Dramatically simplify view painting by getting rid of RootView's redundant knowledge of invalid rects.The OS is capable of doing this for us (see: InvalidateRect, etc.), so we should just defer to it.I was also able to remove all of the custom logic in WindowWin::OnNCPaint and replace it with a simple SetMsgHandled check.http://crbug.com/72040TEST=none

Review URL: http://codereview.chromium.org/6469096

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@75758 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 5 insertions, 116 deletions

diff --git a/views/window/window_win.cc b/views/window/window_win.cc
index be578834..239226d 100644
--- a/views/window/window_win.cc
+++ b/views/window/window_win.cc
@@ -854,18 +854,11 @@ void WindowWin::OnMouseLeave() {
 LRESULT WindowWin::OnNCActivate(BOOL active) {
   is_active_ = !!active;
 
-  // We need to force a synchronous repaint, otherwise we'll be left in the
-  // wrong activation state until something else causes a repaint later.
-  // Both the native and non-native frames may render activation-state
-  // dependent UI.
+  // The frame may need to redraw as a result of the activation change.
   // We can get WM_NCACTIVATE before we're actually visible. If we're not
   // visible, no need to paint.
-  if (IsWindowVisible(GetNativeView())) {
+  if (IsVisible())
     non_client_view_->SchedulePaint();
-    // We need to force a paint now, as a user dragging a window will block
-    // painting operations while the move is in progress.
-    PaintNow(root_view_->GetScheduledPaintRect());
-  }
 
   // If we're active again, we should be allowed to render as inactive, so
   // tell the non-client view. This must be done independently of the check for
@@ -976,114 +969,10 @@ LRESULT WindowWin::OnNCHitTest(const CPoint& point) {
   return WidgetWin::OnNCHitTest(point);
 }
 
-namespace {
-struct ClipState {
-  // The window being painted.
-  HWND parent;
-
-  // DC painting to.
-  HDC dc;
-
-  // Origin of the window in terms of the screen.
-  int x;
-  int y;
-};
-
-// See comments in OnNCPaint for details of this function.
-static BOOL CALLBACK ClipDCToChild(HWND window, LPARAM param) {
-  ClipState* clip_state = reinterpret_cast<ClipState*>(param);
-  if (GetParent(window) == clip_state->parent && IsWindowVisible(window)) {
-    RECT bounds;
-    GetWindowRect(window, &bounds);
-    ExcludeClipRect(clip_state->dc,
-                    bounds.left - clip_state->x,
-                    bounds.top - clip_state->y,
-                    bounds.right - clip_state->x,
-                    bounds.bottom - clip_state->y);
-  }
-  return TRUE;
-}
-}  // namespace
-
 void WindowWin::OnNCPaint(HRGN rgn) {
-  // We only do non-client painting if we're not using the native frame.
-  // It's required to avoid some native painting artifacts from appearing when
-  // the window is resized.
-  if (non_client_view_->UseNativeFrame()) {
-    WidgetWin::OnNCPaint(rgn);
-    return;
-  }
-
-  // We have an NC region and need to paint it. We expand the NC region to
-  // include the dirty region of the root view. This is done to minimize
-  // paints.
-  CRect window_rect;
-  GetWindowRect(&window_rect);
-
-  if (window_rect.Width() != root_view_->width() ||
-      window_rect.Height() != root_view_->height()) {
-    // If the size of the window differs from the size of the root view it
-    // means we're being asked to paint before we've gotten a WM_SIZE. This can
-    // happen when the user is interactively resizing the window. To avoid
-    // mass flickering we don't do anything here. Once we get the WM_SIZE we'll
-    // reset the region of the window which triggers another WM_NCPAINT and
-    // all is well.
-    return;
-  }
-
-  CRect dirty_region;
-  // A value of 1 indicates paint all.
-  if (!rgn || rgn == reinterpret_cast<HRGN>(1)) {
-    dirty_region = CRect(0, 0, window_rect.Width(), window_rect.Height());
-  } else {
-    RECT rgn_bounding_box;
-    GetRgnBox(rgn, &rgn_bounding_box);
-    if (!IntersectRect(&dirty_region, &rgn_bounding_box, &window_rect))
-      return;  // Dirty region doesn't intersect window bounds, bale.
-
-    // rgn_bounding_box is in screen coordinates. Map it to window coordinates.
-    OffsetRect(&dirty_region, -window_rect.left, -window_rect.top);
-  }
-
-  // In theory GetDCEx should do what we want, but I couldn't get it to work.
-  // In particular the docs mentiond DCX_CLIPCHILDREN, but as far as I can tell
-  // it doesn't work at all. So, instead we get the DC for the window then
-  // manually clip out the children.
-  HDC dc = GetWindowDC(GetNativeView());
-  ClipState clip_state;
-  clip_state.x = window_rect.left;
-  clip_state.y = window_rect.top;
-  clip_state.parent = GetNativeView();
-  clip_state.dc = dc;
-  EnumChildWindows(GetNativeView(), &ClipDCToChild,
-                   reinterpret_cast<LPARAM>(&clip_state));
-
-  RootView* root_view = GetRootView();
-  gfx::Rect old_paint_region =
-      root_view->GetScheduledPaintRectConstrainedToSize();
-
-  if (!old_paint_region.IsEmpty()) {
-    // The root view has a region that needs to be painted. Include it in the
-    // region we're going to paint.
-
-    CRect old_paint_region_crect = old_paint_region.ToRECT();
-    CRect tmp = dirty_region;
-    UnionRect(&dirty_region, &tmp, &old_paint_region_crect);
-  }
-
-  root_view->SchedulePaintInRect(gfx::Rect(dirty_region), false);
-
-  // gfx::CanvasSkiaPaint's destructor does the actual painting. As such, wrap
-  // the following in a block to force paint to occur so that we can release
-  // the dc.
-  {
-    gfx::CanvasSkiaPaint canvas(dc, opaque(), dirty_region.left,
-                                dirty_region.top, dirty_region.Width(),
-                                dirty_region.Height());
-    root_view->Paint(&canvas);
-  }
-
-  ReleaseDC(GetNativeView(), dc);
+  // When using a custom frame, we want to avoid calling DefWindowProc() since
+  // that may render artifacts.
+  SetMsgHandled(!non_client_view_->UseNativeFrame());
 }
 
 void WindowWin::OnNCLButtonDown(UINT ht_component, const CPoint& point) {