/*
* Copyright 2013 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.
*/
#ifndef ANDROID_SF_VIRTUAL_DISPLAY_SURFACE_H
#define ANDROID_SF_VIRTUAL_DISPLAY_SURFACE_H
#include "DisplaySurface.h"
#include "HWComposerBufferCache.h"
#include <gui/ConsumerBase.h>
#include <gui/IGraphicBufferProducer.h>
// ---------------------------------------------------------------------------
namespace android {
// ---------------------------------------------------------------------------
class HWComposer;
class IProducerListener;
/* This DisplaySurface implementation supports virtual displays, where GLES
* and/or HWC compose into a buffer that is then passed to an arbitrary
* consumer (the sink) running in another process.
*
* The simplest case is when the virtual display will never use the h/w
* composer -- either the h/w composer doesn't support writing to buffers, or
* there are more virtual displays than it supports simultaneously. In this
* case, the GLES driver works directly with the output buffer queue, and
* calls to the VirtualDisplay from SurfaceFlinger and DisplayHardware do
* nothing.
*
* If h/w composer might be used, then each frame will fall into one of three
* configurations: GLES-only, HWC-only, and MIXED composition. In all of these,
* we must provide a FB target buffer and output buffer for the HWC set() call.
*
* In GLES-only composition, the GLES driver is given a buffer from the sink to
* render into. When the GLES driver queues the buffer to the
* VirtualDisplaySurface, the VirtualDisplaySurface holds onto it instead of
* immediately queueing it to the sink. The buffer is used as both the FB
* target and output buffer for HWC, though on these frames the HWC doesn't
* do any work for this display and doesn't write to the output buffer. After
* composition is complete, the buffer is queued to the sink.
*
* In HWC-only composition, the VirtualDisplaySurface dequeues a buffer from
* the sink and passes it to HWC as both the FB target buffer and output
* buffer. The HWC doesn't need to read from the FB target buffer, but does
* write to the output buffer. After composition is complete, the buffer is
* queued to the sink.
*
* On MIXED frames, things become more complicated, since some h/w composer
* implementations can't read from and write to the same buffer. This class has
* an internal BufferQueue that it uses as a scratch buffer pool. The GLES
* driver is given a scratch buffer to render into. When it finishes rendering,
* the buffer is queued and then immediately acquired by the
* VirtualDisplaySurface. The scratch buffer is then used as the FB target
* buffer for HWC, and a separate buffer is dequeued from the sink and used as
* the HWC output buffer. When HWC composition is complete, the scratch buffer
* is released and the output buffer is queued to the sink.
*/
class VirtualDisplaySurface : public DisplaySurface,
public BnGraphicBufferProducer,
private ConsumerBase {
public:
VirtualDisplaySurface(HWComposer& hwc, int32_t dispId,
const sp<IGraphicBufferProducer>& sink,
const sp<IGraphicBufferProducer>& bqProducer,
const sp<IGraphicBufferConsumer>& bqConsumer,
const String8& name);
//
// DisplaySurface interface
//
virtual status_t beginFrame(bool mustRecompose);
virtual status_t prepareFrame(CompositionType compositionType);
#ifndef USE_HWC2
virtual status_t compositionComplete();
#endif
virtual status_t advanceFrame();
virtual void onFrameCommitted();
virtual void dumpAsString(String8& result) const;
virtual void resizeBuffers(const uint32_t w, const uint32_t h);
virtual const sp<Fence>& getClientTargetAcquireFence() const override;
private:
enum Source {SOURCE_SINK = 0, SOURCE_SCRATCH = 1};
virtual ~VirtualDisplaySurface();
//
// IGraphicBufferProducer interface, used by the GLES driver.
//
virtual status_t requestBuffer(int pslot, sp<GraphicBuffer>* outBuf);
virtual status_t setMaxDequeuedBufferCount(int maxDequeuedBuffers);
virtual status_t setAsyncMode(bool async);
virtual status_t dequeueBuffer(int* pslot, sp<Fence>* fence, uint32_t w,
uint32_t h, PixelFormat format, uint32_t usage,
FrameEventHistoryDelta *outTimestamps);
virtual status_t detachBuffer(int slot);
virtual status_t detachNextBuffer(sp<GraphicBuffer>* outBuffer,
sp<Fence>* outFence);
virtual status_t attachBuffer(int* slot, const sp<GraphicBuffer>& buffer);
virtual status_t queueBuffer(int pslot,
const QueueBufferInput& input, QueueBufferOutput* output);
virtual status_t cancelBuffer(int pslot, const sp<Fence>& fence);
virtual int query(int what, int* value);
virtual status_t connect(const sp<IProducerListener>& listener,
int api, bool producerControlledByApp, QueueBufferOutput* output);
virtual status_t disconnect(int api, DisconnectMode mode);
virtual status_t setSidebandStream(const sp<NativeHandle>& stream);
virtual void allocateBuffers(uint32_t width, uint32_t height,
PixelFormat format, uint32_t usage);
virtual status_t allowAllocation(bool allow);
virtual status_t setGenerationNumber(uint32_t generationNumber);
virtual String8 getConsumerName() const override;
virtual status_t setSharedBufferMode(bool sharedBufferMode) override;
virtual status_t setAutoRefresh(bool autoRefresh) override;
virtual status_t setDequeueTimeout(nsecs_t timeout) override;
virtual status_t getLastQueuedBuffer(sp<GraphicBuffer>* outBuffer,
sp<Fence>* outFence, float outTransformMatrix[16]) override;
virtual status_t getUniqueId(uint64_t* outId) const override;
//
// Utility methods
//
static Source fbSourceForCompositionType(CompositionType type);
status_t dequeueBuffer(Source source, PixelFormat format, uint32_t usage,
int* sslot, sp<Fence>* fence);
void updateQueueBufferOutput(QueueBufferOutput&& qbo);
void resetPerFrameState();
status_t refreshOutputBuffer();
// Both the sink and scratch buffer pools have their own set of slots
// ("source slots", or "sslot"). We have to merge these into the single
// set of slots used by the GLES producer ("producer slots" or "pslot") and
// internally in the VirtualDisplaySurface. To minimize the number of times
// a producer slot switches which source it comes from, we map source slot
// numbers to producer slot numbers differently for each source.
