Source code
Revision control
Copy as Markdown
Other Tools
/* 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
/* bit vectors for sets of CSS properties */
#ifndef nsCSSPropertyIDSet_h__
#define nsCSSPropertyIDSet_h__
#include <initializer_list>
#include <limits.h> // for CHAR_BIT
#include <ostream>
#include "mozilla/ArrayUtils.h"
// For COMPOSITOR_ANIMATABLE_PROPERTY_LIST and
// COMPOSITOR_ANIMATABLE_PROPERTY_LIST_LENGTH
#include "mozilla/AnimatedPropertyID.h"
#include "mozilla/CompositorAnimatableProperties.h"
#include "nsCSSProps.h" // For operator<< for nsCSSPropertyID
#include "nsCSSPropertyID.h"
/**
* nsCSSPropertyIDSet maintains a set of non-shorthand CSS properties. In
* other words, for each longhand CSS property we support, it has a bit
* for whether that property is in the set.
*/
class nsCSSPropertyIDSet {
public:
constexpr nsCSSPropertyIDSet() : mProperties{0} {}
// auto-generated copy-constructor OK
explicit constexpr nsCSSPropertyIDSet(
std::initializer_list<nsCSSPropertyID> aProperties)
: mProperties{0} {
for (auto property : aProperties) {
size_t p = property;
mProperties[p / kBitsInChunk] |= property_set_type(1)
<< (p % kBitsInChunk);
}
}
void AssertInSetRange(nsCSSPropertyID aProperty) const {
MOZ_DIAGNOSTIC_ASSERT(
0 <= aProperty && aProperty < eCSSProperty_COUNT_no_shorthands,
"out of bounds");
}
// Conversion of aProperty to |size_t| after AssertInSetRange
// lets the compiler generate significantly tighter code.
void AddProperty(nsCSSPropertyID aProperty) {
AssertInSetRange(aProperty);
size_t p = aProperty;
mProperties[p / kBitsInChunk] |= property_set_type(1) << (p % kBitsInChunk);
}
void RemoveProperty(nsCSSPropertyID aProperty) {
AssertInSetRange(aProperty);
size_t p = aProperty;
mProperties[p / kBitsInChunk] &=
~(property_set_type(1) << (p % kBitsInChunk));
}
bool HasProperty(const mozilla::AnimatedPropertyID& aProperty) const {
return !aProperty.IsCustom() && HasProperty(aProperty.mID);
}
bool HasProperty(nsCSSPropertyID aProperty) const {
AssertInSetRange(aProperty);
size_t p = aProperty;
return (mProperties[p / kBitsInChunk] &
(property_set_type(1) << (p % kBitsInChunk))) != 0;
}
// Returns an nsCSSPropertyIDSet including all properties that can be run
// on the compositor.
static constexpr nsCSSPropertyIDSet CompositorAnimatables() {
return nsCSSPropertyIDSet(COMPOSITOR_ANIMATABLE_PROPERTY_LIST);
}
static constexpr size_t CompositorAnimatableCount() {
return COMPOSITOR_ANIMATABLE_PROPERTY_LIST_LENGTH;
}
static constexpr size_t CompositorAnimatableDisplayItemCount() {
// We have 3 individual transforms and 5 motion path properties, and they
// also use DisplayItemType::TYPE_TRANSFORM.
return COMPOSITOR_ANIMATABLE_PROPERTY_LIST_LENGTH - 8;
}
static constexpr nsCSSPropertyIDSet CSSTransformProperties() {
return nsCSSPropertyIDSet{eCSSProperty_transform, eCSSProperty_translate,
eCSSProperty_rotate, eCSSProperty_scale};
}
static constexpr nsCSSPropertyIDSet MotionPathProperties() {
return nsCSSPropertyIDSet{
eCSSProperty_offset_path, eCSSProperty_offset_distance,
eCSSProperty_offset_rotate, eCSSProperty_offset_anchor,
eCSSProperty_offset_position};
}
static constexpr nsCSSPropertyIDSet TransformLikeProperties() {
return nsCSSPropertyIDSet{
eCSSProperty_transform, eCSSProperty_translate,
eCSSProperty_rotate, eCSSProperty_scale,
eCSSProperty_offset_path, eCSSProperty_offset_distance,
eCSSProperty_offset_rotate, eCSSProperty_offset_anchor,
eCSSProperty_offset_position};
}
static constexpr nsCSSPropertyIDSet OpacityProperties() {
return nsCSSPropertyIDSet{eCSSProperty_opacity};
}
bool Intersects(const nsCSSPropertyIDSet& aOther) const {
for (size_t i = 0; i < std::size(mProperties); ++i) {
if (mProperties[i] & aOther.mProperties[i]) {
return true;
}
}
return false;
}
void Empty() { memset(mProperties, 0, sizeof(mProperties)); }
void AssertIsEmpty(const char* aText) const {
for (size_t i = 0; i < std::size(mProperties); ++i) {
NS_ASSERTION(mProperties[i] == 0, aText);
}
}
bool Equals(const nsCSSPropertyIDSet& aOther) const {
return mozilla::ArrayEqual(mProperties, aOther.mProperties);
}
bool IsEmpty() const {
for (size_t i = 0; i < std::size(mProperties); ++i) {
if (mProperties[i] != 0) {
return false;
}
}
return true;
}
bool IsSubsetOf(const nsCSSPropertyIDSet& aOther) const {
return this->Intersect(aOther).Equals(*this);
}
// Returns a new nsCSSPropertyIDSet with all properties that are both in
// this set and |aOther|.
