GLConsumer: Allow creation in detached mode

Adds a constructor that doesn't require a GLES texture name and sets
up the GLConsumer in detached mode.

Bug: 15616428
Change-Id: Idc9ea2e59baa24bbd959da9fffe0fb71c0aa9818

2 files changed, 49 insertions, 17 deletions

diff --git a/include/gui/GLConsumer.h b/include/gui/GLConsumer.h
index 787b3d4..1aacee9 100644
--- a/include/gui/GLConsumer.h
+++ b/include/gui/GLConsumer.h
@@ -56,23 +56,13 @@ public:
     enum { TEXTURE_EXTERNAL = 0x8D65 }; // GL_TEXTURE_EXTERNAL_OES
     typedef ConsumerBase::FrameAvailableListener FrameAvailableListener;
 
-    // GLConsumer constructs a new GLConsumer object. tex indicates the
-    // name of the OpenGL ES texture to which images are to be streamed.
-    // allowSynchronousMode specifies whether or not synchronous mode can be
-    // enabled. texTarget specifies the OpenGL ES texture target to which the
-    // texture will be bound in updateTexImage. useFenceSync specifies whether
-    // fences should be used to synchronize access to buffers if that behavior
-    // is enabled at compile-time. A custom bufferQueue can be specified
-    // if behavior for queue/dequeue/connect etc needs to be customized.
-    // Otherwise a default BufferQueue will be created and used.
-    //
-    // For legacy reasons, the GLConsumer is created in a state where it is
-    // considered attached to an OpenGL ES context for the purposes of the
-    // attachToContext and detachFromContext methods. However, despite being
-    // considered "attached" to a context, the specific OpenGL ES context
-    // doesn't get latched until the first call to updateTexImage. After that
-    // point, all calls to updateTexImage must be made with the same OpenGL ES
-    // context current.
+    // GLConsumer constructs a new GLConsumer object. If the constructor with
+    // the tex parameter is used, tex indicates the name of the OpenGL ES
+    // texture to which images are to be streamed. texTarget specifies the
+    // OpenGL ES texture target to which the texture will be bound in
+    // updateTexImage. useFenceSync specifies whether fences should be used to
+    // synchronize access to buffers if that behavior is enabled at
+    // compile-time.
     //
     // A GLConsumer may be detached from one OpenGL ES context and then
     // attached to a different context using the detachFromContext and
@@ -80,10 +70,25 @@ public:
     // purely to allow a GLConsumer to be transferred from one consumer
     // context to another. If such a transfer is not needed there is no
     // requirement that either of these methods be called.
+    //
+    // If the constructor with the tex parameter is used, the GLConsumer is
+    // created in a state where it is considered attached to an OpenGL ES
+    // context for the purposes of the attachToContext and detachFromContext
+    // methods. However, despite being considered "attached" to a context, the
+    // specific OpenGL ES context doesn't get latched until the first call to
+    // updateTexImage. After that point, all calls to updateTexImage must be
+    // made with the same OpenGL ES context current.
+    //
+    // If the constructor without the tex parameter is used, the GLConsumer is
+    // created in a detached state, and attachToContext must be called before
+    // calls to updateTexImage.
     GLConsumer(const sp<IGraphicBufferConsumer>& bq,
             uint32_t tex, uint32_t texureTarget, bool useFenceSync,
             bool isControlledByApp);
 
+    GLConsumer(const sp<IGraphicBufferConsumer>& bq, uint32_t texureTarget,
+            bool useFenceSync, bool isControlledByApp);
+
     // updateTexImage acquires the most recently queued buffer, and sets the
     // image contents of the target texture to it.
     //
diff --git a/libs/gui/GLConsumer.cpp b/libs/gui/GLConsumer.cpp
index 3215b2f..924fc0d 100644
--- a/libs/gui/GLConsumer.cpp
+++ b/libs/gui/GLConsumer.cpp
@@ -143,6 +143,33 @@ GLConsumer::GLConsumer(const sp<IGraphicBufferConsumer>& bq, uint32_t tex,
     mConsumer->setConsumerUsageBits(DEFAULT_USAGE_FLAGS);
 }
 
+GLConsumer::GLConsumer(const sp<IGraphicBufferConsumer>& bq, uint32_t texTarget,
+        bool useFenceSync, bool isControlledByApp) :
+    ConsumerBase(bq, isControlledByApp),
+    mCurrentTransform(0),
+    mCurrentScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
+    mCurrentFence(Fence::NO_FENCE),
+    mCurrentTimestamp(0),
+    mCurrentFrameNumber(0),
+    mDefaultWidth(1),
+    mDefaultHeight(1),
+    mFilteringEnabled(true),
+    mTexName(-1),
+    mUseFenceSync(useFenceSync),
+    mTexTarget(texTarget),
+    mEglDisplay(EGL_NO_DISPLAY),
+    mEglContext(EGL_NO_CONTEXT),
+    mCurrentTexture(BufferQueue::INVALID_BUFFER_SLOT),
+    mAttached(false)
+{
+    ST_LOGV("GLConsumer");
+
+    memcpy(mCurrentTransformMatrix, mtxIdentity,
+            sizeof(mCurrentTransformMatrix));
+
+    mConsumer->setConsumerUsageBits(DEFAULT_USAGE_FLAGS);
+}
+
 status_t GLConsumer::setDefaultMaxBufferCount(int bufferCount) {
     Mutex::Autolock lock(mMutex);
     return mConsumer->setDefaultMaxBufferCount(bufferCount);