gecko-dev/layout/style/nsStyleCoord.h
2012-05-21 12:12:37 +01:00

430 lines
12 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/. */
/* representation of length values in computed style data */
#ifndef nsStyleCoord_h___
#define nsStyleCoord_h___
#include "nscore.h"
#include "nsCoord.h"
#include "nsCRT.h"
#include "nsStyleConsts.h"
class nsString;
class nsStyleContext;
enum nsStyleUnit {
eStyleUnit_Null = 0, // (no value) value is not specified
eStyleUnit_Normal = 1, // (no value)
eStyleUnit_Auto = 2, // (no value)
eStyleUnit_None = 3, // (no value)
eStyleUnit_Percent = 10, // (float) 1.0 == 100%
eStyleUnit_Factor = 11, // (float) a multiplier
eStyleUnit_Degree = 12, // (float) angle in degrees
eStyleUnit_Grad = 13, // (float) angle in grads
eStyleUnit_Radian = 14, // (float) angle in radians
eStyleUnit_Turn = 15, // (float) angle in turns
eStyleUnit_Coord = 20, // (nscoord) value is twips
eStyleUnit_Integer = 30, // (int) value is simple integer
eStyleUnit_Enumerated = 32, // (int) value has enumerated meaning
// The following are allocated types. They are weak pointers to
// values allocated by nsStyleContext::Alloc.
eStyleUnit_Calc = 40 // (Calc*) calc() toplevel; always present
// to distinguish 50% from calc(50%), etc.
};
typedef union {
PRInt32 mInt; // nscoord is a PRInt32 for now
float mFloat;
// An mPointer is a weak pointer to a value that is guaranteed to
// outlive the nsStyleCoord. In the case of nsStyleCoord::Calc*, it
// is a pointer owned by the style context, allocated through
// nsStyleContext::Alloc (and, therefore, is never stored in the rule
// tree).
void* mPointer;
} nsStyleUnion;
/**
* Class that hold a single size specification used by the style
* system. The size specification consists of two parts -- a number
* and a unit. The number is an integer, a floating point value, an
* nscoord, or undefined, and the unit is an nsStyleUnit. Checking
* the unit is a must before asking for the value in any particular
* form.
*/
class nsStyleCoord {
public:
struct Calc {
// Every calc() expression evaluates to a length plus a percentage.
nscoord mLength;
float mPercent;
bool mHasPercent; // whether there was any % syntax, even if 0
bool operator==(const Calc& aOther) const {
return mLength == aOther.mLength &&
mPercent == aOther.mPercent &&
mHasPercent == aOther.mHasPercent;
}
bool operator!=(const Calc& aOther) const { return !(*this == aOther); }
};
nsStyleCoord(nsStyleUnit aUnit = eStyleUnit_Null);
enum CoordConstructorType { CoordConstructor };
inline nsStyleCoord(nscoord aValue, CoordConstructorType);
nsStyleCoord(PRInt32 aValue, nsStyleUnit aUnit);
nsStyleCoord(float aValue, nsStyleUnit aUnit);
inline nsStyleCoord(const nsStyleCoord& aCopy);
inline nsStyleCoord(const nsStyleUnion& aValue, nsStyleUnit aUnit);
nsStyleCoord& operator=(const nsStyleCoord& aOther)
{
mUnit = aOther.mUnit;
mValue = aOther.mValue;
return *this;
}
bool operator==(const nsStyleCoord& aOther) const;
bool operator!=(const nsStyleCoord& aOther) const;
nsStyleUnit GetUnit() const {
NS_ASSERTION(mUnit != eStyleUnit_Null, "reading uninitialized value");
return mUnit;
}
bool IsAngleValue() const {
return eStyleUnit_Degree <= mUnit && mUnit <= eStyleUnit_Turn;
}
bool IsCalcUnit() const {
return eStyleUnit_Calc == mUnit;
}
bool IsPointerValue() const {
return IsCalcUnit();
}
bool IsCoordPercentCalcUnit() const {
return mUnit == eStyleUnit_Coord ||
mUnit == eStyleUnit_Percent ||
IsCalcUnit();
}
// Does this calc() expression have any percentages inside it? Can be
// called only when IsCalcUnit() is true.
