replicant-frameworks_native/include/gui/SurfaceTexture.h

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/*
* Copyright (C) 2010 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_GUI_SURFACETEXTURE_H
#define ANDROID_GUI_SURFACETEXTURE_H
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <GLES2/gl2.h>
#include <gui/ISurfaceTexture.h>
#include <ui/GraphicBuffer.h>
#include <utils/threads.h>
#include <utils/Vector.h>
#define ANDROID_GRAPHICS_SURFACETEXTURE_JNI_ID "mSurfaceTexture"
namespace android {
// ----------------------------------------------------------------------------
class IGraphicBufferAlloc;
class SurfaceTexture : public BnSurfaceTexture {
public:
enum { MIN_BUFFER_SLOTS = 3 };
enum { NUM_BUFFER_SLOTS = 32 };
// tex indicates the name OpenGL texture to which images are to be streamed.
// This texture name cannot be changed once the SurfaceTexture is created.
SurfaceTexture(GLuint tex);
virtual ~SurfaceTexture();
// setBufferCount updates the number of available buffer slots. After
// calling this all buffer slots are both unallocated and owned by the
// SurfaceTexture object (i.e. they are not owned by the client).
virtual status_t setBufferCount(int bufferCount);
virtual sp<GraphicBuffer> requestBuffer(int buf, uint32_t w, uint32_t h,
uint32_t format, uint32_t usage);
// dequeueBuffer gets the next buffer slot index for the client to use. If a
// buffer slot is available then that slot index is written to the location
// pointed to by the buf argument and a status of OK is returned. If no
// slot is available then a status of -EBUSY is returned and buf is
// unmodified.
virtual status_t dequeueBuffer(int *buf);
virtual status_t queueBuffer(int buf);
virtual void cancelBuffer(int buf);
virtual status_t setCrop(const Rect& reg);
virtual status_t setTransform(uint32_t transform);
// updateTexImage sets the image contents of the target texture to that of
// the most recently queued buffer.
//
// This call may only be made while the OpenGL ES context to which the
// target texture belongs is bound to the calling thread.
status_t updateTexImage();
// getTransformMatrix retrieves the 4x4 texture coordinate transform matrix
// associated with the texture image set by the most recent call to
// updateTexImage.
//
// This transform matrix maps 2D homogeneous texture coordinates of the form
// (s, t, 0, 1) with s and t in the inclusive range [0, 1] to the texture
// coordinate that should be used to sample that location from the texture.
// Sampling the texture outside of the range of this transform is undefined.
//
// This transform is necessary to compensate for transforms that the stream
// content producer may implicitly apply to the content. By forcing users of
// a SurfaceTexture to apply this transform we avoid performing an extra
// copy of the data that would be needed to hide the transform from the
// user.
//
// The matrix is stored in column-major order so that it may be passed
// directly to OpenGL ES via the glLoadMatrixf or glUniformMatrix4fv
// functions.
void getTransformMatrix(float mtx[16]);
private:
// freeAllBuffers frees the resources (both GraphicBuffer and EGLImage) for
// all slots.
void freeAllBuffers();
// createImage creates a new EGLImage from a GraphicBuffer.
EGLImageKHR createImage(EGLDisplay dpy,
const sp<GraphicBuffer>& graphicBuffer);
enum { INVALID_BUFFER_SLOT = -1 };
struct BufferSlot {
// mGraphicBuffer points to the buffer allocated for this slot or is NULL
// if no buffer has been allocated.
sp<GraphicBuffer> mGraphicBuffer;
// mEglImage is the EGLImage created from mGraphicBuffer.
EGLImageKHR mEglImage;
// mEglDisplay is the EGLDisplay used to create mEglImage.
EGLDisplay mEglDisplay;
// mOwnedByClient indicates whether the slot is currently accessible to a
// client and should not be used by the SurfaceTexture object. It gets
// set to true when dequeueBuffer returns the slot and is reset to false
// when the client calls either queueBuffer or cancelBuffer on the slot.
bool mOwnedByClient;
};
// mSlots is the array of buffer slots that must be mirrored on the client
// side. This allows buffer ownership to be transferred between the client
// and server without sending a GraphicBuffer over binder. The entire array
// is initialized to NULL at construction time, and buffers are allocated
// for a slot when requestBuffer is called with that slot's index.
BufferSlot mSlots[NUM_BUFFER_SLOTS];
// mBufferCount is the number of buffer slots that the client and server
// must maintain. It defaults to MIN_BUFFER_SLOTS and can be changed by
// calling setBufferCount.
int mBufferCount;
// mCurrentTexture is the buffer slot index of the buffer that is currently
// bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
// indicating that no buffer slot is currently bound to the texture. Note,
// however, that a value of INVALID_BUFFER_SLOT does not necessarily mean
// that no buffer is bound to the texture. A call to setBufferCount will
// reset mCurrentTexture to INVALID_BUFFER_SLOT.
int mCurrentTexture;
// mCurrentTextureBuf is the graphic buffer of the current texture. It's
// possible that this buffer is not associated with any buffer slot, so we
// must track it separately in order to properly use
// IGraphicBufferAlloc::freeAllGraphicBuffersExcept.
sp<GraphicBuffer> mCurrentTextureBuf;
// mCurrentCrop is the crop rectangle that applies to the current texture.
// It gets set to mLastQueuedCrop each time updateTexImage is called.
Rect mCurrentCrop;
// mCurrentTransform is the transform identifier for the current texture. It
// gets set to mLastQueuedTransform each time updateTexImage is called.
uint32_t mCurrentTransform;
// mLastQueued is the buffer slot index of the most recently enqueued buffer.
// At construction time it is initialized to INVALID_BUFFER_SLOT, and is
// updated each time queueBuffer is called.
int mLastQueued;
// mLastQueuedCrop is the crop rectangle for the buffer that was most
// recently queued. This gets set to mNextCrop each time queueBuffer gets
// called.
Rect mLastQueuedCrop;
// mLastQueuedTransform is the transform identifier for the buffer that was
// most recently queued. This gets set to mNextTransform each time
// queueBuffer gets called.
uint32_t mLastQueuedTransform;
// mNextCrop is the crop rectangle that will be used for the next buffer
// that gets queued. It is set by calling setCrop.
Rect mNextCrop;
// mNextTransform is the transform identifier that will be used for the next
// buffer that gets queued. It is set by calling setTransform.
uint32_t mNextTransform;
// mTexName is the name of the OpenGL texture to which streamed images will
// be bound when updateTexImage is called. It is set at construction time
// changed with a call to setTexName.
const GLuint mTexName;
// mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to
// allocate new GraphicBuffer objects.
sp<IGraphicBufferAlloc> mGraphicBufferAlloc;
// mAllocdBuffers is mirror of the list of buffers that SurfaceFlinger is
// referencing. This is kept so that gralloc implementations do not need to
// properly handle the case where SurfaceFlinger no longer holds a reference
// to a buffer, but other processes do.
Vector<sp<GraphicBuffer> > mAllocdBuffers;
// mMutex is the mutex used to prevent concurrent access to the member
// variables of SurfaceTexture objects. It must be locked whenever the
// member variables are accessed.
Mutex mMutex;
};
// ----------------------------------------------------------------------------
}; // namespace android
#endif // ANDROID_GUI_SURFACETEXTURE_H