content/common/android/surface_texture_bridge.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_COMMON_ANDROID_SURFACE_TEXTURE_BRIDGE_H_
   6 #define CONTENT_COMMON_ANDROID_SURFACE_TEXTURE_BRIDGE_H_
   7
   8 #include <jni.h>
   9
  10 #include "base/android/scoped_java_ref.h"
  11 #include "base/callback.h"
  12 #include "base/memory/ref_counted.h"
  13
  14 struct ANativeWindow;
  15
  16 namespace content {
  17
  18 // This class serves as a bridge for native code to call java functions inside
  19 // android SurfaceTexture class.
  20 class SurfaceTextureBridge
  21     : public base::RefCountedThreadSafe<SurfaceTextureBridge>{
  22  public:
  23   explicit SurfaceTextureBridge(int texture_id);
  24
  25   // Set the listener callback, which will be invoked on the same thread that
  26   // is being called from here for registration.
  27   // Note: Since callbacks come in from Java objects that might outlive objects
  28   // being referenced from the callback, the only robust way here is to create
  29   // the callback from a weak pointer to your object.
  30   void SetFrameAvailableCallback(const base::Closure& callback);
  31
  32   // Update the texture image to the most recent frame from the image stream.
  33   void UpdateTexImage();
  34
  35   // Retrieve the 4x4 texture coordinate transform matrix associated with the
  36   // texture image set by the most recent call to updateTexImage.
  37   void GetTransformMatrix(float mtx[16]);
  38
  39   // Set the default size of the image buffers.
  40   void SetDefaultBufferSize(int width, int height);
  41
  42   // Attach the SurfaceTexture to the given texture in the GL context that is
  43   // current on the calling thread.
  44   void AttachToGLContext(int texture_id);
  45
  46   // Detaches the SurfaceTexture from the context that owns its current GL
  47   // texture. Must be called with that context current on the calling thread.
  48   void DetachFromGLContext();
  49
  50   // Creates a native render surface for this surface texture.
  51   // The caller must release the underlying reference when done with the handle
  52   // by calling ANativeWindow_release().
  53   ANativeWindow* CreateSurface();
  54
  55   int texture_id() const {
  56     return texture_id_;
  57   }
  58
  59   const base::android::JavaRef<jobject>& j_surface_texture() const {
  60     return j_surface_texture_;
  61   }
  62
  63  private:
  64   friend class base::RefCountedThreadSafe<SurfaceTextureBridge>;
  65   ~SurfaceTextureBridge();
  66
  67   const int texture_id_;
  68
  69   // Java SurfaceTexture instance.
  70   base::android::ScopedJavaGlobalRef<jobject> j_surface_texture_;
  71
  72   DISALLOW_COPY_AND_ASSIGN(SurfaceTextureBridge);
  73 };
  74
  75 }  // namespace content
  76
  77 #endif  // CONTENT_COMMON_ANDROID_SURFACE_TEXTURE_BRIDGE_H_