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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
#ifndef NSCOORD_H
#define NSCOORD_H
#include <algorithm>
#include <cstdint>
#include <cstdlib>
#include <math.h>
#include "mozilla/Assertions.h"
#include "mozilla/gfx/Coord.h"
#include "nsMathUtils.h"
/*
* Basic type used for the geometry classes.
*
* Normally all coordinates are maintained in an app unit coordinate
* space. An app unit is 1/60th of a CSS device pixel, which is, in turn
* an integer number of device pixels, such at the CSS DPI is as close to
* 96dpi as possible.
*/
using nscoord = int32_t;
inline constexpr nscoord nscoord_MAX = (1 << 30) - 1;
inline constexpr nscoord nscoord_MIN = -nscoord_MAX;
namespace mozilla {
struct AppUnit {};
// Declare AppUnit as a coordinate system tag.
template <>
struct IsPixel<AppUnit> : std::true_type {};
namespace detail {
template <typename Rep>
struct AuCoordImpl : public gfx::IntCoordTyped<AppUnit, Rep> {
using Super = gfx::IntCoordTyped<AppUnit, Rep>;
constexpr AuCoordImpl() : Super() {}
constexpr MOZ_IMPLICIT AuCoordImpl(Rep aValue) : Super(aValue) {}
constexpr MOZ_IMPLICIT AuCoordImpl(Super aValue) : Super(aValue) {}
template <typename F>
static AuCoordImpl FromRound(F aValue) {
// Note: aValue is *not* rounding to nearest integer if it is negative. See
return AuCoordImpl(std::floor(aValue + 0.5f));
}
template <typename F>
static AuCoordImpl FromTruncate(F aValue) {
return AuCoordImpl(std::trunc(aValue));
}
template <typename F>
static AuCoordImpl FromCeil(F aValue) {
return AuCoordImpl(std::ceil(aValue));
}
template <typename F>
static AuCoordImpl FromFloor(F aValue) {
return AuCoordImpl(std::floor(aValue));
}
// Note: this returns the result of the operation, without modifying the
// original value.
[[nodiscard]] AuCoordImpl ToMinMaxClamped() const {
return std::clamp(this->value, kMin, kMax);
}
static constexpr Rep kMax = nscoord_MAX;
static constexpr Rep kMin = nscoord_MIN;
};
} // namespace detail
using AuCoord = detail::AuCoordImpl<int32_t>;
using AuCoord64 = detail::AuCoordImpl<int64_t>;
} // namespace mozilla
/**
* Divide aSpace by aN. Assign the resulting quotient to aQuotient and
* return the remainder.
*/
inline nscoord NSCoordDivRem(nscoord aSpace, size_t aN, nscoord* aQuotient) {
div_t result = div(aSpace, aN);
*aQuotient = nscoord(result.quot);
return nscoord(result.rem);
}
inline nscoord NSCoordMulDiv(nscoord aMult1, nscoord aMult2, nscoord aDiv) {
return (int64_t(aMult1) * int64_t(aMult2) / int64_t(aDiv));
}
inline nscoord NSToCoordRound(float aValue) {
#if defined(XP_WIN) && defined(_M_IX86) && !defined(__GNUC__) && \
!defined(__clang__)
return NS_lroundup30(aValue);
#else
return nscoord(floorf(aValue + 0.5f));
#endif /* XP_WIN && _M_IX86 && !__GNUC__ */
}
inline nscoord NSToCoordRound(double aValue) {
#if defined(XP_WIN) && defined(_M_IX86) && !defined(__GNUC__) && \
!defined(__clang__)
return NS_lroundup30((float)aValue);
#else
return nscoord(floor(aValue + 0.5f));
#endif /* XP_WIN && _M_IX86 && !__GNUC__ */
}
inline nscoord NSToCoordRoundWithClamp(float aValue) {
// Bounds-check before converting out of float, to avoid overflow
if (aValue >= float(nscoord_MAX)) {
return nscoord_MAX;
}
if (aValue <= float(nscoord_MIN)) {
return nscoord_MIN;
}
return NSToCoordRound(aValue);
}
inline nscoord NSToCoordRoundWithClamp(double aValue) {
// Bounds-check before converting out of double, to avoid overflow
if (aValue >= double(nscoord_MAX)) {
return nscoord_MAX;
}
if (aValue <= double(nscoord_MIN)) {
return nscoord_MIN;
}
return NSToCoordRound(aValue);
}
/**
* Returns aCoord * aScale, capping the product to nscoord_MAX or nscoord_MIN as
* appropriate for the signs of aCoord and aScale. If requireNotNegative is
* true, this method will enforce that aScale is not negative; use that
* parametrization to get a check of that fact in debug builds.
