Tab audio indicator: Tweak animation

chrome/browser/ui/tabs/tab_audio_indicator.cc

 // Copyright (c) 2013 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/ui/tabs/tab_audio_indicator.h"
 
 #include "grit/theme_resources.h"
 #include "ui/base/animation/animation_container.h"
 #include "ui/base/animation/linear_animation.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/skia_util.h"
 
 namespace {
 
 // The number of columns to draw for the equalizer graphic.
 const size_t kEqualizerColumnCount = 3;
 
 // The equalizer cycles between these frames. An equalizer frame is 2 columns
 // where each column ranges from 0 to 4.
 const size_t kEqualizerFrames[][kEqualizerColumnCount] = {
-  { 0, 1, 2 },
-  { 1, 2, 3 },
-  { 2, 3, 2 },
-  { 3, 2, 1 },
-  { 2, 1, 0 },
-  { 1, 0, 1 },
-  { 0, 1, 2 },
-  { 0, 0, 2 },
-  { 0, 0, 1 },
-  { 1, 0, 0 },
-  { 2, 1, 0 },
-  { 1, 0, 1 },
+   { 1, 1, 1 },
+   { 1, 2, 2 },
+   { 2, 2, 3 },
+   { 3, 3, 2 },
+   { 3, 2, 1 },
+   { 2, 1, 2 },
+   { 1, 2, 3 },
+   { 2, 1, 2 },
+   { 3, 2, 1 },
+   { 3, 2, 1 },
+   { 2, 3, 2 },
+   { 1, 2, 3 },
+   { 2, 1, 2 },
 };
 
 // The space between equalizer levels.
 const int kEqualizerColumnPadding = 1;
 
 // The duration of each equalizer frame.
-const size_t kAnimationCycleDurationMs = 300;
+const size_t kAnimationCycleDurationMs = 250;
 
 // The duration of the "ending" animation once audio stops playing.
 const size_t kAnimationEndingDurationMs = 1000;
 
 // Target frames per second. In reality fewer frames are drawn because the
 // equalizer levels change slowly.
 const int kFPS = 15;
 
 }  // namespace
 
@@ skipping 37 matching lines @@
 
   // Draw 3 equalizer columns. |IDR_AUDIO_EQUALIZER_COLUMN| is a column of the
   // equalizer with 4 levels. The current level is between 0 and 4 so the
   // image is shifted down and then drawn.
   if (state_ != STATE_NOT_ANIMATING) {
     ui::ResourceBundle& rb = ResourceBundle::GetSharedInstance();
     gfx::ImageSkia* image(rb.GetImageSkiaNamed(IDR_AUDIO_EQUALIZER_COLUMN));
     int x = rect.right();
     std::vector<int> levels = GetCurrentEqualizerLevels();
     for (int i = levels.size() - 1; i >= 0; --i) {
+      x -= image->width();
       if (levels[i] == 0)
         continue;
 
       // Shift the image down by the level.
       int y = rect.bottom() - levels[i] * 2;
-      x -= image->width();
       canvas->DrawImageInt(*image, x, y);
 
       // Clip the equalizer column so the favicon doesn't obscure it.
       gfx::Rect equalizer_rect(x, y, image->width(), image->height());
       canvas->sk_canvas()->clipRect(
           gfx::RectToSkRect(equalizer_rect), SkRegion::kDifference_Op);
 
       // Padding is baked into both sides of the icons so overlap the images.
       x += kEqualizerColumnPadding;
     }
@@ skipping 40 matching lines @@
   // level and the target equalizer level.
   for (size_t i = 0; i < kEqualizerColumnCount; ++i) {
     int start = kEqualizerFrames[frame_index_][i];
     int end = state_ == STATE_ANIMATION_ENDING
               ? 0
               : kEqualizerFrames[next_frame_index][i];
     levels.push_back(animation_->CurrentValueBetween(start, end));
   }
   return levels;
 }