GTK: Redo button tints in GTK+ mode.

Use separate tints for icons in the omnibox and the other icons like page/app menu. We don't pick the tinting color to be the skyline accent color, but instead create one based off the accent color and the contrast between the window background and the label color.

BUG=43853
TEST=1) Darklooks should have white icons (both the page icons and in the omnibox) 2) DarkRoom should have page/app menu icons that match the label color on the "Other Bookmarks" button while the icons in the omnibox which are on a white background should visually be more orange and contrast with the white. 3) Ambiance/Radiance should have icons that contrast with their background instead of fading into it. 4) New Wave should have dark rust orange instead of light neon orange (again, contrasting with the background).

Review URL: http://codereview.chromium.org/2266004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@48401 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 109 insertions, 25 deletions

diff --git a/chrome/browser/gtk/gtk_theme_provider.cc b/chrome/browser/gtk/gtk_theme_provider.cc
index 0f276d0..d107064 100644
--- a/chrome/browser/gtk/gtk_theme_provider.cc
+++ b/chrome/browser/gtk/gtk_theme_provider.cc
@@ -124,6 +124,69 @@ bool IsOverridableImage(int id) {
   return images.count(id) > 0;
 }
 
+// Picks a button tint from a set of background colors. While
+// |accent_gdk_color| will usually be the same color through a theme, this
+// function will get called with the normal GtkLabel |text_color|/GtkWindow
+// |background_color| pair and the GtkEntry |text_color|/|background_color|
+// pair. While 3/4 of the time the resulting tint will be the same, themes that
+// have a dark window background (with light text) and a light text entry (with
+// dark text) will get better icons with this separated out.
+void PickButtonTintFromColors(const GdkColor& accent_gdk_color,
+                              const GdkColor& text_color,
+                              const GdkColor& background_color,
+                              color_utils::HSL* tint) {
+  SkColor accent_color = GdkToSkColor(&accent_gdk_color);
+  color_utils::HSL accent_tint;
+  color_utils::SkColorToHSL(accent_color, &accent_tint);
+
+  color_utils::HSL text_tint;
+  color_utils::SkColorToHSL(GdkToSkColor(&text_color), &text_tint);
+
+  color_utils::HSL background_tint;
+  color_utils::SkColorToHSL(GdkToSkColor(&background_color), &background_tint);
+
+  // If the accent color is gray, then our normal HSL tomfoolery will bring out
+  // whatever color is oddly dominant (for example, in rgb space [125, 128,
+  // 125] will tint green instead of gray). Slight differences (+/-10 (4%) to
+  // all color components) should be interpreted as this color being gray and
+  // we should switch into a special grayscale mode.
+  int rb_diff = abs(SkColorGetR(accent_color) - SkColorGetB(accent_color));
+  int rg_diff = abs(SkColorGetR(accent_color) - SkColorGetG(accent_color));
+  int bg_diff = abs(SkColorGetB(accent_color) - SkColorGetG(accent_color));
+  if (rb_diff < 10 && rg_diff < 10 && bg_diff < 10) {
+    // Our accent is white/gray/black. Only the luminance of the accent color
+    // matters.
+    tint->h = -1;
+
+    // Use the saturation of the text.
+    tint->s = text_tint.s;
+
+    // Use the luminance of the accent color UNLESS there isn't enough
+    // luminance contrast between the accent color and the base color.
+    if (fabs(accent_tint.l - background_tint.l) > 0.3)
+      tint->l = accent_tint.l;
+    else
+      tint->l = text_tint.l;
+  } else {
+    // Our accent is a color.
+    tint->h = accent_tint.h;
+
+    // Don't modify the saturation; the amount of color doesn't matter.
+    tint->s = -1;
+
+    // If the text wants us to darken the icon, don't change the luminance (the
+    // icons are already dark enough). Otherwise, lighten the icon by no more
+    // than 0.9 since we don't want a pure-white icon even if the text is pure
+    // white.
+    if (text_tint.l < 0.5)
+      tint->l = -1;
+    else if (text_tint.l <= 0.9)
+      tint->l = text_tint.l;
+    else
+      tint->l = 0.9;
+  }
+}
+
 }  // namespace
 
