forked from mirrors/gecko-dev
b5c12882f6
It's no longer used since https://hg.mozilla.org/mozilla-central/rev/c55ab6afe5ad . Depends on D19289 Differential Revision: https://phabricator.services.mozilla.com/D19290 --HG-- extra : moz-landing-system : lando
42 lines
1.6 KiB
C++
42 lines
1.6 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#ifndef mozilla_layout_ScrollSnap_h_
|
|
#define mozilla_layout_ScrollSnap_h_
|
|
|
|
#include "mozilla/Maybe.h"
|
|
#include "nsIScrollableFrame.h"
|
|
|
|
namespace mozilla {
|
|
|
|
namespace layers {
|
|
struct ScrollSnapInfo;
|
|
}
|
|
|
|
struct ScrollSnapUtils {
|
|
/**
|
|
* GetSnapPointForDestination determines which point to snap to after
|
|
* scrolling. |aStartPos| gives the position before scrolling and
|
|
* |aDestination| gives the position after scrolling, with no snapping.
|
|
* Behaviour is dependent on the value of |aUnit|.
|
|
* |aSnapInfo| and |aScrollRange| are characteristics of the scroll frame for
|
|
* which snapping is being performed.
|
|
* If a suitable snap point could be found, it is returned. Otherwise, an
|
|
* empty Maybe is returned.
|
|
* IMPORTANT NOTE: This function is designed to be called both on and off
|
|
* the main thread. If modifying its implementation, be sure
|
|
* not to touch main-thread-only data structures without
|
|
* appropriate locking.
|
|
*/
|
|
static mozilla::Maybe<nsPoint> GetSnapPointForDestination(
|
|
const layers::ScrollSnapInfo& aSnapInfo,
|
|
nsIScrollableFrame::ScrollUnit aUnit, const nsRect& aScrollRange,
|
|
const nsPoint& aStartPos, const nsPoint& aDestination);
|
|
};
|
|
|
|
} // namespace mozilla
|
|
|
|
#endif // mozilla_layout_ScrollSnap_h_
|