Improve large tab strip by leveraging touch icons when present

chrome/browser/ui/touch/tabs/touch_tab.cc

Index: chrome/browser/ui/touch/tabs/touch_tab.cc
diff --git a/chrome/browser/ui/touch/tabs/touch_tab.cc b/chrome/browser/ui/touch/tabs/touch_tab.cc
index dca408a783e84522e451556d230f89f5d80e80a8..f445eedf21984f609477d7a91ace4be867ae2a76 100644
--- a/chrome/browser/ui/touch/tabs/touch_tab.cc
+++ b/chrome/browser/ui/touch/tabs/touch_tab.cc
@@ -9,6 +9,7 @@
 #include "grit/app_resources.h"
 #include "grit/theme_resources.h"
 #include "grit/theme_resources_standard.h"
+#include "skia/ext/image_operations.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/favicon_size.h"
@@ -19,10 +20,6 @@ static const int kLeftPadding = 16;
 static const int kRightPadding = 15;
 static const int kDropShadowHeight = 2;
 
-// The size of the favicon touch area. This generally would be the same as
-// kFaviconSize in ui/gfx/favicon_size.h
-static const int kTouchTabIconSize = 32;
-
 TouchTab::TouchTabImage TouchTab::tab_alpha = {0};
 TouchTab::TouchTabImage TouchTab::tab_active = {0};
 TouchTab::TouchTabImage TouchTab::tab_inactive = {0};
@@ -180,7 +177,6 @@ void TouchTab::PaintActiveTabBackground(gfx::Canvas* canvas) {
 }
 
 void TouchTab::PaintIcon(gfx::Canvas* canvas) {
-  // TODO(wyck): use thumbnailer to get better page images
   int x = favicon_bounds_.x();
   int y = favicon_bounds_.y();
 
@@ -190,23 +186,19 @@ void TouchTab::PaintIcon(gfx::Canvas* canvas) {
   x += x_base;
 
   if (base::i18n::IsRTL()) {
-    x = width() - x -
-        (data().favicon.isNull() ? kFaviconSize : data().favicon.width());
+    x = width() - x - (data().favicon.isNull()
+        ? kTouchTargetIconSize : data().favicon.width());
   }
 
-  int favicon_x = x;
-  if (!data().favicon.isNull() && data().favicon.width() != kFaviconSize)
-    favicon_x += (data().favicon.width() - kFaviconSize) / 2;
-
   if (data().network_state != TabRendererData::NETWORK_STATE_NONE) {
     ui::ThemeProvider* tp = GetThemeProvider();
     SkBitmap frames(*tp->GetBitmapNamed(
-        (data().network_state == TabRendererData::NETWORK_STATE_WAITING) ?
-        IDR_THROBBER_WAITING : IDR_THROBBER));
+        (data().network_state == TabRendererData::NETWORK_STATE_WAITING)
+                ? IDR_THROBBER_WAITING : IDR_THROBBER));
     int image_size = frames.height();
     int image_offset = loading_animation_frame() * image_size;
-    canvas->DrawBitmapInt(frames, image_offset, 0, image_size, image_size, x, y,
-                          kTouchTabIconSize, kTouchTabIconSize, false);
+    canvas->DrawBitmapInt(frames, image_offset, 0, image_size, image_size, x,
+        y, kTouchTargetIconSize, kTouchTargetIconSize, false);
   } else {
     canvas->Save();
     canvas->ClipRectInt(0, 0, width(), height());
@@ -215,32 +207,25 @@ void TouchTab::PaintIcon(gfx::Canvas* canvas) {
       SkBitmap crashed_favicon(*rb.GetBitmapNamed(IDR_SAD_FAVICON));
       canvas->DrawBitmapInt(crashed_favicon, 0, 0, crashed_favicon.width(),
           crashed_favicon.height(), x, y + favicon_hiding_offset(),
-          kTouchTabIconSize, kTouchTabIconSize, true);
+          kTouchTargetIconSize, kTouchTargetIconSize, true);
     } else {
       if (!data().favicon.isNull()) {
-
-        if ((data().favicon.width() == kTouchTabIconSize) &&
-            (data().favicon.height() == kTouchTabIconSize)) {
-          canvas->DrawBitmapInt(data().favicon, 0, 0,
-                                data().favicon.width(), data().favicon.height(),
-                                x, y + favicon_hiding_offset(),
-                                kTouchTabIconSize, kTouchTabIconSize, true);
+        // At this stage small favicons (16x16) are copied from NavigationEntry
+        // and need to be scaled every time, touch icons on the other hand
+        // should have been rescaled properly (to 32x32) in method:
+        // TouchTabStripController::OnTouchIconAvailable().
+        if (data().favicon.width() == kFaviconSize
+            && data().favicon.height() == kFaviconSize) {

[sky, 2011/06/16 15:43:41]

&& should be on the previous line.
Also, you should change SetTabRendererDataFromModel to scale the image there.
That way, you only scale once no matter how many times you might end up
painting.

[Emmanuel Saint-loubert-Bié, 2011/06/17 00:01:44]

Done.

+          SkBitmap scaled_image = skia::ImageOperations::Resize(data().favicon,
+              skia::ImageOperations::RESIZE_BEST, kTouchTargetIconSize,
+              kTouchTargetIconSize);
+          canvas->DrawBitmapInt(scaled_image, 0, 0, kTouchTargetIconSize,
+              kTouchTargetIconSize, x, y + favicon_hiding_offset(),
+              kTouchTargetIconSize, kTouchTargetIconSize, true);
         } else {
-          // Draw a background around target touch area in case the favicon
-          // is smaller than touch area (e.g www.google.com is 16x16 now)
-          canvas->DrawRectInt(
-              GetThemeProvider()->GetColor(
-                  ThemeService::COLOR_BUTTON_BACKGROUND),
-              x, y, kTouchTabIconSize, kTouchTabIconSize);
-
-          // We center the image
-          // TODO(saintlou): later request larger image from HistoryService
           canvas->DrawBitmapInt(data().favicon, 0, 0, data().favicon.width(),
-              data().favicon.height(),
-              x + ((kTouchTabIconSize - data().favicon.width()) / 2),
-              y + ((kTouchTabIconSize - data().favicon.height()) / 2) +
-                                                     favicon_hiding_offset(),
-              data().favicon.width(), data().favicon.height(), true);
+              data().favicon.height(), x, y + favicon_hiding_offset(),
+              kTouchTargetIconSize, kTouchTargetIconSize, true);
         }
       }
     }
@@ -260,7 +245,6 @@ void TouchTab::InitTabResources() {
   LoadTabImages();
 }
 
-
 // static
 void TouchTab::LoadTabImages() {
   // We're not letting people override tab images just yet.