services/surfaceflinger/Layer.cpp - android_frameworks_native - Gitiles

 /*
  * 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.
  */

 #include <stdlib.h>
 #include <stdint.h>
 #include <sys/types.h>

 #include <cutils/compiler.h>
 #include <cutils/native_handle.h>
 #include <cutils/properties.h>

 #include <utils/Errors.h>
 #include <utils/Log.h>
 #include <utils/StopWatch.h>

 #include <ui/GraphicBuffer.h>
 #include <ui/PixelFormat.h>

 #include <surfaceflinger/Surface.h>

 #include "clz.h"
 #include "DisplayHardware/DisplayHardware.h"
 #include "DisplayHardware/HWComposer.h"
 #include "GLExtensions.h"
 #include "Layer.h"
 #include "SurfaceFlinger.h"
 #include "SurfaceTextureLayer.h"

 #define DEBUG_RESIZE    0


 namespace android {

 // ---------------------------------------------------------------------------

 Layer::Layer(SurfaceFlinger* flinger,
         DisplayID display, const sp<Client>& client)
     :   LayerBaseClient(flinger, display, client),
         mTextureName(-1U),
         mQueuedFrames(0),
         mCurrentTransform(0),
         mCurrentScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
         mCurrentOpacity(true),
         mFormat(PIXEL_FORMAT_NONE),
         mGLExtensions(GLExtensions::getInstance()),
         mOpaqueLayer(true),
         mNeedsDithering(false),
         mSecure(false),
         mProtectedByApp(false)
 {
     mCurrentCrop.makeInvalid();
     glGenTextures(1, &mTextureName);
 }

 void Layer::onFirstRef()
 {
     LayerBaseClient::onFirstRef();

     struct FrameQueuedListener : public SurfaceTexture::FrameAvailableListener {
         FrameQueuedListener(Layer* layer) : mLayer(layer) { }
     private:
         wp<Layer> mLayer;
         virtual void onFrameAvailable() {
             sp<Layer> that(mLayer.promote());
             if (that != 0) {
                 that->onFrameQueued();
             }
         }
     };
     mSurfaceTexture = new SurfaceTextureLayer(mTextureName, this);
     mSurfaceTexture->setFrameAvailableListener(new FrameQueuedListener(this));
     mSurfaceTexture->setSynchronousMode(true);
     mSurfaceTexture->setBufferCountServer(2);
 }

 Layer::~Layer()
 {
     class MessageDestroyGLState : public MessageBase {
         GLuint texture;
     public:
         MessageDestroyGLState(GLuint texture) : texture(texture) { }
         virtual bool handler() {
             glDeleteTextures(1, &texture);
             return true;
         }
     };
     mFlinger->postMessageAsync( new MessageDestroyGLState(mTextureName) );
 }

 void Layer::onFrameQueued() {
     android_atomic_inc(&mQueuedFrames);
     mFlinger->signalEvent();
 }

 // called with SurfaceFlinger::mStateLock as soon as the layer is entered
 // in the purgatory list
 void Layer::onRemoved()
 {
     mSurfaceTexture->abandon();
 }

 void Layer::setName(const String8& name) {
     LayerBase::setName(name);
     mSurfaceTexture->setName(name);
 }

 sp<ISurface> Layer::createSurface()
 {
     class BSurface : public BnSurface, public LayerCleaner {
         wp<const Layer> mOwner;
         virtual sp<ISurfaceTexture> getSurfaceTexture() const {
             sp<ISurfaceTexture> res;
             sp<const Layer> that( mOwner.promote() );
             if (that != NULL) {
                 res = that->mSurfaceTexture;
             }
             return res;
         }
     public:
         BSurface(const sp<SurfaceFlinger>& flinger,
                 const sp<Layer>& layer)
             : LayerCleaner(flinger, layer), mOwner(layer) { }
     };
     sp<ISurface> sur(new BSurface(mFlinger, this));
     return sur;
 }

 wp<IBinder> Layer::getSurfaceTextureBinder() const
 {
     return mSurfaceTexture->asBinder();
 }

 status_t Layer::setBuffers( uint32_t w, uint32_t h,
                             PixelFormat format, uint32_t flags)
 {
     // this surfaces pixel format
     PixelFormatInfo info;
     status_t err = getPixelFormatInfo(format, &info);
     if (err) return err;

     // the display's pixel format
     const DisplayHardware& hw(graphicPlane(0).displayHardware());
     uint32_t const maxSurfaceDims = min(
             hw.getMaxTextureSize(), hw.getMaxViewportDims());

     // never allow a surface larger than what our underlying GL implementation
     // can handle.
     if ((uint32_t(w)>maxSurfaceDims) || (uint32_t(h)>maxSurfaceDims)) {
         return BAD_VALUE;
     }

     PixelFormatInfo displayInfo;
     getPixelFormatInfo(hw.getFormat(), &displayInfo);
     const uint32_t hwFlags = hw.getFlags();

     mFormat = format;

     mSecure = (flags & ISurfaceComposer::eSecure) ? true : false;
     mProtectedByApp = (flags & ISurfaceComposer::eProtectedByApp) ? true : false;
     mOpaqueLayer = (flags & ISurfaceComposer::eOpaque);
     mCurrentOpacity = getOpacityForFormat(format);

     mSurfaceTexture->setDefaultBufferSize(w, h);
     mSurfaceTexture->setDefaultBufferFormat(format);

