Initial commit of the blimp/ folder and target

blimp/client/android/blimp_view.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BLIMP_CLIENT_ANDROID_BLIMP_VIEW_H_
+#define BLIMP_CLIENT_ANDROID_BLIMP_VIEW_H_
+
+#include "base/android/jni_android.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace gfx {
+class Size;
+}
+
+namespace blimp {
+
+class BlimpCompositorAndroid;
+
+// The native component of org.chromium.blimp.BlimpView.  This builds and
+// maintains a BlimpCompositorAndroid and handles notifying the compositor of
+// SurfaceView surface changes (size, creation, destruction, etc.).
+class BlimpView {
+ public:
+  static bool RegisterJni(JNIEnv* env);
+
+  // |physical_size| is the real display area that can contain content including
+  // system decorations (See android.view.Display#getRealSize()).

[Wez, 2015/09/03 00:49:27]

nit: You mean that this is the total display area, including the area occupied
by system controls, whereas getSize() is the display area not occupied by system
controls?

[David Trainor- moved to gerrit, 2015/09/03 06:33:21]

I think Android calls it system decoration, but I like the rest of your wording
much better. 

+  // |display_size| is the display area that may contain an application window
+  // excluding system decorations (see android.view.Display#getSize()).
+  // |dp_to_pixel| is the scale factor that is required to move from dp
+  // (device independent pixels) to pixels.

[Wez, 2015/09/03 00:49:27]

nit: Aren't Device Independent Pixels called DIPs?

[David Trainor- moved to gerrit, 2015/09/03 06:33:21]

Yeah but Android changed the unit of measurement from dip to dp a few SDK
revisions ago IIRC.  They both still work, but most of the more recent Android
code you'll see will have "10dp."  Not sure why they moved over... I think it's
to mimic "sp" for font sizes.

[Wez, 2015/09/03 18:26:10]

According to
http://developer.android.com/guide/topics/resources/more-resources.html#Dimen...
"dp" is short-hand for "Density-independent Pixel" and "px" is short-hand for
"actual pixel" (i.e. "device" or "physical" pixels).

So I'd recommend renaming dp_to_pixel to dp_to_px, and updating the decription
to use that page's terminology. You'll also want to make explicit which units
the physical & display sizes are in.

Finally, you could include the reference to the Dimensions doc here, if you
think it'd be a useful reference to avoid having to describe all this to n00bs
like me. ;)

+  BlimpView(JNIEnv* env,
+            jobject jobj,
+            const gfx::Size& physical_size,
+            const gfx::Size& display_size,
+            float dp_to_pixel);
+
+  // Methods called from Java via JNI

[Wez, 2015/09/03 00:49:27]

nit: Missing .

[David Trainor- moved to gerrit, 2015/09/03 06:33:21]

Done.

+  void Destroy(JNIEnv* env, jobject jobj);
+  void SetNeedsComposite(JNIEnv* env, jobject jobj);
+  void OnSurfaceChanged(JNIEnv* env,
+                        jobject jobj,
+                        jint format,
+                        jint width,
+                        jint height,
+                        jobject jsurface);
+  void OnSurfaceCreated(JNIEnv* env, jobject jobj);
+  void OnSurfaceDestroyed(JNIEnv* env, jobject jobj);
+  void SetVisibility(JNIEnv* env, jobject jobj, jboolean visible);
+
+ private:
+  virtual ~BlimpView();
+
+  // A reference to the Java object which owns this class.

[Wez, 2015/09/03 00:49:27]

nit: No need for "A" here.

So this reference has no effect on GC...? i.e. we're not creating a
reference-loop here?

[David Trainor- moved to gerrit, 2015/09/03 06:33:21]

We are.  That's on purpose though.

[Wez, 2015/09/03 18:26:10]

OK - sounds like the ownership graph needs clarifying, then?

+  base::android::ScopedJavaGlobalRef<jobject> java_obj_;
+
+  scoped_ptr<BlimpCompositorAndroid> compositor_;
+
+  // The format of the current surface owned by |compositor_|.  See
+  // android.graphics.PixelFormat.java.
+  int current_surface_format_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlimpView);
+};
+
+}  // namespace blimp
+
+#endif  // BLIMP_CLIENT_ANDROID_BLIMP_VIEW_H_