gecko-dev/layout/style/LayerAnimationInfo.h
2018-11-13 10:22:24 +00:00

86 lines
3.1 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_LayerAnimationInfo_h
#define mozilla_LayerAnimationInfo_h
#include "nsChangeHint.h"
#include "nsCSSPropertyID.h"
#include "nsCSSPropertyIDSet.h"
#include "nsDisplayList.h" // For nsDisplayItem::Type
#include "mozilla/Array.h"
namespace mozilla {
struct LayerAnimationInfo {
// Returns the corresponding display item type for |aProperty| when it is
// animated on the compositor.
// Returns DisplayItemType::TYPE_ZERO if |aProperty| cannot be animated on the
// compositor.
static DisplayItemType
GetDisplayItemTypeForProperty(nsCSSPropertyID aProperty);
// Returns the corresponding CSS properties for |aDisplayItemType|.
//
// This function works only for display items tied to CSS properties that can
// be animated on the compositor.
static inline const nsCSSPropertyIDSet&
GetCSSPropertiesFor(DisplayItemType aDisplayItemType)
{
static const nsCSSPropertyIDSet transformProperties =
nsCSSPropertyIDSet{ eCSSProperty_transform };
static const nsCSSPropertyIDSet opacityProperties =
nsCSSPropertyIDSet{ eCSSProperty_opacity };
static const nsCSSPropertyIDSet empty = nsCSSPropertyIDSet();
switch (aDisplayItemType) {
case DisplayItemType::TYPE_OPACITY:
return opacityProperties;
case DisplayItemType::TYPE_TRANSFORM:
return transformProperties;
default:
MOZ_ASSERT_UNREACHABLE("Should not be called for display item types "
"that are not able to have animations on the "
"compositor");
return empty;
}
}
// Returns the appropriate change hint for updating the display item for
// |aDisplayItemType|.
//
// This function works only for display items tied to CSS properties that can
// be animated on the compositor.
static inline nsChangeHint
GetChangeHintFor(DisplayItemType aDisplayItemType)
{
switch (aDisplayItemType) {
case DisplayItemType::TYPE_OPACITY:
return nsChangeHint_UpdateOpacityLayer;
case DisplayItemType::TYPE_TRANSFORM:
return nsChangeHint_UpdateTransformLayer;
default:
MOZ_ASSERT_UNREACHABLE("Should not be called for display item types "
"that are not able to have animations on the "
"compositor");
return nsChangeHint(0);
}
}
// An array of DisplayItemType corresponding to the display item taht we can
// animate on the compositor.
//
// This is used to look up the appropriate change hint in cases when
// animations need updating but no other change hint is generated.
static const Array<DisplayItemType,
nsCSSPropertyIDSet::CompositorAnimatableCount()>
sDisplayItemTypes;
};
} // namespace mozilla
#endif /* !defined(mozilla_LayerAnimationInfo_h) */