Hiroyuki Ikezoe (:hiro) Assignee
	Description • 6 years ago

      No description provided.

	Hiroyuki Ikezoe (:hiro) Assignee
	Comment 5 • 6 years ago

Comment on attachment 9037122 [details] [diff] [review]
Use the layout viewport size for position:fixed elements

># HG changeset patch
># Parent  56d6aff822a5376e149fcc03c0f2a961c891ccf3
>Bug 1516377 - Use the layout viewport for position:fixed elements. r?botond
>
>diff --git a/layout/base/PresShell.cpp b/layout/base/PresShell.cpp
>--- a/layout/base/PresShell.cpp
>+++ b/layout/base/PresShell.cpp
>@@ -10119,6 +10119,14 @@ nsPoint nsIPresShell::GetLayoutViewportO
>   return result;
> }
> 
>+nsSize nsIPresShell::GetLayoutViewportSize() const {
>+  nsSize result;
>+  if (nsIScrollableFrame* sf = GetRootScrollFrameAsScrollable()) {
>+    result = sf->GetScrollPortRect().Size();
>+  }
>+  return result;
>+}
>+
> void nsIPresShell::RecomputeFontSizeInflationEnabled() {
>   mFontSizeInflationEnabled = DetermineFontSizeInflationState();
> 
>diff --git a/layout/base/nsIPresShell.h b/layout/base/nsIPresShell.h
>--- a/layout/base/nsIPresShell.h
>+++ b/layout/base/nsIPresShell.h
>@@ -1696,6 +1696,7 @@ class nsIPresShell : public nsStubDocume
>   }
> 
>   nsPoint GetLayoutViewportOffset() const;
>+  nsSize GetLayoutViewportSize() const;
> 
>   virtual void WindowSizeMoveDone() = 0;
>   virtual void SysColorChanged() = 0;
>diff --git a/layout/generic/ViewportFrame.cpp b/layout/generic/ViewportFrame.cpp
>--- a/layout/generic/ViewportFrame.cpp
>+++ b/layout/generic/ViewportFrame.cpp
>@@ -258,15 +258,20 @@ nsRect ViewportFrame::AdjustReflowInputA
>                "We don't handle correct positioning of fixed frames with "
>                "scrollbars in odd positions");
> 
>-  // Layout fixed position elements to the visual viewport size if and only if
>+  // Layout fixed position elements to the layout viewport size if and only if
>   // it has been set and it is larger than the computed size, otherwise use the
>   // computed size.
>   nsRect rect(0, 0, aReflowInput->ComputedWidth(),
>               aReflowInput->ComputedHeight());
>   nsIPresShell* ps = PresShell();
>-  if (ps->IsVisualViewportSizeSet() &&
>-      rect.Size() < ps->GetVisualViewportSize()) {
>-    rect.SizeTo(ps->GetVisualViewportSize());
>+  if (ps->IsVisualViewportSizeSet()) {
>+    if (rect.Size() < ps->GetVisualViewportSize()) {
>+      rect.SizeTo(ps->GetVisualViewportSize());
>+    }
>+    nsSize layoutViewportSize = ps->GetLayoutViewportSize();
>+    if (rect.Size() < layoutViewportSize) {
>+      rect.SizeTo(layoutViewportSize);
>+    }
>   }
>   return rect;
> }
>diff --git a/layout/painting/nsDisplayList.cpp b/layout/painting/nsDisplayList.cpp
>--- a/layout/painting/nsDisplayList.cpp
>+++ b/layout/painting/nsDisplayList.cpp
>@@ -969,11 +969,16 @@ nsDisplayListBuilder::OutOfFlowDisplayDa
>         nsRect(nsPoint(0, 0), aFrame->GetParent()->GetSize());
> 
>     nsIPresShell* ps = aFrame->PresShell();
>-    if (ps->IsVisualViewportSizeSet() &&
>-        dirtyRectRelativeToDirtyFrame.Size() < ps->GetVisualViewportSize()) {
>-      dirtyRectRelativeToDirtyFrame.SizeTo(ps->GetVisualViewportSize());
>-    }
>-
>+    if (ps->IsVisualViewportSizeSet()) {
>+      if (dirtyRectRelativeToDirtyFrame.Size() < ps->GetVisualViewportSize()) {
>+        dirtyRectRelativeToDirtyFrame.SizeTo(ps->GetVisualViewportSize());
>+      }
>+
>+      nsSize layoutViewportSize = ps->GetLayoutViewportSize();
>+      if (dirtyRectRelativeToDirtyFrame.Size() < layoutViewportSize) {
>+        dirtyRectRelativeToDirtyFrame.SizeTo(layoutViewportSize);
>+      }
>+    }
>     visible = dirtyRectRelativeToDirtyFrame;
>   }
> #endif

	Pulsebot
	Comment 8 • 6 years ago

Pushed by hikezoe@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/96d77e9c3f29
Use the layout viewport for position:fixed elements if the viewport is larger than. r=botond