 GtkWidget* GtkThemeProvider::icon_widget_ = NULL;
@@ -507,7 +570,7 @@ void GtkThemeProvider::LoadGtkValues() {
 
   GtkStyle* window_style = gtk_rc_get_style(fake_window_);
   GdkColor toolbar_color = window_style->bg[GTK_STATE_NORMAL];
-  GdkColor button_color = window_style->fg[GTK_STATE_NORMAL];
+  GdkColor button_color = window_style->bg[GTK_STATE_SELECTED];
 
   GtkStyle* label_style = gtk_rc_get_style(fake_label_.get());
   GdkColor label_color = label_style->fg[GTK_STATE_NORMAL];
@@ -548,6 +611,11 @@ void GtkThemeProvider::LoadGtkValues() {
     frame_color.blue = SkColorGetB(shifted) * kSkiaToGDKMultiplier;
   }
 
+  // Build the various icon tints.
+  GetNormalButtonTintHSL(&button_tint_);
+  GetNormalEntryForegroundHSL(&entry_tint_);
+  GetSelectedEntryForegroundHSL(&selected_entry_tint_);
+
   SetThemeTintFromGtk(BrowserThemeProvider::TINT_BUTTONS, &button_color);
   SetThemeTintFromGtk(BrowserThemeProvider::TINT_FRAME, &frame_color);
   SetThemeTintFromGtk(BrowserThemeProvider::TINT_FRAME_INCOGNITO, &frame_color);
@@ -748,9 +816,7 @@ SkBitmap* GtkThemeProvider::GenerateGtkThemeBitmap(int id) const {
     case IDR_OMNIBOX_STAR:
     case IDR_GEOLOCATION_ALLOWED_LOCATIONBAR_ICON:
     case IDR_GEOLOCATION_DENIED_LOCATIONBAR_ICON: {
-      color_utils::HSL tint;
-      GetNormalEntryForegroundHSL(&tint);
-      return GenerateTintedIcon(id, tint);
+      return GenerateTintedIcon(id, entry_tint_);
     }
     // Two sets of omnibox icons, the one for normal http and the one for
     // history, include white backgrounds (and are supposed to, for the windows
@@ -758,41 +824,30 @@ SkBitmap* GtkThemeProvider::GenerateGtkThemeBitmap(int id) const {
     // color combinations we need to deal with, switch them out with
     // transparent background versions.
     case IDR_OMNIBOX_HTTP: {
-      color_utils::HSL tint;
-      GetNormalEntryForegroundHSL(&tint);
-      return GenerateTintedIcon(IDR_OMNIBOX_HTTP_TRANSPARENT, tint);
+      return GenerateTintedIcon(IDR_OMNIBOX_HTTP_TRANSPARENT, entry_tint_);
     }
     case IDR_OMNIBOX_HISTORY: {
-      color_utils::HSL tint;
-      GetNormalEntryForegroundHSL(&tint);
-      return GenerateTintedIcon(IDR_OMNIBOX_HISTORY_TRANSPARENT, tint);
+      return GenerateTintedIcon(IDR_OMNIBOX_HISTORY_TRANSPARENT, entry_tint_);
     }
     // In GTK mode, the dark versions of the omnibox icons only ever appear in
     // the autocomplete popup and only against the current theme's GtkEntry
     // base[GTK_STATE_SELECTED] color, so tint the icons so they won't collide
     // with the selected color.
     case IDR_OMNIBOX_HTTP_DARK: {
-      color_utils::HSL tint;
-      GetSelectedEntryForegroundHSL(&tint);
-      return GenerateTintedIcon(IDR_OMNIBOX_HTTP_DARK_TRANSPARENT, tint);
+      return GenerateTintedIcon(IDR_OMNIBOX_HTTP_DARK_TRANSPARENT,
+                                selected_entry_tint_);
     }
     case IDR_OMNIBOX_HISTORY_DARK: {
-      color_utils::HSL tint;
-      GetSelectedEntryForegroundHSL(&tint);
-      return GenerateTintedIcon(IDR_OMNIBOX_HISTORY_DARK_TRANSPARENT, tint);
+      return GenerateTintedIcon(IDR_OMNIBOX_HISTORY_DARK_TRANSPARENT,
+                                selected_entry_tint_);
     }
     case IDR_OMNIBOX_SEARCH_DARK:
     case IDR_OMNIBOX_MORE_DARK:
     case IDR_OMNIBOX_STAR_DARK: {
-      color_utils::HSL tint;
-      GetSelectedEntryForegroundHSL(&tint);
-      return GenerateTintedIcon(id, tint);
+      return GenerateTintedIcon(id, selected_entry_tint_);
     }
     default: {
-      TintMap::const_iterator it = tints_.find(
-          BrowserThemeProvider::TINT_BUTTONS);
-      DCHECK(it != tints_.end());
-      return GenerateTintedIcon(id, it->second);
+      return GenerateTintedIcon(id, button_tint_);
     }
   }
 }
@@ -822,15 +877,35 @@ SkBitmap* GtkThemeProvider::GenerateTintedIcon(int base_id,
       *button, tint));
 }
 