     // we use the red index
     int displayRedSize = displayInfo.getSize(PixelFormatInfo::INDEX_RED);
     int layerRedsize = info.getSize(PixelFormatInfo::INDEX_RED);
     mNeedsDithering = layerRedsize > displayRedSize;

     return NO_ERROR;
 }

 void Layer::setGeometry(hwc_layer_t* hwcl)
 {
     LayerBaseClient::setGeometry(hwcl);

     hwcl->flags &= ~HWC_SKIP_LAYER;

     // we can't do alpha-fade with the hwc HAL
     const State& s(drawingState());
     if (s.alpha < 0xFF) {
         hwcl->flags = HWC_SKIP_LAYER;
     }

     /*
      * Transformations are applied in this order:
      * 1) buffer orientation/flip/mirror
      * 2) state transformation (window manager)
      * 3) layer orientation (screen orientation)
      * mTransform is already the composition of (2) and (3)
      * (NOTE: the matrices are multiplied in reverse order)
      */

     const Transform bufferOrientation(mCurrentTransform);
     const Transform tr(mTransform * bufferOrientation);

     // this gives us only the "orientation" component of the transform
     const uint32_t finalTransform = tr.getOrientation();

     // we can only handle simple transformation
     if (finalTransform & Transform::ROT_INVALID) {
         hwcl->flags = HWC_SKIP_LAYER;
     } else {
         hwcl->transform = finalTransform;
     }

     if (isCropped()) {
         hwcl->sourceCrop.left   = mCurrentCrop.left;
         hwcl->sourceCrop.top    = mCurrentCrop.top;
         hwcl->sourceCrop.right  = mCurrentCrop.right;
         hwcl->sourceCrop.bottom = mCurrentCrop.bottom;
     } else {
         const sp<GraphicBuffer>& buffer(mActiveBuffer);
         hwcl->sourceCrop.left   = 0;
         hwcl->sourceCrop.top    = 0;
         if (buffer != NULL) {
             hwcl->sourceCrop.right  = buffer->width;
             hwcl->sourceCrop.bottom = buffer->height;
         } else {
             hwcl->sourceCrop.right  = mTransformedBounds.width();
             hwcl->sourceCrop.bottom = mTransformedBounds.height();
         }
     }
 }

 void Layer::setPerFrameData(hwc_layer_t* hwcl) {
     const sp<GraphicBuffer>& buffer(mActiveBuffer);
     if (buffer == NULL) {
         // this can happen if the client never drew into this layer yet,
         // or if we ran out of memory. In that case, don't let
         // HWC handle it.
         hwcl->flags |= HWC_SKIP_LAYER;
         hwcl->handle = NULL;
     } else {
         hwcl->handle = buffer->handle;
     }
 }

 void Layer::onDraw(const Region& clip) const
 {
     if (CC_UNLIKELY(mActiveBuffer == 0)) {
         // the texture has not been created yet, this Layer has
         // in fact never been drawn into. This happens frequently with
         // SurfaceView because the WindowManager can't know when the client
         // has drawn the first time.

         // If there is nothing under us, we paint the screen in black, otherwise
         // we just skip this update.

         // figure out if there is something below us
         Region under;
         const SurfaceFlinger::LayerVector& drawingLayers(
                 mFlinger->mDrawingState.layersSortedByZ);
         const size_t count = drawingLayers.size();
         for (size_t i=0 ; i<count ; ++i) {
             const sp<LayerBase>& layer(drawingLayers[i]);
             if (layer.get() == static_cast<LayerBase const*>(this))
                 break;
             under.orSelf(layer->visibleRegionScreen);
         }
         // if not everything below us is covered, we plug the holes!
         Region holes(clip.subtract(under));
         if (!holes.isEmpty()) {
             clearWithOpenGL(holes, 0, 0, 0, 1);
         }
         return;
     }

     GLenum target = GL_TEXTURE_EXTERNAL_OES;
     if (!isProtected()) {
         glBindTexture(target, mTextureName);
         if (getFiltering() || needsFiltering() || isFixedSize() || isCropped()) {
             // TODO: we could be more subtle with isFixedSize()
             glTexParameterx(target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
             glTexParameterx(target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
         } else {
             glTexParameterx(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
             glTexParameterx(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
         }
         glEnable(target);
         glMatrixMode(GL_TEXTURE);
         glLoadMatrixf(mTextureMatrix);
         glMatrixMode(GL_MODELVIEW);
     } else {
         target = GL_TEXTURE_2D;
         glBindTexture(target, mFlinger->getProtectedTexName());
         glEnable(target);
         glMatrixMode(GL_TEXTURE);
         glLoadIdentity();
         glMatrixMode(GL_MODELVIEW);
     }

     drawWithOpenGL(clip);

     glDisable(target);
 }

 // As documented in libhardware header, formats in the range
 // 0x100 - 0x1FF are specific to the HAL implementation, and
 // are known to have no alpha channel
 // TODO: move definition for device-specific range into
 // hardware.h, instead of using hard-coded values here.
 #define HARDWARE_IS_DEVICE_FORMAT(f) ((f) >= 0x100 && (f) <= 0x1FF)

