSetFlags(flags, mask);
}
/** @hide */
public void setWindowCrop(Rect crop) {
nativeSetWindowCrop(crop);
}
/** @hide */
public void setLayerStack(int layerStack) {
nativeSetLayerStack(layerStack);
}
/** @hide */
public static IBinder getBuiltInDisplay(int builtInDisplayId) {
return nativeGetBuiltInDisplay(builtInDisplayId);
}
/** @hide */
public static IBinder createDisplay(String name) {
if (name == null) {
throw new IllegalArgumentException("name must not be null");
}
return nativeCreateDisplay(name);
}
/** @hide */
public static void setDisplaySurface(IBinder displayToken, SurfaceTexture surfaceTexture) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
nativeSetDisplaySurface(displayToken, surfaceTexture);
}
/** @hide */
public static void setDisplayLayerStack(IBinder displayToken, int layerStack) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
nativeSetDisplayLayerStack(displayToken, layerStack);
}
/** @hide */
public static void setDisplayOrientation(IBinder displayToken, int orientation) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
nativeSetDisplayOrientation(displayToken, orientation);
}
/** @hide */
public static void setDisplayViewport(IBinder displayToken, Rect viewport) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
if (viewport == null) {
throw new IllegalArgumentException("viewport must not be null");
}
nativeSetDisplayViewport(displayToken, viewport);
}
/** @hide */
public static void setDisplayFrame(IBinder displayToken, Rect frame) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
if (frame == null) {
throw new IllegalArgumentException("frame must not be null");
}
nativeSetDisplayFrame(displayToken, frame);
}
/** @hide */
public static boolean getDisplayInfo(IBinder displayToken, PhysicalDisplayInfo outInfo) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
if (outInfo == null) {
throw new IllegalArgumentException("outInfo must not be null");
}
return nativeGetDisplayInfo(displayToken, outInfo);
}
/**
* Copy another surface to this one. This surface now holds a reference
* to the same data as the original surface, and is -not- the owner.
* This is for use by the window manager when returning a window surface
* back from a client, converting it from the representation being managed
* by the window manager to the representation the client uses to draw
* in to it.
* @hide
*/
public void copyFrom(Surface other) {
if (other == null) {
throw new IllegalArgumentException("other must not be null");
}
if (other != this) {
nativeCopyFrom(other);
}
}
/**
* Transfer the native state from 'other' to this surface, releasing it
* from 'other'. This is for use in the client side for drawing into a
* surface; not guaranteed to work on the window manager side.
* This is for use by the client to move the underlying surface from
* one Surface object to another, in particular in SurfaceFlinger.
* @hide.
*/
public void transferFrom(Surface other) {
if (other == null) {
throw new IllegalArgumentException("other must not be null");
}
if (other != this) {
nativeTransferFrom(other);
}
}
@Override
public int describeContents() {
return 0;
}
public void readFromParcel(Parcel source) {
if (source == null) {
throw new IllegalArgumentException("source must not be null");
}
mName = source.readString();
nativeReadFromParcel(source);
}
@Override
public void writeToParcel(Parcel dest, int flags) {
if (dest == null) {
throw new IllegalArgumentException("dest must not be null");
}
dest.writeString(mName);
nativeWriteToParcel(dest);
if ((flags & Parcelable.PARCELABLE_WRITE_RETURN_VALUE) != 0) {
release();
}
}
@Override
public String toString() {
return "Surface(name=" + mName + ", identity=" + nativeGetIdentity() + ")";
}
private static void checkHeadless() {
if (HEADLESS) {
throw new UnsupportedOperationException("Device is headless");
}
}
/**
* Exception thrown when a surface couldn't be created or resized.
*/
public static class OutOfResourcesException extends Exception {
public OutOfResourcesException() {
}
public OutOfResourcesException(String name) {
super(name);
}
}
/**
* Describes the properties of a physical display.
* @hide
*/
public static final class PhysicalDisplayInfo {
// TODO: redesign this
public int width;
public int height;
public float refreshRate;
public float density;
public float xDpi;
public float yDpi;
}
/**
* A Canvas class that can handle the compatibility mode.
* This does two things differently.
* <ul>
* <li>Returns the width and height of the target metrics, rather than
* native. For example, the canvas returns 320x480 even if an app is running
* in WVGA high density.
* <li>Scales the matrix in setMatrix by the application scale, except if
* the matrix looks like obtained from getMatrix. This is a hack to handle
* the case that an application uses getMatrix to keep the original matrix,
* set matrix of its own, then set the original matrix back. There is no
* perfect solution that works for all cases, and there are a lot of cases
* that this model does not work, but we hope this works for many apps.
* </ul>
*/
private final class CompatibleCanvas extends Canvas {
// A temp matrix to remember what an application obtained via {@link getMatrix}
private Matrix mOrigMatrix = null;
@Override
public int getWidth() {
int w = super.getWidth();
if (mCompatibilityTranslator != null) {
w = (int)(w * mCompatibilityTranslator.applicationInvertedScale + .5f);
}
return w;
}
@Override
public int getHeight() {
int h = super.getHeight();
if (mCompatibilityTranslator != null) {
h = (int)(h * mCompatibilityTranslator.applicationInvertedScale + .5f);
}
return h;
}
@Override
public void setMatrix(Matrix matrix) {
if (mCompatibleMatrix == null || mOrigMatrix == null || mOrigMatrix.equals(matrix)) {
// don't scale the matrix if it's not compatibility mode, or
// the matrix was obtained from getMatrix.
super.setMatrix(matrix);
} else {
Matrix m = new Matrix(mCompatibleMatrix);
m.preConcat(matrix);
super.setMatrix(m);
}
}
@Override
public void getMatrix(Matrix m) {
super.getMatrix(m);
if (mOrigMatrix == null) {
mOrigMatrix = new Matrix();
}
mOrigMatrix.set(m);
}
}
}
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