Remove NativeThemeWin::PaintIndirect

ui/native_theme/native_theme_win.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 "ui/native_theme/native_theme_win.h"
 
 #include <windows.h>
 #include <stddef.h>
 #include <uxtheme.h>
 #include <vsstyle.h>
 #include <vssym32.h>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/win/scoped_gdi_object.h"
 #include "base/win/scoped_hdc.h"
 #include "base/win/scoped_select_object.h"
 #include "base/win/windows_version.h"
 #include "skia/ext/bitmap_platform_device.h"
 #include "skia/ext/platform_canvas.h"
 #include "skia/ext/skia_utils_win.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkColorPriv.h"

[Peter Kasting, 2016/06/29 23:20:01]

Maybe can remove this #include now?

 #include "third_party/skia/include/core/SkRefCnt.h"
 #include "third_party/skia/include/core/SkShader.h"
 #include "ui/base/material_design/material_design_controller.h"
 #include "ui/display/win/dpi.h"
 #include "ui/gfx/color_palette.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/gdi_util.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/skia_util.h"
@@ skipping 213 matching lines @@
       PaintMenuBackground(canvas, rect);
       return;
     case kMenuItemBackground:
       CommonThemePaintMenuItemBackground(this, canvas, state, rect,
                                          extra.menu_item);
       return;
     default:
       break;
   }
 
-  bool needs_paint_indirect = false;
-  if (!skia::SupportsPlatformPaint(canvas)) {
-    // This block will only get hit with --enable-accelerated-drawing flag.
-    needs_paint_indirect = true;
-  } else {
-    // Scrollbar components on Windows Classic theme (on all Windows versions)
-    // have particularly problematic alpha values, so always draw them
-    // indirectly. In addition, scrollbar thumbs and grippers for the Windows XP
-    // theme (available only on Windows XP) also need their alpha values
-    // fixed.
-    switch (part) {
-      case kScrollbarDownArrow:
-      case kScrollbarUpArrow:
-      case kScrollbarLeftArrow:
-      case kScrollbarRightArrow:
-        needs_paint_indirect = !GetThemeHandle(SCROLLBAR);
-        break;
-      case kScrollbarHorizontalThumb:
-      case kScrollbarVerticalThumb:
-      case kScrollbarHorizontalGripper:
-      case kScrollbarVerticalGripper:
-        needs_paint_indirect = !GetThemeHandle(SCROLLBAR) ||
-            base::win::GetVersion() == base::win::VERSION_XP;
-        break;
-      default:
-        break;
-    }
-  }
-
-  if (needs_paint_indirect)
-    PaintIndirect(canvas, part, state, rect, extra);
-  else
-    PaintDirect(canvas, part, state, rect, extra);
+  PaintDirect(canvas, part, state, rect, extra);

[Peter Kasting, 2016/06/29 23:20:01]

This is now the only caller of this function.  I would combine the two into one
function.

This should allow eliminating all the handling code in that function for the
four cases covered in the switch above, I believe.

 }
 
 NativeThemeWin::NativeThemeWin()
     : draw_theme_(NULL),
       draw_theme_ex_(NULL),
       get_theme_color_(NULL),
       get_theme_content_rect_(NULL),
       get_theme_part_size_(NULL),
       open_theme_(NULL),
       close_theme_(NULL),
@@ skipping 364 matching lines @@
       case NativeTheme::kColorId_CallToActionColor:
         return kCallToActionColorInvert;
       default:
         return color_utils::InvertColor(GetAuraColor(color_id, this));
     }
   }
 
   return GetAuraColor(color_id, this);
 }
 
-void NativeThemeWin::PaintIndirect(SkCanvas* canvas,
-                                   Part part,
-                                   State state,
-                                   const gfx::Rect& rect,
-                                   const ExtraParams& extra) const {
-  // TODO(asvitkine): This path is pretty inefficient - for each paint operation
-  //                  it creates a new offscreen bitmap Skia canvas. This can
-  //                  be sped up by doing it only once per part/state and
-  //                  keeping a cache of the resulting bitmaps.
-
-  // Create an offscreen canvas that is backed by an HDC.
-  sk_sp<skia::BitmapPlatformDevice> device(
-      skia::BitmapPlatformDevice::Create(
-          rect.width(), rect.height(), false, NULL));
-  DCHECK(device);
-  SkCanvas offscreen_canvas(device.get());
-  DCHECK(skia::SupportsPlatformPaint(&offscreen_canvas));
-
-  // Some of the Windows theme drawing operations do not write correct alpha
-  // values for fully-opaque pixels; instead the pixels get alpha 0. This is
-  // especially a problem on Windows XP or when using the Classic theme.
-  //
-  // To work-around this, mark all pixels with a placeholder value, to detect
-  // which pixels get touched by the paint operation. After paint, set any
-  // pixels that have alpha 0 to opaque and placeholders to fully-transparent.
-  const SkColor placeholder = SkColorSetARGB(1, 0, 0, 0);
-  offscreen_canvas.clear(placeholder);
-
-  // Offset destination rects to have origin (0,0).
-  gfx::Rect adjusted_rect(rect.size());
-  ExtraParams adjusted_extra(extra);
-  switch (part) {
-    case kProgressBar:
-      adjusted_extra.progress_bar.value_rect_x = 0;
-      adjusted_extra.progress_bar.value_rect_y = 0;
-      break;
-    case kScrollbarHorizontalTrack:
-    case kScrollbarVerticalTrack:
-      adjusted_extra.scrollbar_track.track_x = 0;
-      adjusted_extra.scrollbar_track.track_y = 0;
-      break;
-    default:
-      break;
-  }
-  // Draw the theme controls using existing HDC-drawing code.
-  PaintDirect(&offscreen_canvas, part, state, adjusted_rect, adjusted_extra);
-
-  SkBitmap bitmap = skia::ReadPixels(&offscreen_canvas);
-
-  // Post-process the pixels to fix up the alpha values (see big comment above).
-  const SkPMColor placeholder_value = SkPreMultiplyColor(placeholder);
-  const int pixel_count = rect.width() * rect.height();
-  SkPMColor* pixels = bitmap.getAddr32(0, 0);
-  for (int i = 0; i < pixel_count; i++) {
-    if (pixels[i] == placeholder_value) {
-      // Pixel wasn't touched - make it fully transparent.
-      pixels[i] = SkPackARGB32(0, 0, 0, 0);
-    } else if (SkGetPackedA32(pixels[i]) == 0) {
-      // Pixel was touched but has incorrect alpha of 0, make it fully opaque.
-      pixels[i] = SkPackARGB32(0xFF,
-                               SkGetPackedR32(pixels[i]),
-                               SkGetPackedG32(pixels[i]),
-                               SkGetPackedB32(pixels[i]));
-    }
-  }
-
-  // Draw the offscreen bitmap to the destination canvas.
-  canvas->drawBitmap(bitmap, rect.x(), rect.y());
-}
-
 HRESULT NativeThemeWin::GetThemePartSize(ThemeName theme_name,
                                          HDC hdc,
                                          int part_id,
                                          int state_id,
                                          RECT* rect,
                                          int ts,
                                          SIZE* size) const {
   HANDLE handle = GetThemeHandle(theme_name);
   return (handle && get_theme_part_size_) ?
       get_theme_part_size_(handle, hdc, part_id, state_id, rect, ts, size) :
@@ skipping 1324 matching lines @@
     break;
   case LAST:
     NOTREACHED();
     break;
   }
   theme_handles_[theme_name] = handle;
   return handle;
 }
 
 }  // namespace ui