bool CalcHasPercent() const {
return GetCalcValue()->mHasPercent;
}
bool HasPercent() const {
return mUnit == eStyleUnit_Percent ||
(IsCalcUnit() && CalcHasPercent());
}
bool ConvertsToLength() const {
return mUnit == eStyleUnit_Coord ||
(IsCalcUnit() && !CalcHasPercent());
}
nscoord GetCoordValue() const;
PRInt32 GetIntValue() const;
float GetPercentValue() const;
float GetFactorValue() const;
float GetAngleValue() const;
double GetAngleValueInRadians() const;
Calc* GetCalcValue() const;
void GetUnionValue(nsStyleUnion& aValue) const;
void Reset(); // sets to null
void SetCoordValue(nscoord aValue);
void SetIntValue(PRInt32 aValue, nsStyleUnit aUnit);
void SetPercentValue(float aValue);
void SetFactorValue(float aValue);
void SetAngleValue(float aValue, nsStyleUnit aUnit);
void SetNormalValue();
void SetAutoValue();
void SetNoneValue();
void SetCalcValue(Calc* aValue);
private:
nsStyleUnit mUnit;
nsStyleUnion mValue;
};
/**
* Class that represents a set of top/right/bottom/left nsStyleCoords.
* This is commonly used to hold the widths of the borders, margins,
* or paddings of a box.
*/
class nsStyleSides {
public:
nsStyleSides();
// nsStyleSides& operator=(const nsStyleSides& aCopy); // use compiler's version
bool operator==(const nsStyleSides& aOther) const;
bool operator!=(const nsStyleSides& aOther) const;
inline nsStyleUnit GetUnit(mozilla::css::Side aSide) const;
inline nsStyleUnit GetLeftUnit() const;
inline nsStyleUnit GetTopUnit() const;
inline nsStyleUnit GetRightUnit() const;
inline nsStyleUnit GetBottomUnit() const;
inline nsStyleCoord Get(mozilla::css::Side aSide) const;
inline nsStyleCoord GetLeft() const;
inline nsStyleCoord GetTop() const;
inline nsStyleCoord GetRight() const;
inline nsStyleCoord GetBottom() const;
void Reset();
inline void Set(mozilla::css::Side aSide, const nsStyleCoord& aCoord);
inline void SetLeft(const nsStyleCoord& aCoord);
inline void SetTop(const nsStyleCoord& aCoord);
inline void SetRight(const nsStyleCoord& aCoord);
inline void SetBottom(const nsStyleCoord& aCoord);
protected:
PRUint8 mUnits[4];
nsStyleUnion mValues[4];
};
/**
* Class that represents a set of top-left/top-right/bottom-left/bottom-right
* nsStyleCoord pairs. This is used to hold the dimensions of the
* corners of a box (for, e.g., border-radius and outline-radius).
*/
class nsStyleCorners {
public:
nsStyleCorners();
// use compiler's version
//nsStyleCorners& operator=(const nsStyleCorners& aCopy);
bool operator==(const nsStyleCorners& aOther) const;
bool operator!=(const nsStyleCorners& aOther) const;
// aCorner is always one of NS_CORNER_* defined in nsStyleConsts.h
inline nsStyleUnit GetUnit(PRUint8 aHalfCorner) const;
inline nsStyleCoord Get(PRUint8 aHalfCorner) const;
void Reset();
inline void Set(PRUint8 aHalfCorner, const nsStyleCoord& aCoord);
protected:
PRUint8 mUnits[8];
nsStyleUnion mValues[8];
};
// -------------------------
// nsStyleCoord inlines
//
inline nsStyleCoord::nsStyleCoord(nscoord aValue, CoordConstructorType)
: mUnit(eStyleUnit_Coord)
{
mValue.mInt = aValue;
}
// FIXME: In C++0x we can rely on the default copy constructor since
// default copy construction is defined properly for unions. But when
// can we actually use that? (It seems to work in gcc 4.4.)