*/
inline nscoord _nscoordSaturatingMultiply(nscoord aCoord, float aScale,
bool requireNotNegative) {
if (requireNotNegative) {
MOZ_ASSERT(aScale >= 0.0f,
"negative scaling factors must be handled manually");
}
float product = aCoord * aScale;
if (requireNotNegative ? aCoord > 0 : (aCoord > 0) == (aScale > 0))
return NSToCoordRoundWithClamp(
std::min<float>((float)nscoord_MAX, product));
return NSToCoordRoundWithClamp(std::max<float>((float)nscoord_MIN, product));
}
/**
* Returns aCoord * aScale, capping the product to nscoord_MAX or nscoord_MIN as
* appropriate for the sign of aCoord. This method requires aScale to not be
* negative; use this method when you know that aScale should never be
* negative to get a sanity check of that invariant in debug builds.
*/
inline nscoord NSCoordSaturatingNonnegativeMultiply(nscoord aCoord,
float aScale) {
return _nscoordSaturatingMultiply(aCoord, aScale, true);
}
/**
* Returns aCoord * aScale, capping the product to nscoord_MAX or nscoord_MIN as
* appropriate for the signs of aCoord and aScale.
*/
inline nscoord NSCoordSaturatingMultiply(nscoord aCoord, float aScale) {
return _nscoordSaturatingMultiply(aCoord, aScale, false);
}
/**
* Returns a + b, capping the sum to nscoord_MAX.
*
* This function assumes that neither argument is nscoord_MIN.
*/
inline nscoord NSCoordSaturatingAdd(nscoord a, nscoord b) {
if (a == nscoord_MAX || b == nscoord_MAX) {
// infinity + anything = anything + infinity = infinity
return nscoord_MAX;
} else {
// a + b = a + b
// Cap the result, just in case we're dealing with numbers near nscoord_MAX
return std::min(nscoord_MAX, a + b);
}
}
/**
* Returns a - b, gracefully handling cases involving nscoord_MAX.
* This function assumes that neither argument is nscoord_MIN.
*
* The behavior is as follows:
*
* a) infinity - infinity -> infMinusInfResult
* b) N - infinity -> 0 (unexpected -- triggers NOTREACHED)
* c) infinity - N -> infinity
* d) N1 - N2 -> N1 - N2
*/
inline nscoord NSCoordSaturatingSubtract(nscoord a, nscoord b,
nscoord infMinusInfResult) {
if (b == nscoord_MAX) {
if (a == nscoord_MAX) {
// case (a)
return infMinusInfResult;
} else {
// case (b)
return 0;
}
} else {
if (a == nscoord_MAX) {
// case (c) for integers
return nscoord_MAX;
} else {
// case (d) for integers
// Cap the result, in case we're dealing with numbers near nscoord_MAX
return std::min(nscoord_MAX, a - b);
}
}
}
inline float NSCoordToFloat(nscoord aCoord) { return (float)aCoord; }
/*
* Coord Rounding Functions
*/
inline nscoord NSToCoordFloor(float aValue) { return nscoord(floorf(aValue)); }
inline nscoord NSToCoordFloor(double aValue) { return nscoord(floor(aValue)); }
inline nscoord NSToCoordFloorClamped(float aValue) {
// Bounds-check before converting out of float, to avoid overflow
if (aValue >= float(nscoord_MAX)) {
return nscoord_MAX;
}
if (aValue <= float(nscoord_MIN)) {
return nscoord_MIN;
}
return NSToCoordFloor(aValue);
}
inline nscoord NSToCoordCeil(float aValue) { return nscoord(ceilf(aValue)); }
inline nscoord NSToCoordCeil(double aValue) { return nscoord(ceil(aValue)); }
inline nscoord NSToCoordCeilClamped(double aValue) {
// Bounds-check before converting out of double, to avoid overflow
if (aValue >= nscoord_MAX) {
return nscoord_MAX;
}
if (aValue <= nscoord_MIN) {
return nscoord_MIN;
}
return NSToCoordCeil(aValue);
}
// The NSToCoordTrunc* functions remove the fractional component of
// aValue, and are thus equivalent to NSToCoordFloor* for positive
// values and NSToCoordCeil* for negative values.
inline nscoord NSToCoordTrunc(float aValue) {
// There's no need to use truncf() since it matches the default
// rules for float to integer conversion.