 bool Layer::getOpacityForFormat(uint32_t format)
 {
     if (HARDWARE_IS_DEVICE_FORMAT(format)) {
         return true;
     }
     PixelFormatInfo info;
     status_t err = getPixelFormatInfo(PixelFormat(format), &info);
     // in case of error (unknown format), we assume no blending
     return (err || info.h_alpha <= info.l_alpha);
 }


 bool Layer::isOpaque() const
 {
     // if we don't have a buffer yet, we're translucent regardless of the
     // layer's opaque flag.
     if (mActiveBuffer == 0) {
         return false;
     }

     // if the layer has the opaque flag, then we're always opaque,
     // otherwise we use the current buffer's format.
     return mOpaqueLayer || mCurrentOpacity;
 }

 bool Layer::isProtected() const
 {
     const sp<GraphicBuffer>& activeBuffer(mActiveBuffer);
     return (activeBuffer != 0) &&
             (activeBuffer->getUsage() & GRALLOC_USAGE_PROTECTED);
 }

 uint32_t Layer::doTransaction(uint32_t flags)
 {
     const Layer::State& front(drawingState());
     const Layer::State& temp(currentState());

     const bool sizeChanged = (front.requested_w != temp.requested_w) ||
             (front.requested_h != temp.requested_h);

     if (sizeChanged) {
         // the size changed, we need to ask our client to request a new buffer
         LOGD_IF(DEBUG_RESIZE,
                 "doTransaction: "
                 "resize (layer=%p), requested (%dx%d), drawing (%d,%d), "
                 "scalingMode=%d",
                 this,
                 int(temp.requested_w), int(temp.requested_h),
                 int(front.requested_w), int(front.requested_h),
                 mCurrentScalingMode);

         if (!isFixedSize()) {
             // we're being resized and there is a freeze display request,
             // acquire a freeze lock, so that the screen stays put
             // until we've redrawn at the new size; this is to avoid
             // glitches upon orientation changes.
             if (mFlinger->hasFreezeRequest()) {
                 // if the surface is hidden, don't try to acquire the
                 // freeze lock, since hidden surfaces may never redraw
                 if (!(front.flags & ISurfaceComposer::eLayerHidden)) {
                     mFreezeLock = mFlinger->getFreezeLock();
                 }
             }

             // this will make sure LayerBase::doTransaction doesn't update
             // the drawing state's size
             Layer::State& editDraw(mDrawingState);
             editDraw.requested_w = temp.requested_w;
             editDraw.requested_h = temp.requested_h;
         }

         // record the new size, form this point on, when the client request
         // a buffer, it'll get the new size.
         mSurfaceTexture->setDefaultBufferSize(temp.requested_w,
                 temp.requested_h);
     }

     if (temp.sequence != front.sequence) {
         if (temp.flags & ISurfaceComposer::eLayerHidden || temp.alpha == 0) {
             // this surface is now hidden, so it shouldn't hold a freeze lock
             // (it may never redraw, which is fine if it is hidden)
             mFreezeLock.clear();
         }
     }

     return LayerBase::doTransaction(flags);
 }

 bool Layer::isFixedSize() const {
     return mCurrentScalingMode != NATIVE_WINDOW_SCALING_MODE_FREEZE;
 }

 bool Layer::isCropped() const {
     return !mCurrentCrop.isEmpty();
 }

 // ----------------------------------------------------------------------------
 // pageflip handling...
 // ----------------------------------------------------------------------------

 void Layer::lockPageFlip(bool& recomputeVisibleRegions)
 {
     if (mQueuedFrames > 0) {
         // Capture the old state of the layer for comparisons later
         const bool oldOpacity = isOpaque();
         sp<GraphicBuffer> oldActiveBuffer = mActiveBuffer;

         // signal another event if we have more frames pending
         if (android_atomic_dec(&mQueuedFrames) > 1) {
             mFlinger->signalEvent();
         }

         if (mSurfaceTexture->updateTexImage() < NO_ERROR) {
             // something happened!
             recomputeVisibleRegions = true;
             return;
         }

         // update the active buffer
         mActiveBuffer = mSurfaceTexture->getCurrentBuffer();

         const Rect crop(mSurfaceTexture->getCurrentCrop());
         const uint32_t transform(mSurfaceTexture->getCurrentTransform());
         const uint32_t scalingMode(mSurfaceTexture->getCurrentScalingMode());
         if ((crop != mCurrentCrop) ||
             (transform != mCurrentTransform) ||
             (scalingMode != mCurrentScalingMode))
         {
             mCurrentCrop = crop;
             mCurrentTransform = transform;
             mCurrentScalingMode = scalingMode;
             mFlinger->invalidateHwcGeometry();
         }

