am 82c53806: Merge "SurfaceTexture: improve texture matrix computation" into jb-dev (5ce4b59f) · Commits · e / os / android_frameworks_native

include/gui/SurfaceTexture.h

+9 −0

Original line number	Original line	Diff line number	Diff line
	@@ -144,6 +144,10 @@ public:
	// updateTexImage() is called.		// updateTexImage() is called.
	status_t setDefaultBufferSize(uint32_t width, uint32_t height);		status_t setDefaultBufferSize(uint32_t width, uint32_t height);

			// setFilteringEnabled sets whether the transform matrix should be computed
			// for use with bilinear filtering.
			void setFilteringEnabled(bool enabled);

	// getCurrentBuffer returns the buffer associated with the current image.		// getCurrentBuffer returns the buffer associated with the current image.
	sp<GraphicBuffer> getCurrentBuffer() const;		sp<GraphicBuffer> getCurrentBuffer() const;

	@@ -289,6 +293,11 @@ private:

	uint32_t mDefaultWidth, mDefaultHeight;		uint32_t mDefaultWidth, mDefaultHeight;

			// mFilteringEnabled indicates whether the transform matrix is computed for
			// use with bilinear filtering. It defaults to true and is changed by
			// setFilteringEnabled().
			bool mFilteringEnabled;

	// mTexName is the name of the OpenGL texture to which streamed images will		// 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		// be bound when updateTexImage is called. It is set at construction time
	// and can be changed with a call to attachToContext.		// and can be changed with a call to attachToContext.

libs/gui/SurfaceTexture.cpp

+52 −32

Original line number	Original line	Diff line number	Diff line
	@@ -108,6 +108,7 @@ SurfaceTexture::SurfaceTexture(GLuint tex, bool allowSynchronousMode,
	GLenum texTarget, bool useFenceSync, const sp<BufferQueue> &bufferQueue) :		GLenum texTarget, bool useFenceSync, const sp<BufferQueue> &bufferQueue) :
	mCurrentTransform(0),		mCurrentTransform(0),
	mCurrentTimestamp(0),		mCurrentTimestamp(0),
			mFilteringEnabled(true),
	mTexName(tex),		mTexName(tex),
	#ifdef USE_FENCE_SYNC		#ifdef USE_FENCE_SYNC
	mUseFenceSync(useFenceSync),		mUseFenceSync(useFenceSync),
	@@ -503,6 +504,15 @@ void SurfaceTexture::getTransformMatrix(float mtx[16]) {
	memcpy(mtx, mCurrentTransformMatrix, sizeof(mCurrentTransformMatrix));		memcpy(mtx, mCurrentTransformMatrix, sizeof(mCurrentTransformMatrix));
	}		}

			void SurfaceTexture::setFilteringEnabled(bool enabled) {
			Mutex::Autolock lock(mMutex);
			bool needsRecompute = mFilteringEnabled != enabled;
			mFilteringEnabled = enabled;
			if (needsRecompute) {
			computeCurrentTransformMatrix();
			}
			}

	void SurfaceTexture::computeCurrentTransformMatrix() {		void SurfaceTexture::computeCurrentTransformMatrix() {
	ST_LOGV("computeCurrentTransformMatrix");		ST_LOGV("computeCurrentTransformMatrix");

	@@ -534,39 +544,49 @@ void SurfaceTexture::computeCurrentTransformMatrix() {

	sp<GraphicBuffer>& buf(mCurrentTextureBuf);		sp<GraphicBuffer>& buf(mCurrentTextureBuf);
	Rect cropRect = mCurrentCrop;		Rect cropRect = mCurrentCrop;
	float tx, ty, sx, sy;		float tx = 0.0f, ty = 0.0f, sx = 1.0f, sy = 1.0f;
	if (!cropRect.isEmpty()) {
	// In order to prevent bilinear sampling at the of the crop rectangle we
	// may need to shrink it by 2 texels in each direction. Normally this
	// would just need to take 1/2 a texel off each end, but because the
	// chroma channels will likely be subsampled we need to chop off a whole
	// texel. This will cause artifacts if someone does nearest sampling
	// with 1:1 pixel:texel ratio, but it's impossible to simultaneously
	// accomodate the bilinear and nearest sampling uses.
	//
	// If nearest sampling turns out to be a desirable usage of these
	// textures then we could add the ability to switch a SurfaceTexture to
	// nearest-mode. Preferably, however, the image producers (video
	// decoder, camera, etc.) would simply not use a crop rectangle (or at
	// least not tell the framework about it) so that the GPU can do the
	// correct edge behavior.
	const float shrinkAmount = 1.0f; // the amount that each edge is shrunk

	float bufferWidth = buf->getWidth();		float bufferWidth = buf->getWidth();
	float bufferHeight = buf->getHeight();		float bufferHeight = buf->getHeight();
			if (!cropRect.isEmpty()) {
			float shrinkAmount = 0.0f;
			if (mFilteringEnabled) {
			// In order to prevent bilinear sampling beyond the edge of the
			// crop rectangle we may need to shrink it by 2 texels in each
			// dimension. Normally this would just need to take 1/2 a texel
			// off each end, but because the chroma channels of YUV420 images
			// are subsampled we may need to shrink the crop region by a whole
			// texel on each side.
			switch (buf->getPixelFormat()) {
			case PIXEL_FORMAT_RGBA_8888:
			case PIXEL_FORMAT_RGBX_8888:
			case PIXEL_FORMAT_RGB_888:
			case PIXEL_FORMAT_RGB_565:
			case PIXEL_FORMAT_BGRA_8888:
			case PIXEL_FORMAT_RGBA_5551:
			case PIXEL_FORMAT_RGBA_4444:
			// We know there's no subsampling of any channels, so we
			// only need to shrink by a half a pixel.
			shrinkAmount = 0.5;

			default:
			// If we don't recognize the format, we must assume the
			// worst case (that we care about), which is YUV420.
			shrinkAmount = 1.0;
			}
			}

			// Only shrink the dimensions that are not the size of the buffer.
			if (cropRect.width() < bufferWidth) {
	tx = (float(cropRect.left) + shrinkAmount) / bufferWidth;		tx = (float(cropRect.left) + shrinkAmount) / bufferWidth;
	ty = (float(bufferHeight - cropRect.bottom) + shrinkAmount) /
	bufferHeight;
	sx = (float(cropRect.width()) - (2.0f * shrinkAmount)) /		sx = (float(cropRect.width()) - (2.0f * shrinkAmount)) /
	bufferWidth;		bufferWidth;
			}
			if (cropRect.height() < bufferHeight) {
			ty = (float(bufferHeight - cropRect.bottom) + shrinkAmount) /
			bufferHeight;
	sy = (float(cropRect.height()) - (2.0f * shrinkAmount)) /		sy = (float(cropRect.height()) - (2.0f * shrinkAmount)) /
	bufferHeight;		bufferHeight;
	} else {		}
	tx = 0.0f;
	ty = 0.0f;
	sx = 1.0f;
	sy = 1.0f;
	}		}
	float crop[16] = {		float crop[16] = {
	sx, 0, 0, 0,		sx, 0, 0, 0,