camera3: focalLength tag frameworks/base changes.
Change-Id: I59614223ae65e602f3461029cb4b8848fb22950e
diff --git a/core/java/android/hardware/camera2/CaptureResult.java b/core/java/android/hardware/camera2/CaptureResult.java
index aa12d5e..9990142 100644
--- a/core/java/android/hardware/camera2/CaptureResult.java
+++ b/core/java/android/hardware/camera2/CaptureResult.java
@@ -1097,8 +1097,20 @@
new Key<Float>("android.lens.filterDensity", float.class);
/**
- * <p>Lens optical zoom setting</p>
- * <p>Will not be supported on most devices.</p>
+ * <p>The current lens focal length; used for optical zoom.</p>
+ * <p>This setting controls the physical focal length of the camera
+ * device's lens. Changing the focal length changes the field of
+ * view of the camera device, and is usually used for optical zoom.</p>
+ * <p>Like {@link CaptureRequest#LENS_FOCUS_DISTANCE android.lens.focusDistance} and {@link CaptureRequest#LENS_APERTURE android.lens.aperture}, this
+ * setting won't be applied instantaneously, and it may take several
+ * frames before the lens can move to the requested focal length.
+ * While the focal length is still changing, {@link CaptureResult#LENS_STATE android.lens.state} will
+ * be set to MOVING.</p>
+ * <p>This is expected not to be supported on most devices.</p>
+ *
+ * @see CaptureRequest#LENS_APERTURE
+ * @see CaptureRequest#LENS_FOCUS_DISTANCE
+ * @see CaptureResult#LENS_STATE
*/
public static final Key<Float> LENS_FOCAL_LENGTH =
new Key<Float>("android.lens.focalLength", float.class);