gecko-dev/layout/style/nsCSSValue.h

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/* -*- 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/. */
/* representation of simple property values within CSS declarations */
#ifndef nsCSSValue_h___
#define nsCSSValue_h___
#include "mozilla/Attributes.h"
#include "mozilla/CORSMode.h"
#include "mozilla/EnumTypeTraits.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/ServoBindingTypes.h"
#include "mozilla/URLExtraData.h"
#include "mozilla/UniquePtr.h"
#include "nsCoord.h"
#include "nsTArray.h"
#include <type_traits>
// XXX Avoid including this here by moving function bodies to the cpp file
#include "mozilla/FloatingPoint.h"
class imgRequestProxy;
class nsAtom;
class nsIContent;
class nsIPrincipal;
class nsIURI;
class nsPresContext;
template <class T>
class nsPtrHashKey;
struct RawServoCssUrlData;
namespace mozilla {
class CSSStyleSheet;
} // namespace mozilla
// Forward declaration copied here since ServoBindings.h #includes nsCSSValue.h.
extern "C" {
mozilla::URLExtraData* Servo_CssUrlData_GetExtraData(const RawServoCssUrlData*);
bool Servo_CssUrlData_IsLocalRef(const RawServoCssUrlData* url);
}
enum nsCSSUnit : uint32_t {
eCSSUnit_Null = 0, // (n/a) null unit, value is not specified
eCSSUnit_Percent = 100, // (1.0 == 100%) value is percentage of
// something
eCSSUnit_Number = 101, // value is numeric (usually multiplier,
// different behavior than percent)
// Font relative measure
eCSSUnit_EM = 800, // == current font size
eCSSUnit_XHeight = 801, // distance from top of lower case x to
// baseline
eCSSUnit_Char = 802, // number of characters, used for width with
// monospace font
eCSSUnit_RootEM = 803, // == root element font size
eCSSUnit_Ideographic = 804, // == CJK water ideograph width
eCSSUnit_CapHeight = 805, // == Capital letter height
// Screen relative measure
eCSSUnit_Point = 900, // 4/3 of a CSS pixel
eCSSUnit_Inch = 901, // 96 CSS pixels
eCSSUnit_Millimeter = 902, // 96/25.4 CSS pixels
eCSSUnit_Centimeter = 903, // 96/2.54 CSS pixels
eCSSUnit_Pica = 904, // 12 points == 16 CSS pixls
eCSSUnit_Quarter = 905, // 96/101.6 CSS pixels
eCSSUnit_Pixel = 906, // CSS pixel unit
// Viewport percentage lengths
eCSSUnit_VW = 950,
eCSSUnit_VH = 951,
eCSSUnit_VMin = 952,
eCSSUnit_VMax = 953,
};
struct nsCSSValuePair;
struct nsCSSValuePair_heap;
struct nsCSSValueList;
struct nsCSSValueList_heap;
struct nsCSSValueSharedList;
struct nsCSSValuePairList;
struct nsCSSValuePairList_heap;
class nsCSSValue {
public:
explicit nsCSSValue() : mUnit(eCSSUnit_Null) {}
nsCSSValue(float aValue, nsCSSUnit aUnit);
nsCSSValue(const nsCSSValue& aCopy);
nsCSSValue(nsCSSValue&& aOther) : mUnit(aOther.mUnit), mValue(aOther.mValue) {
aOther.mUnit = eCSSUnit_Null;
}
nsCSSValue& operator=(const nsCSSValue& aCopy);
nsCSSValue& operator=(nsCSSValue&& aCopy);
bool operator==(const nsCSSValue& aOther) const;
bool operator!=(const nsCSSValue& aOther) const { return !(*this == aOther); }
nsCSSUnit GetUnit() const { return mUnit; }
bool IsLengthUnit() const {
return eCSSUnit_EM <= mUnit && mUnit <= eCSSUnit_Pixel;
}
/**
* A "pixel" length unit is a some multiple of CSS pixels.
*/
static bool IsPixelLengthUnit(nsCSSUnit aUnit) {
return eCSSUnit_Point <= aUnit && aUnit <= eCSSUnit_Pixel;
}
bool IsPixelLengthUnit() const { return IsPixelLengthUnit(mUnit); }
static bool IsPercentLengthUnit(nsCSSUnit aUnit) {
return aUnit == eCSSUnit_Percent;
}
static bool IsFloatUnit(nsCSSUnit aUnit) { return eCSSUnit_Number <= aUnit; }
float GetPercentValue() const {
MOZ_ASSERT(mUnit == eCSSUnit_Percent, "not a percent value");
return mValue;
}
float GetFloatValue() const {
MOZ_ASSERT(eCSSUnit_Number <= mUnit, "not a float value");
MOZ_ASSERT(!std::isnan(mValue));
return mValue;
}
nscoord GetPixelLength() const;
void Reset() { mUnit = eCSSUnit_Null; }
~nsCSSValue() { Reset(); }
public:
void SetPercentValue(float aValue);
void SetFloatValue(float aValue, nsCSSUnit aUnit);
protected:
nsCSSUnit mUnit;
float mValue;
};
#endif /* nsCSSValue_h___ */