Refactoring of the client-side input pipeline and scaling dimension management.

remoting/base/util.cc

 // Copyright (c) 2011 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.
 
 #include "base/logging.h"
 #include "base/stringprintf.h"
 #include "base/time.h"
 #include "media/base/video_frame.h"
 #include "media/base/yuv_convert.h"
 #include "remoting/base/util.h"
@@ skipping 130 matching lines @@
 
 SkIRect AlignRect(const SkIRect& rect) {
   int x = RoundToTwosMultiple(rect.fLeft);
   int y = RoundToTwosMultiple(rect.fTop);
   int right = RoundToTwosMultiple(rect.fRight + 1);
   int bottom = RoundToTwosMultiple(rect.fBottom + 1);
   return SkIRect::MakeXYWH(x, y, right - x, bottom - y);
 }
 
 SkIRect ScaleRect(const SkIRect& rect,
-                  double horizontal_ratio,
-                  double vertical_ratio) {
-  int x = rect.fLeft * horizontal_ratio;
-  int y = rect.fTop * vertical_ratio;
-  int w = rect.fRight * horizontal_ratio - x;
-  int h = rect.fBottom * vertical_ratio - y;
-
-  return SkIRect::MakeXYWH(x, y, w, h);
+                  const SkISize& in_size,
+                  const SkISize& out_size) {
+  int x1 = (rect.fLeft * out_size.width()) / in_size.width();

[Sergey Ulanov, 2011/12/20 00:05:35]

here and below, left() instead of fLeft? 

[Wez, 2011/12/20 07:14:14]

Done.

+  int y1 = (rect.fTop * out_size.height()) / in_size.height();
+  int x2 = (rect.fRight * out_size.width() + out_size.width()-1) /

[Sergey Ulanov, 2011/12/20 00:05:35]

nit: spaces around minus here and in the next line

[Wez, 2011/12/20 07:14:14]

Done.

+      in_size.width();
+  int y2 = (rect.fBottom * out_size.height() + out_size.height()-1) /

[Sergey Ulanov, 2011/12/20 00:05:35]

maybe call it right and bottom instead of x2 and y2 - for consistency with other
functions

[Sergey Ulanov, 2011/12/20 00:05:35]

I think it would be useful to add a comment saying that we want scaled rect to
cover the non-scaled rect, to explain why we need  "+out_size.height()-1" here.

[Wez, 2011/12/20 07:14:14]

Done.

[Wez, 2011/12/20 07:14:14]

I've updated the comment on ScaleRect() in the header to explain that subtlety.

+      in_size.height();
+  return SkIRect::MakeXYWH(x1, y1, x2-x1, y2-y1);

[Sergey Ulanov, 2011/12/20 00:05:35]

Use MakeLTRB() here?

[Wez, 2011/12/20 07:14:14]

Done.

 }
 
 void CopyRect(const uint8* src_plane,
               int src_plane_stride,
               uint8* dest_plane,
               int dest_plane_stride,
               int bytes_per_pixel,
               const SkIRect& rect) {
- // Get the address of the starting point.
+  // Get the address of the starting point.
   const int src_y_offset = src_plane_stride * rect.fTop;
   const int dest_y_offset = dest_plane_stride * rect.fTop;
   const int x_offset = bytes_per_pixel * rect.fLeft;
   src_plane += src_y_offset + x_offset;
   dest_plane += dest_y_offset + x_offset;
 
   // Copy pixels in the rectangle line by line.
   const int bytes_per_line = bytes_per_pixel * rect.width();
   const int height = rect.height();
   for (int i = 0 ; i < height; ++i) {
     memcpy(dest_plane, src_plane, bytes_per_line);
     src_plane += src_plane_stride;
     dest_plane += dest_plane_stride;
   }
 }
 
 }  // namespace remoting