         GLfloat textureMatrix[16];
         mSurfaceTexture->getTransformMatrix(textureMatrix);
         if (memcmp(textureMatrix, mTextureMatrix, sizeof(textureMatrix))) {
             memcpy(mTextureMatrix, textureMatrix, sizeof(textureMatrix));
             mFlinger->invalidateHwcGeometry();
         }

         uint32_t bufWidth  = mActiveBuffer->getWidth();
         uint32_t bufHeight = mActiveBuffer->getHeight();
         if (oldActiveBuffer != NULL) {
             if (bufWidth != uint32_t(oldActiveBuffer->width) ||
                 bufHeight != uint32_t(oldActiveBuffer->height)) {
                 mFlinger->invalidateHwcGeometry();
             }
         }

         mCurrentOpacity = getOpacityForFormat(mActiveBuffer->format);
         if (oldOpacity != isOpaque()) {
             recomputeVisibleRegions = true;
         }

         glTexParameterx(GL_TEXTURE_EXTERNAL_OES, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameterx(GL_TEXTURE_EXTERNAL_OES, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

         // update the layer size and release freeze-lock
         const Layer::State& front(drawingState());

         // FIXME: mPostedDirtyRegion = dirty & bounds
         mPostedDirtyRegion.set(front.w, front.h);

         if ((front.w != front.requested_w) ||
             (front.h != front.requested_h))
         {
             // check that we received a buffer of the right size
             // (Take the buffer's orientation into account)
             if (mCurrentTransform & Transform::ROT_90) {
                 swap(bufWidth, bufHeight);
             }

             if (isFixedSize() ||
                     (bufWidth == front.requested_w &&
                     bufHeight == front.requested_h))
             {
                 // Here we pretend the transaction happened by updating the
                 // current and drawing states. Drawing state is only accessed
                 // in this thread, no need to have it locked
                 Layer::State& editDraw(mDrawingState);
                 editDraw.w = editDraw.requested_w;
                 editDraw.h = editDraw.requested_h;

                 // We also need to update the current state so that we don't
                 // end-up doing too much work during the next transaction.
                 // NOTE: We actually don't need hold the transaction lock here
                 // because State::w and State::h are only accessed from
                 // this thread
                 Layer::State& editTemp(currentState());
                 editTemp.w = editDraw.w;
                 editTemp.h = editDraw.h;

                 // recompute visible region
                 recomputeVisibleRegions = true;

                 // we now have the correct size, unfreeze the screen
                 mFreezeLock.clear();
             }

             LOGD_IF(DEBUG_RESIZE,
                     "lockPageFlip : "
                     "       (layer=%p), buffer (%ux%u, tr=%02x), "
                     "requested (%dx%d)",
                     this,
                     bufWidth, bufHeight, mCurrentTransform,
                     front.requested_w, front.requested_h);
         }
     }
 }

 void Layer::unlockPageFlip(
         const Transform& planeTransform, Region& outDirtyRegion)
 {
     Region dirtyRegion(mPostedDirtyRegion);
     if (!dirtyRegion.isEmpty()) {
         mPostedDirtyRegion.clear();
         // The dirty region is given in the layer's coordinate space
         // transform the dirty region by the surface's transformation
         // and the global transformation.
         const Layer::State& s(drawingState());
         const Transform tr(planeTransform * s.transform);
         dirtyRegion = tr.transform(dirtyRegion);

         // At this point, the dirty region is in screen space.
         // Make sure it's constrained by the visible region (which
         // is in screen space as well).
         dirtyRegion.andSelf(visibleRegionScreen);
         outDirtyRegion.orSelf(dirtyRegion);
     }
     if (visibleRegionScreen.isEmpty()) {
         // an invisible layer should not hold a freeze-lock
         // (because it may never be updated and therefore never release it)
         mFreezeLock.clear();
     }
 }

 void Layer::dump(String8& result, char* buffer, size_t SIZE) const
 {
     LayerBaseClient::dump(result, buffer, SIZE);

     sp<const GraphicBuffer> buf0(mActiveBuffer);
     uint32_t w0=0, h0=0, s0=0, f0=0;
     if (buf0 != 0) {
         w0 = buf0->getWidth();
         h0 = buf0->getHeight();
         s0 = buf0->getStride();
         f0 = buf0->format;
     }
     snprintf(buffer, SIZE,
             "      "
             "format=%2d, activeBuffer=[%4ux%4u:%4u,%3X],"
             " freezeLock=%p, transform-hint=0x%02x, queued-frames=%d\n",
             mFormat, w0, h0, s0,f0,
             getFreezeLock().get(), getTransformHint(), mQueuedFrames);

     result.append(buffer);

     if (mSurfaceTexture != 0) {
         mSurfaceTexture->dump(result, "            ", buffer, SIZE);
     }
 }

 uint32_t Layer::getEffectiveUsage(uint32_t usage) const
 {
     // TODO: should we do something special if mSecure is set?
     if (mProtectedByApp) {
         // need a hardware-protected path to external video sink
         usage |= GraphicBuffer::USAGE_PROTECTED;
     }
     usage |= GraphicBuffer::USAGE_HW_COMPOSER;
     return usage;
 }

 uint32_t Layer::getTransformHint() const {
     uint32_t orientation = 0;
     if (!mFlinger->mDebugDisableTransformHint) {
         orientation = getPlaneOrientation();
         if (orientation & Transform::ROT_INVALID) {
             orientation = 0;
         }
     }
     return orientation;
 }