inline nsStyleCoord::nsStyleCoord(const nsStyleCoord& aCopy)
: mUnit(aCopy.mUnit)
{
if ((eStyleUnit_Percent <= mUnit) && (mUnit < eStyleUnit_Coord)) {
mValue.mFloat = aCopy.mValue.mFloat;
}
else if (IsPointerValue()) {
mValue.mPointer = aCopy.mValue.mPointer;
}
else {
mValue.mInt = aCopy.mValue.mInt;
}
}
inline nsStyleCoord::nsStyleCoord(const nsStyleUnion& aValue, nsStyleUnit aUnit)
: mUnit(aUnit), mValue(aValue)
{
}
inline bool nsStyleCoord::operator!=(const nsStyleCoord& aOther) const
{
return !((*this) == aOther);
}
inline nscoord nsStyleCoord::GetCoordValue() const
{
NS_ASSERTION((mUnit == eStyleUnit_Coord), "not a coord value");
if (mUnit == eStyleUnit_Coord) {
return mValue.mInt;
}
return 0;
}
inline PRInt32 nsStyleCoord::GetIntValue() const
{
NS_ASSERTION((mUnit == eStyleUnit_Enumerated) ||
(mUnit == eStyleUnit_Integer), "not an int value");
if ((mUnit == eStyleUnit_Enumerated) ||
(mUnit == eStyleUnit_Integer)) {
return mValue.mInt;
}
return 0;
}
inline float nsStyleCoord::GetPercentValue() const
{
NS_ASSERTION(mUnit == eStyleUnit_Percent, "not a percent value");
if (mUnit == eStyleUnit_Percent) {
return mValue.mFloat;
}
return 0.0f;
}
inline float nsStyleCoord::GetFactorValue() const
{
NS_ASSERTION(mUnit == eStyleUnit_Factor, "not a factor value");
if (mUnit == eStyleUnit_Factor) {
return mValue.mFloat;
}
return 0.0f;
}
inline float nsStyleCoord::GetAngleValue() const
{
NS_ASSERTION(mUnit >= eStyleUnit_Degree &&
mUnit <= eStyleUnit_Turn, "not an angle value");
if (mUnit >= eStyleUnit_Degree && mUnit <= eStyleUnit_Turn) {
return mValue.mFloat;
}
return 0.0f;
}
inline nsStyleCoord::Calc* nsStyleCoord::GetCalcValue() const
{
NS_ASSERTION(IsCalcUnit(), "not a pointer value");
if (IsCalcUnit()) {
return static_cast<Calc*>(mValue.mPointer);
}
return nsnull;
}
inline void nsStyleCoord::GetUnionValue(nsStyleUnion& aValue) const
{
aValue = mValue;
}
// -------------------------
// nsStyleSides inlines
//
inline bool nsStyleSides::operator!=(const nsStyleSides& aOther) const
{
return !((*this) == aOther);
}
inline nsStyleUnit nsStyleSides::GetUnit(mozilla::css::Side aSide) const
{
return (nsStyleUnit)mUnits[aSide];
}
inline nsStyleUnit nsStyleSides::GetLeftUnit() const
{
return GetUnit(NS_SIDE_LEFT);
}
inline nsStyleUnit nsStyleSides::GetTopUnit() const
{
return GetUnit(NS_SIDE_TOP);
}
inline nsStyleUnit nsStyleSides::GetRightUnit() const
{
return GetUnit(NS_SIDE_RIGHT);
}
inline nsStyleUnit nsStyleSides::GetBottomUnit() const
{
return GetUnit(NS_SIDE_BOTTOM);
}
inline nsStyleCoord nsStyleSides::Get(mozilla::css::Side aSide) const
{
return nsStyleCoord(mValues[aSide], nsStyleUnit(mUnits[aSide]));
}
inline nsStyleCoord nsStyleSides::GetLeft() const
{
return Get(NS_SIDE_LEFT);
}
inline nsStyleCoord nsStyleSides::GetTop() const
{
return Get(NS_SIDE_TOP);
}
inline nsStyleCoord nsStyleSides::GetRight() const
{
return Get(NS_SIDE_RIGHT);
}
inline nsStyleCoord nsStyleSides::GetBottom() const
{
return Get(NS_SIDE_BOTTOM);
}
inline void nsStyleSides::Set(mozilla::css::Side aSide, const nsStyleCoord& aCoord)
{
mUnits[aSide] = aCoord.GetUnit();
aCoord.GetUnionValue(mValues[aSide]);
}
inline void nsStyleSides::SetLeft(const nsStyleCoord& aCoord)
{
Set(NS_SIDE_LEFT, aCoord);
}
inline void nsStyleSides::SetTop(const nsStyleCoord& aCoord)
{
Set(NS_SIDE_TOP, aCoord);
}
inline void nsStyleSides::SetRight(const nsStyleCoord& aCoord)
{
Set(NS_SIDE_RIGHT, aCoord);
}
inline void nsStyleSides::SetBottom(const nsStyleCoord& aCoord)
{
Set(NS_SIDE_BOTTOM, aCoord);
}
// -------------------------
// nsStyleCorners inlines
//
inline bool nsStyleCorners::operator!=(const nsStyleCorners& aOther) const
{
return !((*this) == aOther);
}
inline nsStyleUnit nsStyleCorners::GetUnit(PRUint8 aCorner) const
{
return (nsStyleUnit)mUnits[aCorner];
}
inline nsStyleCoord nsStyleCorners::Get(PRUint8 aCorner) const
{
return nsStyleCoord(mValues[aCorner], nsStyleUnit(mUnits[aCorner]));
}
inline void nsStyleCorners::Set(PRUint8 aCorner, const nsStyleCoord& aCoord)
{
mUnits[aCorner] = aCoord.GetUnit();
aCoord.GetUnionValue(mValues[aCorner]);
}
#endif /* nsStyleCoord_h___ */