[Thumbnails] Specify copy size in Pixels, not DIPs

chrome/browser/thumbnails/simple_thumbnail_crop_unittest.cc

 // 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.
 
 #include "chrome/browser/thumbnails/simple_thumbnail_crop.h"
 
 #include "base/basictypes.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/thumbnails/thumbnailing_context.h"
 #include "chrome/common/render_messages.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
 #include "content/public/test/mock_render_process_host.h"
 #include "content/public/test/test_renderer_host.h"
 #include "skia/ext/platform_canvas.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/skia/include/core/SkColorPriv.h"
 #include "ui/gfx/canvas.h"
+#include "ui/gfx/geometry/size_conversions.h"
 #include "ui/surface/transport_dib.h"
 
 using content::WebContents;
 using thumbnails::SimpleThumbnailCrop;
 
 typedef testing::Test SimpleThumbnailCropTest;
 
 TEST_F(SimpleThumbnailCropTest, GetClippedBitmap_TallerThanWide) {
   // The input bitmap is vertically long.
   gfx::Canvas canvas(gfx::Size(40, 90), 1.0f, true);
@@ skipping 74 matching lines @@
       bitmap, 20, 10, &clip_result);
   // The clipped bitmap should have the same aspect ratio of the desired size.
   EXPECT_EQ(40, clipped_bitmap.width());
   EXPECT_EQ(20, clipped_bitmap.height());
   // The input was taller than wide.
   EXPECT_EQ(thumbnails::CLIP_RESULT_TALLER_THAN_WIDE, clip_result);
 }
 
 TEST_F(SimpleThumbnailCropTest, GetCanvasCopyInfo) {
   gfx::Size thumbnail_size(200, 120);
+  gfx::Size expected_2x_size =
+      gfx::ToFlooredSize(gfx::ScaleSize(thumbnail_size, 2.0));
   float desired_aspect =
       static_cast<float>(thumbnail_size.width()) / thumbnail_size.height();
   scoped_refptr<thumbnails::ThumbnailingAlgorithm> algorithm(
       new SimpleThumbnailCrop(thumbnail_size));
   gfx::Rect clipping_rect_result;
   gfx::Size target_size_result;
 
   thumbnails::ClipResult clip_result = algorithm->GetCanvasCopyInfo(
       gfx::Size(400, 210),
       ui::SCALE_FACTOR_200P,
       &clipping_rect_result,
       &target_size_result);
   gfx::Size clipping_size = clipping_rect_result.size();
   float clip_aspect =
       static_cast<float>(clipping_size.width()) / clipping_size.height();
   EXPECT_EQ(thumbnails::CLIP_RESULT_WIDER_THAN_TALL, clip_result);
-  EXPECT_EQ(thumbnail_size, target_size_result);
+  EXPECT_EQ(expected_2x_size, target_size_result);
   EXPECT_NEAR(desired_aspect, clip_aspect, 0.01);
 
   clip_result = algorithm->GetCanvasCopyInfo(
       gfx::Size(600, 200),
       ui::SCALE_FACTOR_200P,
       &clipping_rect_result,
       &target_size_result);
   clipping_size = clipping_rect_result.size();
   clip_aspect =
       static_cast<float>(clipping_size.width()) / clipping_size.height();
   EXPECT_EQ(thumbnails::CLIP_RESULT_MUCH_WIDER_THAN_TALL, clip_result);
-  EXPECT_EQ(thumbnail_size, target_size_result);
+  EXPECT_EQ(expected_2x_size, target_size_result);
   EXPECT_NEAR(desired_aspect, clip_aspect, 0.01);
 
   clip_result = algorithm->GetCanvasCopyInfo(
       gfx::Size(300, 600),
       ui::SCALE_FACTOR_200P,
       &clipping_rect_result,
       &target_size_result);
   clipping_size = clipping_rect_result.size();
   clip_aspect =
       static_cast<float>(clipping_size.width()) / clipping_size.height();
   EXPECT_EQ(thumbnails::CLIP_RESULT_TALLER_THAN_WIDE, clip_result);
-  EXPECT_EQ(thumbnail_size, target_size_result);
+  EXPECT_EQ(expected_2x_size, target_size_result);
   EXPECT_NEAR(desired_aspect, clip_aspect, 0.01);
 
   clip_result = algorithm->GetCanvasCopyInfo(
       gfx::Size(200, 100),
       ui::SCALE_FACTOR_200P,
       &clipping_rect_result,
       &target_size_result);
   EXPECT_EQ(thumbnails::CLIP_RESULT_SOURCE_IS_SMALLER, clip_result);
-  EXPECT_EQ(thumbnail_size, target_size_result);
+  EXPECT_EQ(expected_2x_size, target_size_result);
+}
+
+TEST_F(SimpleThumbnailCropTest, GetCanvasCopyInfoDifferentScales) {
+  gfx::Size thumbnail_size(200, 120);
+  scoped_refptr<thumbnails::ThumbnailingAlgorithm> algorithm(
+      new SimpleThumbnailCrop(thumbnail_size));
+
+  gfx::Rect clipping_rect_result;
+  gfx::Size target_size_result;
+
+  gfx::Size expected_2x_size =
+      gfx::ToFlooredSize(gfx::ScaleSize(thumbnail_size, 2.0));
+
+  // Test at 1x scale. Expect a 2x thumbnail (we do this for quality).
+  algorithm->GetCanvasCopyInfo(gfx::Size(400, 210), ui::SCALE_FACTOR_100P,
+                               &clipping_rect_result, &target_size_result);
+  EXPECT_EQ(expected_2x_size, target_size_result);
+
+  // Test at 2x scale.
+  algorithm->GetCanvasCopyInfo(gfx::Size(400, 210), ui::SCALE_FACTOR_200P,
+                               &clipping_rect_result, &target_size_result);
+  EXPECT_EQ(expected_2x_size, target_size_result);
+
+  // Test at 3x scale.
+  gfx::Size expected_3x_size =
+      gfx::ToFlooredSize(gfx::ScaleSize(thumbnail_size, 3.0));
+  algorithm->GetCanvasCopyInfo(gfx::Size(400, 210), ui::SCALE_FACTOR_300P,
+                               &clipping_rect_result, &target_size_result);
+  EXPECT_EQ(expected_3x_size, target_size_result);
 }
 
 TEST_F(SimpleThumbnailCropTest, GetClippingRect) {
   const gfx::Size desired_size(300, 200);
   thumbnails::ClipResult clip_result;
   // Try out 'microsource'.
   gfx::Rect clip_rect = SimpleThumbnailCrop::GetClippingRect(
       gfx::Size(300, 199), desired_size, &clip_result);
   EXPECT_EQ(thumbnails::CLIP_RESULT_SOURCE_IS_SMALLER, clip_result);
   EXPECT_EQ(gfx::Point(0, 0).ToString(), clip_rect.origin().ToString());
@@ skipping 15 matching lines @@
   EXPECT_LT(0, clip_rect.x());
   EXPECT_GE(2000, clip_rect.width());
   EXPECT_EQ(800, clip_rect.height());
 
   clip_rect = SimpleThumbnailCrop::GetClippingRect(
       gfx::Size(900, 600), desired_size, &clip_result);
   EXPECT_EQ(thumbnails::CLIP_RESULT_NOT_CLIPPED, clip_result);
   EXPECT_EQ(gfx::Point(0, 0).ToString(), clip_rect.origin().ToString());
   EXPECT_EQ(gfx::Size(900, 600).ToString(), clip_rect.size().ToString());
 }