 // ---------------------------------------------------------------------------


 }; // namespace android
	/*
	* 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.
	*/

	#include <stdlib.h>
	#include <stdint.h>
	#include <sys/types.h>

	#include <cutils/compiler.h>
	#include <cutils/native_handle.h>
	#include <cutils/properties.h>

	#include <utils/Errors.h>
	#include <utils/Log.h>
	#include <utils/StopWatch.h>

	#include <ui/GraphicBuffer.h>
	#include <ui/PixelFormat.h>

	#include <surfaceflinger/Surface.h>

	#include "clz.h"
	#include "DisplayHardware/DisplayHardware.h"
	#include "DisplayHardware/HWComposer.h"
	#include "GLExtensions.h"
	#include "Layer.h"
	#include "SurfaceFlinger.h"
	#include "SurfaceTextureLayer.h"

	#define DEBUG_RESIZE 0


	namespace android {

	// ---------------------------------------------------------------------------

	Layer::Layer(SurfaceFlinger* flinger,
	DisplayID display, const sp<Client>& client)
	: LayerBaseClient(flinger, display, client),
	mTextureName(-1U),
	mQueuedFrames(0),
	mCurrentTransform(0),
	mCurrentScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
	mCurrentOpacity(true),
	mFormat(PIXEL_FORMAT_NONE),
	mGLExtensions(GLExtensions::getInstance()),
	mOpaqueLayer(true),
	mNeedsDithering(false),
	mSecure(false),
	mProtectedByApp(false)
	{
	mCurrentCrop.makeInvalid();
	glGenTextures(1, &mTextureName);
	}

	void Layer::onFirstRef()
	{
	LayerBaseClient::onFirstRef();

	struct FrameQueuedListener : public SurfaceTexture::FrameAvailableListener {
	FrameQueuedListener(Layer* layer) : mLayer(layer) { }
	private:
	wp<Layer> mLayer;
	virtual void onFrameAvailable() {
	sp<Layer> that(mLayer.promote());
	if (that != 0) {
	that->onFrameQueued();
	}
	}
	};
	mSurfaceTexture = new SurfaceTextureLayer(mTextureName, this);
	mSurfaceTexture->setFrameAvailableListener(new FrameQueuedListener(this));
	mSurfaceTexture->setSynchronousMode(true);
	mSurfaceTexture->setBufferCountServer(2);
	}

	Layer::~Layer()
	{
	class MessageDestroyGLState : public MessageBase {
	GLuint texture;
	public:
	MessageDestroyGLState(GLuint texture) : texture(texture) { }
	virtual bool handler() {
	glDeleteTextures(1, &texture);
	return true;
	}
	};
	mFlinger->postMessageAsync( new MessageDestroyGLState(mTextureName) );
	}

	void Layer::onFrameQueued() {
	android_atomic_inc(&mQueuedFrames);
	mFlinger->signalEvent();
	}

	// called with SurfaceFlinger::mStateLock as soon as the layer is entered
	// in the purgatory list
	void Layer::onRemoved()
	{
	mSurfaceTexture->abandon();
	}

	void Layer::setName(const String8& name) {
	LayerBase::setName(name);
	mSurfaceTexture->setName(name);
	}

	sp<ISurface> Layer::createSurface()
	{
	class BSurface : public BnSurface, public LayerCleaner {
	wp<const Layer> mOwner;
	virtual sp<ISurfaceTexture> getSurfaceTexture() const {
	sp<ISurfaceTexture> res;
	sp<const Layer> that( mOwner.promote() );
	if (that != NULL) {
	res = that->mSurfaceTexture;
	}
	return res;
	}
	public:
	BSurface(const sp<SurfaceFlinger>& flinger,
	const sp<Layer>& layer)
	: LayerCleaner(flinger, layer), mOwner(layer) { }
	};
	sp<ISurface> sur(new BSurface(mFlinger, this));
	return sur;
	}

	wp<IBinder> Layer::getSurfaceTextureBinder() const
	{
	return mSurfaceTexture->asBinder();
	}

	status_t Layer::setBuffers( uint32_t w, uint32_t h,
	PixelFormat format, uint32_t flags)
	{
	// this surfaces pixel format
	PixelFormatInfo info;
	status_t err = getPixelFormatInfo(format, &info);
	if (err) return err;

	// the display's pixel format
	const DisplayHardware& hw(graphicPlane(0).displayHardware());
	uint32_t const maxSurfaceDims = min(
	hw.getMaxTextureSize(), hw.getMaxViewportDims());

	// never allow a surface larger than what our underlying GL implementation
	// can handle.
	if ((uint32_t(w)>maxSurfaceDims) \|\| (uint32_t(h)>maxSurfaceDims)) {
	return BAD_VALUE;
	}

	PixelFormatInfo displayInfo;
	getPixelFormatInfo(hw.getFormat(), &displayInfo);
	const uint32_t hwFlags = hw.getFlags();

	mFormat = format;

	mSecure = (flags & ISurfaceComposer::eSecure) ? true : false;
	mProtectedByApp = (flags & ISurfaceComposer::eProtectedByApp) ? true : false;
	mOpaqueLayer = (flags & ISurfaceComposer::eOpaque);
	mCurrentOpacity = getOpacityForFormat(format);

	mSurfaceTexture->setDefaultBufferSize(w, h);
	mSurfaceTexture->setDefaultBufferFormat(format);