+void GtkThemeProvider::GetNormalButtonTintHSL(
+    color_utils::HSL* tint) const {
+  GtkStyle* window_style = gtk_rc_get_style(fake_window_);
+  const GdkColor accent_gdk_color = window_style->bg[GTK_STATE_SELECTED];
+  const GdkColor base_color = window_style->base[GTK_STATE_NORMAL];
+
+  GtkStyle* label_style = gtk_rc_get_style(fake_label_.get());
+  const GdkColor text_color = label_style->fg[GTK_STATE_NORMAL];
+
+  PickButtonTintFromColors(accent_gdk_color, text_color, base_color, tint);
+}
+
 void GtkThemeProvider::GetNormalEntryForegroundHSL(
     color_utils::HSL* tint) const {
+  GtkStyle* window_style = gtk_rc_get_style(fake_window_);
+  const GdkColor accent_gdk_color = window_style->bg[GTK_STATE_SELECTED];
+
   GtkStyle* style = gtk_rc_get_style(fake_entry_.get());
-  const GdkColor color = style->text[GTK_STATE_NORMAL];
-  color_utils::SkColorToHSL(GdkToSkColor(&color), tint);
+  const GdkColor text_color = style->text[GTK_STATE_NORMAL];
+  const GdkColor base_color = style->base[GTK_STATE_NORMAL];
+
+  PickButtonTintFromColors(accent_gdk_color, text_color, base_color, tint);
 }
 
 void GtkThemeProvider::GetSelectedEntryForegroundHSL(
     color_utils::HSL* tint) const {
+  // The simplest of all the tints. We just use the selected text in the entry
+  // since the icons tinted this way will only be displayed against
+  // base[GTK_STATE_SELECTED].
   GtkStyle* style = gtk_rc_get_style(fake_entry_.get());
   const GdkColor color = style->text[GTK_STATE_SELECTED];
   color_utils::SkColorToHSL(GdkToSkColor(&color), tint);
diff --git a/chrome/browser/gtk/gtk_theme_provider.h b/chrome/browser/gtk/gtk_theme_provider.h
index 64a4c65..17059bb 100644
--- a/chrome/browser/gtk/gtk_theme_provider.h
+++ b/chrome/browser/gtk/gtk_theme_provider.h
@@ -167,6 +167,10 @@ class GtkThemeProvider : public BrowserThemeProvider,
   // Tints an icon based on tint.
   SkBitmap* GenerateTintedIcon(int base_id, color_utils::HSL tint) const;
 
+  // Returns the tint for buttons that contrasts with the normal window
+  // background color.
+  void GetNormalButtonTintHSL(color_utils::HSL* tint) const;
+
   // Returns a tint that's the color of the current normal text in an entry.
   void GetNormalEntryForegroundHSL(color_utils::HSL* tint) const;
 
@@ -203,6 +207,11 @@ class GtkThemeProvider : public BrowserThemeProvider,
   ColorMap colors_;
   TintMap tints_;
 
+  // Colors used to tint certain icons.
+  color_utils::HSL button_tint_;
+  color_utils::HSL entry_tint_;
+  color_utils::HSL selected_entry_tint_;
+
   // Colors that we pass to WebKit. These are generated each time the theme
   // changes.
   SkColor focus_ring_color_;