Add C++ SurfaceTextureHandler

talk/app/webrtc/java/jni/surfacetexturehelper_jni.h

+/*
+ * libjingle
+ * Copyright 2015 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef TALK_APP_WEBRTC_JAVA_JNI_SURFACETEXTUREHELPER_JNI_H_
+#define TALK_APP_WEBRTC_JAVA_JNI_SURFACETEXTUREHELPER_JNI_H_
+
+#include <jni.h>
+
+#include "talk/app/webrtc/java/jni/jni_helpers.h"
+#include "talk/app/webrtc/java/jni/native_handle_impl.h"
+#include "webrtc/base/refcount.h"
+#include "webrtc/base/scoped_ref_ptr.h"
+#include "webrtc/common_video/interface/video_frame_buffer.h"
+
+namespace webrtc_jni {
+
+// Helper class to create and synchronize access to an Android SurfaceTexture.
+// It is used for creating webrtc::VideoFrameBuffers from a SurfaceTexture when
+// the SurfaceTexture has been updated.
+// When the VideoFrameBuffer is released, this class returns the buffer to the
+// java SurfaceTextureHelper so it can be updated safely. The VideoFrameBuffer
+// can be released on an arbitrary thread.
+// SurfaceTextureHelper is reference counted to make sure that it is not
+// destroyed while a VideoFrameBuffer is in use.
+// This class is the C++ counterpart of the java class SurfaceTextureHelper.
+// Usage:
+// 1. Create an instance of this class.
+// 2. Call GetJavaSurfaceTextureHelper to get the Java SurfaceTextureHelper.
+// 3. Register a listener to the Java SurfaceListener and start producing
+// new buffers.
+// 3. Call CreateTextureFrame to wrap the Java texture in a VideoFrameBuffer.
+class SurfaceTextureHelper : public rtc::RefCountInterface {
+ public:
+  static rtc::scoped_refptr<SurfaceTextureHelper> Create(
+      jobject shared_egl_context);
+
+  // Returns the Java SurfaceTextureHelper.
+  jobject GetJavaSurfaceTextureHelper() const {
+    return *j_surface_texture_helper_;
+  }
+
+  rtc::scoped_refptr<webrtc::VideoFrameBuffer> CreateTextureFrame(
+      int width,
+      int height,
+      const NativeHandleImpl& native_handle);
+
+ protected:
+  explicit SurfaceTextureHelper(jobject shared_egl_context);
+  ~SurfaceTextureHelper();
+
+ private:
+  class TextureBuffer;
+  //  May be called on arbitrary thread.
+  void ReturnTextureFrame();

[magjed_webrtc, 2015/09/27 11:26:41]

Can this be made: 'void ReturnTextureFrame() const'?

[perkj_webrtc, 2015/09/28 07:22:47]

Done.

+
+  const ScopedGlobalRef<jclass> j_surface_texture_helper_class_;

[magjed_webrtc, 2015/09/27 11:26:41]

FYI - You don't need to hold the class yourself if you are using FindClass() in
classreferenceholder.h. Actually, I think it is better to hold the class
ourselves so that org.webrtc.SurfaceTextureHelper is only loaded if it's used.

[perkj_webrtc, 2015/09/28 07:22:47]

Acknowledged.

+  const ScopedGlobalRef<jobject> j_surface_texture_helper_;
+  const jmethodID j_return_texture_method_;
+};
+
+}  // namespace webrtc_jni
+
+#endif  // TALK_APP_WEBRTC_JAVA_JNI_SURFACETEXTUREHELPER_JNI_H_