	// we use the red index
	int displayRedSize = displayInfo.getSize(PixelFormatInfo::INDEX_RED);
	int layerRedsize = info.getSize(PixelFormatInfo::INDEX_RED);
	mNeedsDithering = layerRedsize > displayRedSize;

	return NO_ERROR;
	}

	void Layer::setGeometry(hwc_layer_t* hwcl)
	{
	LayerBaseClient::setGeometry(hwcl);

	hwcl->flags &= ~HWC_SKIP_LAYER;

	// we can't do alpha-fade with the hwc HAL
	const State& s(drawingState());
	if (s.alpha < 0xFF) {
	hwcl->flags = HWC_SKIP_LAYER;
	}

	/*
	* Transformations are applied in this order:
	* 1) buffer orientation/flip/mirror
	* 2) state transformation (window manager)
	* 3) layer orientation (screen orientation)
	* mTransform is already the composition of (2) and (3)
	* (NOTE: the matrices are multiplied in reverse order)
	*/

	const Transform bufferOrientation(mCurrentTransform);
	const Transform tr(mTransform * bufferOrientation);

	// this gives us only the "orientation" component of the transform
	const uint32_t finalTransform = tr.getOrientation();

	// we can only handle simple transformation
	if (finalTransform & Transform::ROT_INVALID) {
	hwcl->flags = HWC_SKIP_LAYER;
	} else {
	hwcl->transform = finalTransform;
	}

	if (isCropped()) {
	hwcl->sourceCrop.left = mCurrentCrop.left;
	hwcl->sourceCrop.top = mCurrentCrop.top;
	hwcl->sourceCrop.right = mCurrentCrop.right;
	hwcl->sourceCrop.bottom = mCurrentCrop.bottom;
	} else {
	const sp<GraphicBuffer>& buffer(mActiveBuffer);
	hwcl->sourceCrop.left = 0;
	hwcl->sourceCrop.top = 0;
	if (buffer != NULL) {
	hwcl->sourceCrop.right = buffer->width;
	hwcl->sourceCrop.bottom = buffer->height;
	} else {
	hwcl->sourceCrop.right = mTransformedBounds.width();
	hwcl->sourceCrop.bottom = mTransformedBounds.height();
	}
	}
	}

	void Layer::setPerFrameData(hwc_layer_t* hwcl) {
	const sp<GraphicBuffer>& buffer(mActiveBuffer);
	if (buffer == NULL) {
	// this can happen if the client never drew into this layer yet,
	// or if we ran out of memory. In that case, don't let
	// HWC handle it.
	hwcl->flags \|= HWC_SKIP_LAYER;
	hwcl->handle = NULL;
	} else {
	hwcl->handle = buffer->handle;
	}
	}

	void Layer::onDraw(const Region& clip) const
	{
	if (CC_UNLIKELY(mActiveBuffer == 0)) {
	// the texture has not been created yet, this Layer has
	// in fact never been drawn into. This happens frequently with
	// SurfaceView because the WindowManager can't know when the client
	// has drawn the first time.

	// If there is nothing under us, we paint the screen in black, otherwise
	// we just skip this update.

	// figure out if there is something below us
	Region under;
	const SurfaceFlinger::LayerVector& drawingLayers(
	mFlinger->mDrawingState.layersSortedByZ);
	const size_t count = drawingLayers.size();
	for (size_t i=0 ; i<count ; ++i) {
	const sp<LayerBase>& layer(drawingLayers[i]);
	if (layer.get() == static_cast<LayerBase const*>(this))
	break;
	under.orSelf(layer->visibleRegionScreen);
	}
	// if not everything below us is covered, we plug the holes!
	Region holes(clip.subtract(under));
	if (!holes.isEmpty()) {
	clearWithOpenGL(holes, 0, 0, 0, 1);
	}
	return;
	}

	GLenum target = GL_TEXTURE_EXTERNAL_OES;
	if (!isProtected()) {
	glBindTexture(target, mTextureName);
	if (getFiltering() \|\| needsFiltering() \|\| isFixedSize() \|\| isCropped()) {
	// TODO: we could be more subtle with isFixedSize()
	glTexParameterx(target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexParameterx(target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	} else {
	glTexParameterx(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameterx(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	}
	glEnable(target);
	glMatrixMode(GL_TEXTURE);
	glLoadMatrixf(mTextureMatrix);
	glMatrixMode(GL_MODELVIEW);
	} else {
	target = GL_TEXTURE_2D;
	glBindTexture(target, mFlinger->getProtectedTexName());
	glEnable(target);
	glMatrixMode(GL_TEXTURE);
	glLoadIdentity();
	glMatrixMode(GL_MODELVIEW);
	}

	drawWithOpenGL(clip);

	glDisable(target);
	}

	// As documented in libhardware header, formats in the range
	// 0x100 - 0x1FF are specific to the HAL implementation, and
	// are known to have no alpha channel
	// TODO: move definition for device-specific range into
	// hardware.h, instead of using hard-coded values here.
	#define HARDWARE_IS_DEVICE_FORMAT(f) ((f) >= 0x100 && (f) <= 0x1FF)

	bool Layer::getOpacityForFormat(uint32_t format)
	{
	if (HARDWARE_IS_DEVICE_FORMAT(format)) {
	return true;
	}
	PixelFormatInfo info;
	status_t err = getPixelFormatInfo(PixelFormat(format), &info);
	// in case of error (unknown format), we assume no blending
	return (err \|\| info.h_alpha <= info.l_alpha);
	}


	bool Layer::isOpaque() const
	{
	// if we don't have a buffer yet, we're translucent regardless of the
	// layer's opaque flag.
	if (mActiveBuffer == 0) {
	return false;
	}