nsCSSPropertyIDSet Intersect(const nsCSSPropertyIDSet& aOther) const {
nsCSSPropertyIDSet result;
for (size_t i = 0; i < std::size(mProperties); ++i) {
result.mProperties[i] = mProperties[i] & aOther.mProperties[i];
}
return result;
}
// Returns a new nsCSSPropertyIDSet with all properties that are in either
// this set or |aOther| but not both.
nsCSSPropertyIDSet Xor(const nsCSSPropertyIDSet& aOther) const {
nsCSSPropertyIDSet result;
for (size_t i = 0; i < std::size(mProperties); ++i) {
result.mProperties[i] = mProperties[i] ^ aOther.mProperties[i];
}
return result;
}
nsCSSPropertyIDSet& operator|=(const nsCSSPropertyIDSet& aOther) {
for (size_t i = 0; i < std::size(mProperties); ++i) {
mProperties[i] |= aOther.mProperties[i];
}
return *this;
}
private:
typedef unsigned long property_set_type;
public:
// number of bits in |property_set_type|.
static const size_t kBitsInChunk = sizeof(property_set_type) * CHAR_BIT;
// number of |property_set_type|s in the set
static const size_t kChunkCount =
(eCSSProperty_COUNT_no_shorthands + kBitsInChunk - 1) / kBitsInChunk;
/*
* For fast enumeration of all the bits that are set, callers can
* check each chunk against zero (since in normal cases few bits are
* likely to be set).
*/
bool HasPropertyInChunk(size_t aChunk) const {
return mProperties[aChunk] != 0;
}
bool HasPropertyAt(size_t aChunk, size_t aBit) const {
return (mProperties[aChunk] & (property_set_type(1) << aBit)) != 0;
}
static nsCSSPropertyID CSSPropertyAt(size_t aChunk, size_t aBit) {
return nsCSSPropertyID(aChunk * kBitsInChunk + aBit);
}
// Iterator for use in range-based for loops
class Iterator {
public:
Iterator(Iterator&& aOther)
: mPropertySet(aOther.mPropertySet),
mChunk(aOther.mChunk),
mBit(aOther.mBit) {}
static Iterator BeginIterator(const nsCSSPropertyIDSet& aPropertySet) {
Iterator result(aPropertySet);
// Search for the first property.
// Unsigned integer overflow is defined so the following is safe.
result.mBit = -1;
++result;
return result;
}
static Iterator EndIterator(const nsCSSPropertyIDSet& aPropertySet) {
Iterator result(aPropertySet);
result.mChunk = kChunkCount;
result.mBit = 0;
return result;
}
bool operator!=(const Iterator& aOther) const {
return mChunk != aOther.mChunk || mBit != aOther.mBit;
}
Iterator& operator++() {
MOZ_ASSERT(mChunk < kChunkCount, "Should not iterate beyond end");
do {
mBit++;
} while (mBit < kBitsInChunk &&
!mPropertySet.HasPropertyAt(mChunk, mBit));
if (mBit != kBitsInChunk) {
return *this;
}
do {
mChunk++;
} while (mChunk < kChunkCount &&
!mPropertySet.HasPropertyInChunk(mChunk));
mBit = 0;
if (mChunk != kChunkCount) {
while (mBit < kBitsInChunk &&
!mPropertySet.HasPropertyAt(mChunk, mBit)) {
mBit++;
}
}
return *this;
}
nsCSSPropertyID operator*() {
MOZ_ASSERT(mChunk < kChunkCount, "Should not dereference beyond end");
return nsCSSPropertyIDSet::CSSPropertyAt(mChunk, mBit);
}
private:
explicit Iterator(const nsCSSPropertyIDSet& aPropertySet)
: mPropertySet(aPropertySet) {}
Iterator() = delete;
Iterator(const Iterator&) = delete;
Iterator& operator=(const Iterator&) = delete;
Iterator& operator=(const Iterator&&) = delete;
const nsCSSPropertyIDSet& mPropertySet;
size_t mChunk = 0;
size_t mBit = 0;
};
Iterator begin() const { return Iterator::BeginIterator(*this); }
Iterator end() const { return Iterator::EndIterator(*this); }
private:
property_set_type mProperties[kChunkCount];
};
// MOZ_DBG support
inline std::ostream& operator<<(std::ostream& aOut,
const nsCSSPropertyIDSet& aPropertySet) {
AutoTArray<nsCSSPropertyID, 16> properties;
for (nsCSSPropertyID property : aPropertySet) {
properties.AppendElement(property);
}
return aOut << properties;
}
#endif /* !defined(nsCSSPropertyIDSet_h__) */