return nscoord(aValue);
}
inline nscoord NSToCoordTrunc(double aValue) {
// There's no need to use trunc() since it matches the default
// rules for float to integer conversion.
return nscoord(aValue);
}
inline nscoord NSToCoordTruncClamped(float aValue) {
// Bounds-check before converting out of float, to avoid overflow
if (aValue >= float(nscoord_MAX)) {
return nscoord_MAX;
}
if (aValue <= float(nscoord_MIN)) {
return nscoord_MIN;
}
return NSToCoordTrunc(aValue);
}
inline nscoord NSToCoordTruncClamped(double aValue) {
// Bounds-check before converting out of double, to avoid overflow
if (aValue >= float(nscoord_MAX)) {
return nscoord_MAX;
}
if (aValue <= float(nscoord_MIN)) {
return nscoord_MIN;
}
return NSToCoordTrunc(aValue);
}
/*
* Int Rounding Functions
*/
inline int32_t NSToIntFloor(float aValue) { return int32_t(floorf(aValue)); }
inline int32_t NSToIntCeil(float aValue) { return int32_t(ceilf(aValue)); }
inline int32_t NSToIntRound(float aValue) { return NS_lroundf(aValue); }
inline int32_t NSToIntRound(double aValue) { return NS_lround(aValue); }
inline int32_t NSToIntRoundUp(double aValue) {
return int32_t(floor(aValue + 0.5));
}
/*
* App Unit/Pixel conversions
*/
inline nscoord NSFloatPixelsToAppUnits(float aPixels, float aAppUnitsPerPixel) {
return NSToCoordRoundWithClamp(aPixels * aAppUnitsPerPixel);
}
inline nscoord NSIntPixelsToAppUnits(int32_t aPixels,
int32_t aAppUnitsPerPixel) {
// The cast to nscoord makes sure we don't overflow if we ever change
// nscoord to float
nscoord r = aPixels * (nscoord)aAppUnitsPerPixel;
return r;
}
inline float NSAppUnitsToFloatPixels(nscoord aAppUnits,
float aAppUnitsPerPixel) {
return (float(aAppUnits) / aAppUnitsPerPixel);
}
inline double NSAppUnitsToDoublePixels(nscoord aAppUnits,
double aAppUnitsPerPixel) {
return (double(aAppUnits) / aAppUnitsPerPixel);
}
inline int32_t NSAppUnitsToIntPixels(nscoord aAppUnits,
float aAppUnitsPerPixel) {
return NSToIntRound(float(aAppUnits) / aAppUnitsPerPixel);
}
inline float NSCoordScale(nscoord aCoord, int32_t aFromAPP, int32_t aToAPP) {
return (NSCoordToFloat(aCoord) * aToAPP) / aFromAPP;
}
/// handy constants
#define TWIPS_PER_POINT_INT 20
#define TWIPS_PER_POINT_FLOAT 20.0f
#define POINTS_PER_INCH_INT 72
#define POINTS_PER_INCH_FLOAT 72.0f
#define CM_PER_INCH_FLOAT 2.54f
#define MM_PER_INCH_FLOAT 25.4f
/*
* Twips/unit conversions
*/
inline float NSUnitsToTwips(float aValue, float aPointsPerUnit) {
return aValue * aPointsPerUnit * TWIPS_PER_POINT_FLOAT;
}
inline float NSTwipsToUnits(float aTwips, float aUnitsPerPoint) {
return (aTwips * (aUnitsPerPoint / TWIPS_PER_POINT_FLOAT));
}
/// Unit conversion macros
//@{
#define NS_POINTS_TO_TWIPS(x) NSUnitsToTwips((x), 1.0f)
#define NS_INCHES_TO_TWIPS(x) \
NSUnitsToTwips((x), POINTS_PER_INCH_FLOAT) // 72 points per inch
#define NS_MILLIMETERS_TO_TWIPS(x) \
NSUnitsToTwips((x), (POINTS_PER_INCH_FLOAT * 0.03937f))
#define NS_POINTS_TO_INT_TWIPS(x) NSToIntRound(NS_POINTS_TO_TWIPS(x))
#define NS_INCHES_TO_INT_TWIPS(x) NSToIntRound(NS_INCHES_TO_TWIPS(x))
#define NS_TWIPS_TO_INCHES(x) NSTwipsToUnits((x), 1.0f / POINTS_PER_INCH_FLOAT)
#define NS_TWIPS_TO_MILLIMETERS(x) \
NSTwipsToUnits((x), 1.0f / (POINTS_PER_INCH_FLOAT * 0.03937f))
//@}
#endif /* NSCOORD_H */