	// if the layer has the opaque flag, then we're always opaque,
	// otherwise we use the current buffer's format.
	return mOpaqueLayer \|\| mCurrentOpacity;
	}

	bool Layer::isProtected() const
	{
	const sp<GraphicBuffer>& activeBuffer(mActiveBuffer);
	return (activeBuffer != 0) &&
	(activeBuffer->getUsage() & GRALLOC_USAGE_PROTECTED);
	}

	uint32_t Layer::doTransaction(uint32_t flags)
	{
	const Layer::State& front(drawingState());
	const Layer::State& temp(currentState());

	const bool sizeChanged = (front.requested_w != temp.requested_w) \|\|
	(front.requested_h != temp.requested_h);

	if (sizeChanged) {
	// the size changed, we need to ask our client to request a new buffer
	LOGD_IF(DEBUG_RESIZE,
	"doTransaction: "
	"resize (layer=%p), requested (%dx%d), drawing (%d,%d), "
	"scalingMode=%d",
	this,
	int(temp.requested_w), int(temp.requested_h),
	int(front.requested_w), int(front.requested_h),
	mCurrentScalingMode);

	if (!isFixedSize()) {
	// we're being resized and there is a freeze display request,
	// acquire a freeze lock, so that the screen stays put
	// until we've redrawn at the new size; this is to avoid
	// glitches upon orientation changes.
	if (mFlinger->hasFreezeRequest()) {
	// if the surface is hidden, don't try to acquire the
	// freeze lock, since hidden surfaces may never redraw
	if (!(front.flags & ISurfaceComposer::eLayerHidden)) {
	mFreezeLock = mFlinger->getFreezeLock();
	}
	}

	// this will make sure LayerBase::doTransaction doesn't update
	// the drawing state's size
	Layer::State& editDraw(mDrawingState);
	editDraw.requested_w = temp.requested_w;
	editDraw.requested_h = temp.requested_h;
	}

	// record the new size, form this point on, when the client request
	// a buffer, it'll get the new size.
	mSurfaceTexture->setDefaultBufferSize(temp.requested_w,
	temp.requested_h);
	}

	if (temp.sequence != front.sequence) {
	if (temp.flags & ISurfaceComposer::eLayerHidden \|\| temp.alpha == 0) {
	// this surface is now hidden, so it shouldn't hold a freeze lock
	// (it may never redraw, which is fine if it is hidden)
	mFreezeLock.clear();
	}
	}

	return LayerBase::doTransaction(flags);
	}

	bool Layer::isFixedSize() const {
	return mCurrentScalingMode != NATIVE_WINDOW_SCALING_MODE_FREEZE;
	}

	bool Layer::isCropped() const {
	return !mCurrentCrop.isEmpty();
	}

	// ----------------------------------------------------------------------------
	// pageflip handling...
	// ----------------------------------------------------------------------------

	void Layer::lockPageFlip(bool& recomputeVisibleRegions)
	{
	if (mQueuedFrames > 0) {
	// Capture the old state of the layer for comparisons later
	const bool oldOpacity = isOpaque();
	sp<GraphicBuffer> oldActiveBuffer = mActiveBuffer;

	// signal another event if we have more frames pending
	if (android_atomic_dec(&mQueuedFrames) > 1) {
	mFlinger->signalEvent();
	}

	if (mSurfaceTexture->updateTexImage() < NO_ERROR) {
	// something happened!
	recomputeVisibleRegions = true;
	return;
	}

	// update the active buffer
	mActiveBuffer = mSurfaceTexture->getCurrentBuffer();

	const Rect crop(mSurfaceTexture->getCurrentCrop());
	const uint32_t transform(mSurfaceTexture->getCurrentTransform());
	const uint32_t scalingMode(mSurfaceTexture->getCurrentScalingMode());
	if ((crop != mCurrentCrop) \|\|
	(transform != mCurrentTransform) \|\|
	(scalingMode != mCurrentScalingMode))
	{
	mCurrentCrop = crop;
	mCurrentTransform = transform;
	mCurrentScalingMode = scalingMode;
	mFlinger->invalidateHwcGeometry();
	}

