gecko-dev/layout/base/nsChangeHint.h
L. David Baron c7d4180816 Bug 996796 patch 7 - Add new restyle types that replace only the data from CSS transitions or animations. r=heycam
This is the start of a refactoring of the existing code in
CommonAnimationManager, nsTransitionManager, and nsAnimationManager,
which will be removed in later patches (after patches in between cause
this code to be used instead of the current code).

But it also handles interesting cases more correctly, such as cases
where style context parents are unusual.

FIXME: It would be nice to add tests for these cases, but they're mostly
pretty obscure (e.g., a transition of 'transform' that's affected by
inheriting 'transform' from ::first-line), so I'm not treating it as a
priority right now.
2014-08-02 19:37:43 -07:00

285 lines
11 KiB
C

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
/* constants for what needs to be recomputed in response to style changes */
#ifndef nsChangeHint_h___
#define nsChangeHint_h___
#include "nsDebug.h"
// Defines for various style related constants
enum nsChangeHint {
// change was visual only (e.g., COLOR=)
// Invalidates all descendant frames (including following
// placeholders to out-of-flow frames).
nsChangeHint_RepaintFrame = 0x01,
// For reflow, we want flags to give us arbitrary FrameNeedsReflow behavior.
// just do a FrameNeedsReflow.
nsChangeHint_NeedReflow = 0x02,
// Invalidate intrinsic widths on the frame's ancestors. Must not be set
// without setting nsChangeHint_NeedReflow.
nsChangeHint_ClearAncestorIntrinsics = 0x04,
// Invalidate intrinsic widths on the frame's descendants. Must not be set
// without also setting nsChangeHint_ClearAncestorIntrinsics.
nsChangeHint_ClearDescendantIntrinsics = 0x08,
// Force unconditional reflow of all descendants. Must not be set without
// setting nsChangeHint_NeedReflow, but is independent of both the
// Clear*Intrinsics flags.
nsChangeHint_NeedDirtyReflow = 0x10,
// change requires view to be updated, if there is one (e.g., clip:).
// Updates all descendants (including following placeholders to out-of-flows).
nsChangeHint_SyncFrameView = 0x20,
// The currently shown mouse cursor needs to be updated
nsChangeHint_UpdateCursor = 0x40,
/**
* Used when the computed value (a URI) of one or more of an element's
* filter/mask/clip/etc CSS properties changes, causing the element's frame
* to start/stop referencing (or reference different) SVG resource elements.
* (_Not_ used to handle changes to referenced resource elements.) Using this
* hint results in nsSVGEffects::UpdateEffects being called on the element's
* frame.
*/
nsChangeHint_UpdateEffects = 0x80,
/**
* Visual change only, but the change can be handled entirely by
* updating the layer(s) for the frame.
* Updates all descendants (including following placeholders to out-of-flows).
*/
nsChangeHint_UpdateOpacityLayer = 0x100,
/**
* Updates all descendants. Any placeholder descendants' out-of-flows
* are also descendants of the transformed frame, so they're updated.
*/
nsChangeHint_UpdateTransformLayer = 0x200,
/**
* Change requires frame change (e.g., display:).
* This subsumes all the above. Reconstructs all frame descendants,
* including following placeholders to out-of-flows.
*/
nsChangeHint_ReconstructFrame = 0x400,
/**
* The frame's overflow area has changed. Does not update any descendant
* frames.
*/
nsChangeHint_UpdateOverflow = 0x800,
/**
* The overflow area of the frame and all of its descendants has changed. This
* can happen through a text-decoration change.
*/
nsChangeHint_UpdateSubtreeOverflow = 0x1000,
/**
* The frame's overflow area has changed, through a change in its transform.
* Does not update any descendant frames.
*/
nsChangeHint_UpdatePostTransformOverflow = 0x2000,
/**
* The children-only transform of an SVG frame changed, requiring the
* overflow rects of the frame's immediate children to be updated.
