gecko-dev/layout/style/nsStyleCoord.cpp

/* -*- 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 length values in computed style data */

#include "mozilla/HashFunctions.h"
#include "mozilla/PodOperations.h"

// nsStyleCoord.h must not be the first header in a unified source file,
// otherwise it may not build with MSVC due to a bug in our STL wrapper.
// See bug 1331102.
#include "nsStyleCoord.h"

using namespace mozilla;

nsStyleCoord::nsStyleCoord(nsStyleUnit aUnit) : mUnit(aUnit) {
  NS_ASSERTION(aUnit < eStyleUnit_Percent, "not a valueless unit");
  if (aUnit >= eStyleUnit_Percent) {
    mUnit = eStyleUnit_Null;
  }
  mValue.mInt = 0;
}

nsStyleCoord::nsStyleCoord(int32_t aValue, nsStyleUnit aUnit) : mUnit(aUnit) {
  // if you want to pass in eStyleUnit_Coord, don't. instead, use the
  // constructor just above this one... MMP
  NS_ASSERTION(
      (aUnit == eStyleUnit_Enumerated) || (aUnit == eStyleUnit_Integer),
      "not an int value");
  if ((aUnit == eStyleUnit_Enumerated) || (aUnit == eStyleUnit_Integer)) {
    mValue.mInt = aValue;
  } else {
    mUnit = eStyleUnit_Null;
    mValue.mInt = 0;
  }
}

nsStyleCoord::nsStyleCoord(float aValue, nsStyleUnit aUnit) : mUnit(aUnit) {
  if (aUnit < eStyleUnit_Percent || aUnit >= eStyleUnit_Coord) {
    MOZ_ASSERT_UNREACHABLE("not a float value");
    mUnit = eStyleUnit_Null;
    mValue.mInt = 0;
  } else {
    mValue.mFloat = aValue;
  }
}

bool nsStyleCoord::operator==(const nsStyleCoord& aOther) const {
  if (mUnit != aOther.mUnit) {
    return false;
  }
  switch (mUnit) {
    case eStyleUnit_Null:
    case eStyleUnit_Normal:
    case eStyleUnit_Auto:
    case eStyleUnit_None:
      return true;
    case eStyleUnit_Percent:
    case eStyleUnit_Factor:
    case eStyleUnit_Degree:
    case eStyleUnit_FlexFraction:
      return mValue.mFloat == aOther.mValue.mFloat;
    case eStyleUnit_Coord:
    case eStyleUnit_Integer:
    case eStyleUnit_Enumerated:
      return mValue.mInt == aOther.mValue.mInt;
    case eStyleUnit_Calc:
      return *this->GetCalcValue() == *aOther.GetCalcValue();
  }
  MOZ_ASSERT(false, "unexpected unit");
  return false;
}

void nsStyleCoord::Reset() { Reset(mUnit, mValue); }

void nsStyleCoord::SetCoordValue(nscoord aValue) {
  Reset();
  mUnit = eStyleUnit_Coord;
  mValue.mInt = aValue;
}

void nsStyleCoord::SetIntValue(int32_t aValue, nsStyleUnit aUnit) {
  NS_ASSERTION(
      (aUnit == eStyleUnit_Enumerated) || (aUnit == eStyleUnit_Integer),
      "not an int value");
  Reset();
  if ((aUnit == eStyleUnit_Enumerated) || (aUnit == eStyleUnit_Integer)) {
    mUnit = aUnit;
    mValue.mInt = aValue;
  }
}

void nsStyleCoord::SetPercentValue(float aValue) {
  Reset();
  mUnit = eStyleUnit_Percent;
  mValue.mFloat = aValue;
}

void nsStyleCoord::SetFactorValue(float aValue) {
  Reset();
  mUnit = eStyleUnit_Factor;
  mValue.mFloat = aValue;
}

void nsStyleCoord::SetFlexFractionValue(float aValue) {
  Reset();
  mUnit = eStyleUnit_FlexFraction;
  mValue.mFloat = aValue;
}

void nsStyleCoord::SetCalcValue(Calc* aValue) {
  Reset();
  mUnit = eStyleUnit_Calc;
  mValue.mPointer = aValue;
  aValue->AddRef();
}

void nsStyleCoord::SetNormalValue() {
  Reset();
  mUnit = eStyleUnit_Normal;
  mValue.mInt = 0;
}

void nsStyleCoord::SetAutoValue() {
  Reset();
  mUnit = eStyleUnit_Auto;
  mValue.mInt = 0;
}

void nsStyleCoord::SetNoneValue() {
  Reset();
  mUnit = eStyleUnit_None;
  mValue.mInt = 0;
}

// accessors that are not inlined

double nsStyleCoord::GetAngleValueInDegrees() const {
  // Note that this extends the value from float to double.
  return GetAngleValue();
}

double nsStyleCoord::GetAngleValueInRadians() const {
  return GetAngleValueInDegrees() * M_PI / 180.0;
}

nscoord nsStyleCoord::ComputeComputedCalc(nscoord aPercentageBasis) const {
  Calc* calc = GetCalcValue();
  return calc->mLength +
         NSToCoordFloorClamped(aPercentageBasis * calc->mPercent);
}

nscoord nsStyleCoord::ComputeCoordPercentCalc(nscoord aPercentageBasis) const {
  switch (GetUnit()) {
    case eStyleUnit_Coord:
      return GetCoordValue();
    case eStyleUnit_Percent:
      return NSToCoordFloorClamped(aPercentageBasis * GetPercentValue());
    case eStyleUnit_Calc:
      return ComputeComputedCalc(aPercentageBasis);
    default:
      MOZ_ASSERT_UNREACHABLE("Unexpected unit!");
      return 0;
  }
}