	GLfloat textureMatrix[16];
	mSurfaceTexture->getTransformMatrix(textureMatrix);
	if (memcmp(textureMatrix, mTextureMatrix, sizeof(textureMatrix))) {
	memcpy(mTextureMatrix, textureMatrix, sizeof(textureMatrix));
	mFlinger->invalidateHwcGeometry();
	}

	uint32_t bufWidth = mActiveBuffer->getWidth();
	uint32_t bufHeight = mActiveBuffer->getHeight();
	if (oldActiveBuffer != NULL) {
	if (bufWidth != uint32_t(oldActiveBuffer->width) \|\|
	bufHeight != uint32_t(oldActiveBuffer->height)) {
	mFlinger->invalidateHwcGeometry();
	}
	}

	mCurrentOpacity = getOpacityForFormat(mActiveBuffer->format);
	if (oldOpacity != isOpaque()) {
	recomputeVisibleRegions = true;
	}

	glTexParameterx(GL_TEXTURE_EXTERNAL_OES, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameterx(GL_TEXTURE_EXTERNAL_OES, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

	// update the layer size and release freeze-lock
	const Layer::State& front(drawingState());

	// FIXME: mPostedDirtyRegion = dirty & bounds
	mPostedDirtyRegion.set(front.w, front.h);

	if ((front.w != front.requested_w) \|\|
	(front.h != front.requested_h))
	{
	// check that we received a buffer of the right size
	// (Take the buffer's orientation into account)
	if (mCurrentTransform & Transform::ROT_90) {
	swap(bufWidth, bufHeight);
	}

	if (isFixedSize() \|\|
	(bufWidth == front.requested_w &&
	bufHeight == front.requested_h))
	{
	// Here we pretend the transaction happened by updating the
	// current and drawing states. Drawing state is only accessed
	// in this thread, no need to have it locked
	Layer::State& editDraw(mDrawingState);
	editDraw.w = editDraw.requested_w;
	editDraw.h = editDraw.requested_h;

	// We also need to update the current state so that we don't
	// end-up doing too much work during the next transaction.
	// NOTE: We actually don't need hold the transaction lock here
	// because State::w and State::h are only accessed from
	// this thread
	Layer::State& editTemp(currentState());
	editTemp.w = editDraw.w;
	editTemp.h = editDraw.h;

	// recompute visible region
	recomputeVisibleRegions = true;

	// we now have the correct size, unfreeze the screen
	mFreezeLock.clear();
	}

	LOGD_IF(DEBUG_RESIZE,
	"lockPageFlip : "
	" (layer=%p), buffer (%ux%u, tr=%02x), "
	"requested (%dx%d)",
	this,
	bufWidth, bufHeight, mCurrentTransform,
	front.requested_w, front.requested_h);
	}
	}
	}

	void Layer::unlockPageFlip(
	const Transform& planeTransform, Region& outDirtyRegion)
	{
	Region dirtyRegion(mPostedDirtyRegion);
	if (!dirtyRegion.isEmpty()) {
	mPostedDirtyRegion.clear();
	// The dirty region is given in the layer's coordinate space
	// transform the dirty region by the surface's transformation
	// and the global transformation.
	const Layer::State& s(drawingState());
	const Transform tr(planeTransform * s.transform);
	dirtyRegion = tr.transform(dirtyRegion);

	// At this point, the dirty region is in screen space.
	// Make sure it's constrained by the visible region (which
	// is in screen space as well).
	dirtyRegion.andSelf(visibleRegionScreen);
	outDirtyRegion.orSelf(dirtyRegion);
	}
	if (visibleRegionScreen.isEmpty()) {
	// an invisible layer should not hold a freeze-lock
	// (because it may never be updated and therefore never release it)
	mFreezeLock.clear();
	}
	}

	void Layer::dump(String8& result, char* buffer, size_t SIZE) const
	{
	LayerBaseClient::dump(result, buffer, SIZE);

	sp<const GraphicBuffer> buf0(mActiveBuffer);
	uint32_t w0=0, h0=0, s0=0, f0=0;
	if (buf0 != 0) {
	w0 = buf0->getWidth();
	h0 = buf0->getHeight();
	s0 = buf0->getStride();
	f0 = buf0->format;
	}
	snprintf(buffer, SIZE,
	" "
	"format=%2d, activeBuffer=[%4ux%4u:%4u,%3X],"
	" freezeLock=%p, transform-hint=0x%02x, queued-frames=%d\n",
	mFormat, w0, h0, s0,f0,
	getFreezeLock().get(), getTransformHint(), mQueuedFrames);

	result.append(buffer);

	if (mSurfaceTexture != 0) {
	mSurfaceTexture->dump(result, " ", buffer, SIZE);
	}
	}

	uint32_t Layer::getEffectiveUsage(uint32_t usage) const
	{
	// TODO: should we do something special if mSecure is set?
	if (mProtectedByApp) {
	// need a hardware-protected path to external video sink
	usage \|= GraphicBuffer::USAGE_PROTECTED;
	}
	usage \|= GraphicBuffer::USAGE_HW_COMPOSER;
	return usage;
	}

	uint32_t Layer::getTransformHint() const {
	uint32_t orientation = 0;
	if (!mFlinger->mDebugDisableTransformHint) {
	orientation = getPlaneOrientation();
	if (orientation & Transform::ROT_INVALID) {
	orientation = 0;
	}
	}
	return orientation;
	}

	// ---------------------------------------------------------------------------


	}; // namespace android