*/
nsChangeHint_ChildrenOnlyTransform = 0x4000,
/**
* The frame's offsets have changed, while its dimensions might have
* changed as well. This hint is used for positioned frames if their
* offset changes. If we decide that the dimensions are likely to
* change, this will trigger a reflow.
*
* Note that this should probably be used in combination with
* nsChangeHint_UpdateOverflow in order to get the overflow areas of
* the ancestors updated as well.
*/
nsChangeHint_RecomputePosition = 0x8000,
/**
* Behaves like ReconstructFrame, but only if the frame has descendants
* that are absolutely or fixed position. Use this hint when a style change
* has changed whether the frame is a container for fixed-pos or abs-pos
* elements, but reframing is otherwise not needed.
*/
nsChangeHint_AddOrRemoveTransform = 0x10000,
/**
* This change hint has *no* change handling behavior. However, it
* exists to be a non-inherited hint, because when the border-style
* changes, and it's inherited by a child, that might require a reflow
* due to the border-width change on the child.
*/
nsChangeHint_BorderStyleNoneChange = 0x20000,
/**
* SVG textPath needs to be recomputed because the path has changed.
* This means that the glyph positions of the text need to be recomputed.
*/
nsChangeHint_UpdateTextPath = 0x40000,
/**
* This will schedule an invalidating paint. This is useful if something
* has changed which will be invalidated by DLBI.
*/
nsChangeHint_SchedulePaint = 0x80000
// IMPORTANT NOTE: When adding new hints, consider whether you need to
// add them to NS_HintsNotHandledForDescendantsIn() below.
};
// Redefine these operators to return nothing. This will catch any use
// of these operators on hints. We should not be using these operators
// on nsChangeHints
inline void operator<(nsChangeHint s1, nsChangeHint s2) {}
inline void operator>(nsChangeHint s1, nsChangeHint s2) {}
inline void operator!=(nsChangeHint s1, nsChangeHint s2) {}
inline void operator==(nsChangeHint s1, nsChangeHint s2) {}
inline void operator<=(nsChangeHint s1, nsChangeHint s2) {}
inline void operator>=(nsChangeHint s1, nsChangeHint s2) {}
// Operators on nsChangeHints
// Merge two hints, taking the union
inline nsChangeHint NS_CombineHint(nsChangeHint aH1, nsChangeHint aH2) {
return (nsChangeHint)(aH1 | aH2);
}
// Merge two hints, taking the union
inline nsChangeHint NS_SubtractHint(nsChangeHint aH1, nsChangeHint aH2) {
return (nsChangeHint)(aH1 & ~aH2);
}
// Merge the "src" hint into the "dst" hint
// Returns true iff the destination changed
inline bool NS_UpdateHint(nsChangeHint& aDest, nsChangeHint aSrc) {
nsChangeHint r = (nsChangeHint)(aDest | aSrc);
bool changed = (int)r != (int)aDest;
aDest = r;
return changed;
}
// Returns true iff the second hint contains all the hints of the first hint
inline bool NS_IsHintSubset(nsChangeHint aSubset, nsChangeHint aSuperSet) {
return (aSubset & aSuperSet) == aSubset;
}
/**
* We have an optimization when processing change hints which prevents
* us from visiting the descendants of a node when a hint on that node
* is being processed. This optimization does not apply in some of the
* cases where applying a hint to an element does not necessarily result
* in the same hint being handled on the descendants.
