[Chromoting] Initial plumbing for cursor shape.

remoting/proto/video.proto

 // Copyright (c) 2012 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.
 
 // Protocol for video messages.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
@@ skipping 17 matching lines @@
   optional int32 height = 4;
 
   // The encoding used for this image update.
   optional Encoding encoding = 5 [default = ENCODING_INVALID];
   
   // Width and height of the whole screen.
   optional int32 screen_width = 6;
   optional int32 screen_height = 7;
 }
 
+message CursorShapeInfo {

[Sergey Ulanov, 2012/05/15 23:51:34]

Why is this in video.proto? wouldn't it be better to send cursor shape over the
control channel?

[Wez, 2012/05/16 00:20:04]

We discussed this and agreed the video channel was appropriate since this is
part of what the user sees displayed.

[Sergey Ulanov, 2012/05/16 20:39:12]

As we discussed yesterday: It may be better to use events or control channel for
these events - it is more future proof approach. With WebRTC we will use RTP for
the video channel, so it will not be possible to send these messages as part of
the video stream.  

[garykac, 2012/05/22 00:42:03]

Done.

+  // Width, height (in screen pixels) of the cursor (and mask).
+  optional int32 width = 1;
+  optional int32 height = 2;
+
+  // X,Y coordinates (in screen pixels) of the cursor hotspot.
+  optional int32 hotspot_x = 3;
+  optional int32 hotspot_y = 4;
+
+  // Cursor pixmap data is stored in VideoPacket |data| field.
+}
+
 // TODO(hclam): Remove this message once we can obtain dirty rects from libvpx.
 message Rect {
   optional int32 x = 1;
   optional int32 y = 2;
   optional int32 width = 3;
   optional int32 height = 4;
 }
 
 message VideoPacket {
   // Bitmasks for use in the flags field below.
   //
   // The encoder may fragment one update into multiple partitions.
   // Each partition may be divided into multiple packets depending on
   // how the encoder outputs data. Thus, one update can logically
   // consist of multiple packets. The FIRST_PACKET and LAST_PACKET
   // flags are used to indicate the start and end of a partition. The
   // LAST_PARTITION flag is set for the last packet in the last
   // partition. Here are notable consequences:
   //  * Both FIRST_PACKET and LAST_PACKET may be set if an update is only
   //    one packet long.
   //  * The VideoPacketFormat is only supplied in a FIRST_PACKET.
   //  * LAST_PARTITION can be set only in packet that has LAST_PACKET set.
   //  * An local update cannot change format between a FIRST_PACKET and
   //    a LAST_PACKET.
   //  * All packets in one logical update must be processed in order, and
   //    packets may not be skipped.
+  // CURSOR_SHAPE specifies a standalone cursor shape packet. These packets
+  // are not combined with any other video packet.
   enum Flags {
     FIRST_PACKET = 1;
     LAST_PACKET = 2;
     LAST_PARTITION = 4;
+    CURSOR_SHAPE = 8;

[Sergey Ulanov, 2012/05/15 23:51:34]

Do we really need a flag for this? We can just use presence of cursor_shape to
determine the presence of cursor_shape info.

[garykac, 2012/05/22 00:42:03]

Done.

   }
   optional int32 flags = 1 [default = 0];
 
   // The sequence number of the partial data for updating a rectangle.
   optional int32 sequence_number = 2 [default = 0];
 
   optional int32 timestamp = 3 [default = 0];
 
   // This is provided on the first packet of the rectangle data, when
   // the flags has FIRST_PACKET set.
   optional VideoPacketFormat format = 4;
 
   optional bytes data = 5;
 
   // This field is only for VP8 to provide out-of-band information of dirty
   // rects.
   // TODO(hclam): Remove this field when we can obtain this information from
   // libvpx.
   repeated Rect dirty_rects = 6;
 
   // Time in milliseconds spent in capturing this video frame.
   optional int32 capture_time_ms = 7;
 
   // Time in milliseconds spent in encoding this video frame.
   optional int32 encode_time_ms = 8;
 
   // The most recent sequence number received from the client on the event
   // channel.
   optional int64 client_sequence_number = 9;
+
+  // Description of the current cursor shape.
+  optional CursorShapeInfo cursor_shape = 10;
 }