nsStyleSides::nsStyleSides() {
  NS_FOR_CSS_SIDES(i) { mUnits[i] = eStyleUnit_Null; }
  mozilla::PodArrayZero(mValues);
}

nsStyleSides::nsStyleSides(const nsStyleSides& aOther) {
  NS_FOR_CSS_SIDES(i) { mUnits[i] = eStyleUnit_Null; }
  *this = aOther;
}

nsStyleSides::~nsStyleSides() { Reset(); }

nsStyleSides& nsStyleSides::operator=(const nsStyleSides& aCopy) {
  if (this != &aCopy) {
    NS_FOR_CSS_SIDES(i) {
      nsStyleCoord::SetValue(mUnits[i], mValues[i], aCopy.mUnits[i],
                             aCopy.mValues[i]);
    }
  }
  return *this;
}

bool nsStyleSides::operator==(const nsStyleSides& aOther) const {
  NS_FOR_CSS_SIDES(i) {
    if (nsStyleCoord(mValues[i], (nsStyleUnit)mUnits[i]) !=
        nsStyleCoord(aOther.mValues[i], (nsStyleUnit)aOther.mUnits[i])) {
      return false;
    }
  }
  return true;
}

void nsStyleSides::Reset() {
  NS_FOR_CSS_SIDES(i) { nsStyleCoord::Reset(mUnits[i], mValues[i]); }
}

// Validation of SideIsVertical.
#define CASE(side, result) \
  static_assert(SideIsVertical(side) == result, "SideIsVertical is wrong")
CASE(eSideTop, false);
CASE(eSideRight, true);
CASE(eSideBottom, false);
CASE(eSideLeft, true);
#undef CASE

// Validation of HalfCornerIsX.
#define CASE(corner, result) \
  static_assert(HalfCornerIsX(corner) == result, "HalfCornerIsX is wrong")
CASE(eCornerTopLeftX, true);
CASE(eCornerTopLeftY, false);
CASE(eCornerTopRightX, true);
CASE(eCornerTopRightY, false);
CASE(eCornerBottomRightX, true);
CASE(eCornerBottomRightY, false);
CASE(eCornerBottomLeftX, true);
CASE(eCornerBottomLeftY, false);
#undef CASE

// Validation of HalfToFullCorner.
#define CASE(corner, result)                        \
  static_assert(HalfToFullCorner(corner) == result, \
                "HalfToFullCorner is "              \
                "wrong")
CASE(eCornerTopLeftX, eCornerTopLeft);
CASE(eCornerTopLeftY, eCornerTopLeft);
CASE(eCornerTopRightX, eCornerTopRight);
CASE(eCornerTopRightY, eCornerTopRight);
CASE(eCornerBottomRightX, eCornerBottomRight);
CASE(eCornerBottomRightY, eCornerBottomRight);
CASE(eCornerBottomLeftX, eCornerBottomLeft);
CASE(eCornerBottomLeftY, eCornerBottomLeft);
#undef CASE

// Validation of FullToHalfCorner.
#define CASE(corner, vert, result)                        \
  static_assert(FullToHalfCorner(corner, vert) == result, \
                "FullToHalfCorner is wrong")
CASE(eCornerTopLeft, false, eCornerTopLeftX);
CASE(eCornerTopLeft, true, eCornerTopLeftY);
CASE(eCornerTopRight, false, eCornerTopRightX);
CASE(eCornerTopRight, true, eCornerTopRightY);
CASE(eCornerBottomRight, false, eCornerBottomRightX);
CASE(eCornerBottomRight, true, eCornerBottomRightY);
CASE(eCornerBottomLeft, false, eCornerBottomLeftX);
CASE(eCornerBottomLeft, true, eCornerBottomLeftY);
#undef CASE

// Validation of SideToFullCorner.
#define CASE(side, second, result)                        \
  static_assert(SideToFullCorner(side, second) == result, \
                "SideToFullCorner is wrong")
CASE(eSideTop, false, eCornerTopLeft);
CASE(eSideTop, true, eCornerTopRight);

CASE(eSideRight, false, eCornerTopRight);
CASE(eSideRight, true, eCornerBottomRight);

CASE(eSideBottom, false, eCornerBottomRight);
CASE(eSideBottom, true, eCornerBottomLeft);

CASE(eSideLeft, false, eCornerBottomLeft);
CASE(eSideLeft, true, eCornerTopLeft);
#undef CASE

// Validation of SideToHalfCorner.
#define CASE(side, second, parallel, result)                        \
  static_assert(SideToHalfCorner(side, second, parallel) == result, \
                "SideToHalfCorner is wrong")
CASE(eSideTop, false, true, eCornerTopLeftX);
CASE(eSideTop, false, false, eCornerTopLeftY);
CASE(eSideTop, true, true, eCornerTopRightX);
CASE(eSideTop, true, false, eCornerTopRightY);

CASE(eSideRight, false, false, eCornerTopRightX);
CASE(eSideRight, false, true, eCornerTopRightY);
CASE(eSideRight, true, false, eCornerBottomRightX);
CASE(eSideRight, true, true, eCornerBottomRightY);

CASE(eSideBottom, false, true, eCornerBottomRightX);
CASE(eSideBottom, false, false, eCornerBottomRightY);
CASE(eSideBottom, true, true, eCornerBottomLeftX);
CASE(eSideBottom, true, false, eCornerBottomLeftY);

CASE(eSideLeft, false, false, eCornerBottomLeftX);
CASE(eSideLeft, false, true, eCornerBottomLeftY);
CASE(eSideLeft, true, false, eCornerTopLeftX);
CASE(eSideLeft, true, true, eCornerTopLeftY);
#undef CASE