*/
// The most hints that NS_HintsNotHandledForDescendantsIn could possibly return:
#define nsChangeHint_Hints_NotHandledForDescendants nsChangeHint( \
nsChangeHint_UpdateTransformLayer | \
nsChangeHint_UpdateEffects | \
nsChangeHint_UpdateOpacityLayer | \
nsChangeHint_UpdateOverflow | \
nsChangeHint_UpdatePostTransformOverflow | \
nsChangeHint_ChildrenOnlyTransform | \
nsChangeHint_RecomputePosition | \
nsChangeHint_AddOrRemoveTransform | \
nsChangeHint_BorderStyleNoneChange | \
nsChangeHint_NeedReflow | \
nsChangeHint_ClearAncestorIntrinsics)
inline nsChangeHint NS_HintsNotHandledForDescendantsIn(nsChangeHint aChangeHint) {
nsChangeHint result = nsChangeHint(aChangeHint & (
nsChangeHint_UpdateTransformLayer |
nsChangeHint_UpdateEffects |
nsChangeHint_UpdateOpacityLayer |
nsChangeHint_UpdateOverflow |
nsChangeHint_UpdatePostTransformOverflow |
nsChangeHint_ChildrenOnlyTransform |
nsChangeHint_RecomputePosition |
nsChangeHint_AddOrRemoveTransform |
nsChangeHint_BorderStyleNoneChange));
if (!NS_IsHintSubset(nsChangeHint_NeedDirtyReflow, aChangeHint) &&
NS_IsHintSubset(nsChangeHint_NeedReflow, aChangeHint)) {
// If NeedDirtyReflow is *not* set, then NeedReflow is a
// non-inherited hint.
NS_UpdateHint(result, nsChangeHint_NeedReflow);
}
if (!NS_IsHintSubset(nsChangeHint_ClearDescendantIntrinsics, aChangeHint) &&
NS_IsHintSubset(nsChangeHint_ClearAncestorIntrinsics, aChangeHint)) {
// If ClearDescendantIntrinsics is *not* set, then
// ClearAncestorIntrinsics is a non-inherited hint.
NS_UpdateHint(result, nsChangeHint_ClearAncestorIntrinsics);
}
NS_ABORT_IF_FALSE(NS_IsHintSubset(result,
nsChangeHint_Hints_NotHandledForDescendants),
"something is inconsistent");
return result;
}
// Redefine the old NS_STYLE_HINT constants in terms of the new hint structure
#define NS_STYLE_HINT_NONE \
nsChangeHint(0)
#define NS_STYLE_HINT_VISUAL \
nsChangeHint(nsChangeHint_RepaintFrame | nsChangeHint_SyncFrameView | \
nsChangeHint_SchedulePaint)
#define nsChangeHint_AllReflowHints \
nsChangeHint(nsChangeHint_NeedReflow | \
nsChangeHint_ClearAncestorIntrinsics | \
nsChangeHint_ClearDescendantIntrinsics | \
nsChangeHint_NeedDirtyReflow)
#define NS_STYLE_HINT_REFLOW \
nsChangeHint(NS_STYLE_HINT_VISUAL | nsChangeHint_AllReflowHints)
#define NS_STYLE_HINT_FRAMECHANGE \
nsChangeHint(NS_STYLE_HINT_REFLOW | nsChangeHint_ReconstructFrame)
/**
* |nsRestyleHint| is a bitfield for the result of
* |HasStateDependentStyle| and |HasAttributeDependentStyle|. When no
* restyling is necessary, use |nsRestyleHint(0)|.
*/
enum nsRestyleHint {
// Rerun selector matching on the element. If a new style context
// results, update the style contexts of descendants. (Irrelevant if
// eRestyle_Subtree is also set, since that implies a superset of the
// work.)
eRestyle_Self = (1<<0),
// Rerun selector matching on the element and all of its descendants.
eRestyle_Subtree = (1<<1),
// Rerun selector matching on all later siblings of the element and
// all of their descendants.
eRestyle_LaterSiblings = (1<<2),
// Replace the style data coming from CSS transitions without updating
// any other style data. If a new style context results, update style
// contexts on the descendants. (Irrelevant if eRestyle_Self or
// eRestyle_Subtree is also set, since those imply a superset of the
// work.)
eRestyle_CSSTransitions = (1<<3),
// Replace the style data coming from CSS animations without updating
// any other style data. If a new style context results, update style
// contexts on the descendants. (Irrelevant if eRestyle_Self or
// eRestyle_Subtree is also set, since those imply a superset of the
// work.)
eRestyle_CSSAnimations = (1<<4),
};
#endif /* nsChangeHint_h___ */