static int mapSource2ProducerSlot(Source source, int sslot);
static int mapProducer2SourceSlot(Source source, int pslot);
//
// Immutable after construction
//
HWComposer& mHwc;
const int32_t mDisplayId;
const String8 mDisplayName;
sp<IGraphicBufferProducer> mSource[2]; // indexed by SOURCE_*
uint32_t mDefaultOutputFormat;
//
// Inter-frame state
//
// To avoid buffer reallocations, we track the buffer usage and format
// we used on the previous frame and use it again on the new frame. If
// the composition type changes or the GLES driver starts requesting
// different usage/format, we'll get a new buffer.
uint32_t mOutputFormat;
uint32_t mOutputUsage;
// Since we present a single producer interface to the GLES driver, but
// are internally muxing between the sink and scratch producers, we have
// to keep track of which source last returned each producer slot from
// dequeueBuffer. Each bit in mProducerSlotSource corresponds to a producer
// slot. Both mProducerSlotSource and mProducerBuffers are indexed by a
// "producer slot"; see the mapSlot*() functions.
uint64_t mProducerSlotSource;
sp<GraphicBuffer> mProducerBuffers[BufferQueueDefs::NUM_BUFFER_SLOTS];
// The QueueBufferOutput with the latest info from the sink, and with the
// transform hint cleared. Since we defer queueBuffer from the GLES driver
// to the sink, we have to return the previous version.
// Moves instead of copies are performed to avoid duplicate
// FrameEventHistoryDeltas.
QueueBufferOutput mQueueBufferOutput;
// Details of the current sink buffer. These become valid when a buffer is
// dequeued from the sink, and are used when queueing the buffer.
uint32_t mSinkBufferWidth, mSinkBufferHeight;
//
// Intra-frame state
//
// Composition type and GLES buffer source for the current frame.
// Valid after prepareFrame(), cleared in onFrameCommitted.
CompositionType mCompositionType;
// mFbFence is the fence HWC should wait for before reading the framebuffer
// target buffer.
sp<Fence> mFbFence;
// mOutputFence is the fence HWC should wait for before writing to the
// output buffer.
sp<Fence> mOutputFence;
// Producer slot numbers for the buffers to use for HWC framebuffer target
// and output.
int mFbProducerSlot;
int mOutputProducerSlot;
// Debug only -- track the sequence of events in each frame so we can make
// sure they happen in the order we expect. This class implicitly models
// a state machine; this enum/variable makes it explicit.
//
// +-----------+-------------------+-------------+
// | State | Event || Next State |
// +-----------+-------------------+-------------+
// | IDLE | beginFrame || BEGUN |
// | BEGUN | prepareFrame || PREPARED |
// | PREPARED | dequeueBuffer [1] || GLES |
// | PREPARED | advanceFrame [2] || HWC |
// | GLES | queueBuffer || GLES_DONE |
// | GLES_DONE | advanceFrame || HWC |
// | HWC | onFrameCommitted || IDLE |
// +-----------+-------------------++------------+
// [1] COMPOSITION_GLES and COMPOSITION_MIXED frames.
// [2] COMPOSITION_HWC frames.
//
enum DbgState {
// no buffer dequeued, don't know anything about the next frame
DBG_STATE_IDLE,
// output buffer dequeued, framebuffer source not yet known
DBG_STATE_BEGUN,
// output buffer dequeued, framebuffer source known but not provided
// to GLES yet.
DBG_STATE_PREPARED,
// GLES driver has a buffer dequeued
DBG_STATE_GLES,
// GLES driver has queued the buffer, we haven't sent it to HWC yet
DBG_STATE_GLES_DONE,
// HWC has the buffer for this frame
DBG_STATE_HWC,
};
DbgState mDbgState;
CompositionType mDbgLastCompositionType;
const char* dbgStateStr() const;
static const char* dbgSourceStr(Source s);
bool mMustRecompose;
#ifdef USE_HWC2
HWComposerBufferCache mHwcBufferCache;
#endif
bool mForceHwcCopy;
};
// ---------------------------------------------------------------------------
} // namespace android
// ---------------------------------------------------------------------------
#endif // ANDROID_SF_VIRTUAL_DISPLAY_SURFACE_H