wide_int.h File Reference

128-bit integers for exact products of 64-bit coordinate deltas. More...

#include <bit>
#include <cmath>
#include <cstdint>
#include <math/vector2d.h>

Go to the source code of this file.

Namespaces
namespace	KIGEOM_WIDE

Typedefs
using	KI_INT128 = __int128
using	KI_UINT128 = unsigned __int128

Functions
double	KIGEOM_WIDE::WordsToDouble (int64_t aHi, uint64_t aLo)
	Nearest double to hi * 2^64 + lo, ties to even.
double	ToDouble (KI_INT128 aValue)
constexpr KI_INT128	CrossWide (const VECTOR2L &aA, const VECTOR2L &aB)
	Exact aA.x * aB.y - aA.y * aB.x.
constexpr KI_INT128	DotWide (const VECTOR2L &aA, const VECTOR2L &aB)
	Exact aA.x * aB.x + aA.y * aB.y.

Detailed Description

128-bit integers for exact products of 64-bit coordinate deltas.

Coordinates span 2^32 units, so deltas need 33 bits and their cross and dot products need 66. KI_INT128 holds those products exactly.

Definition in file wide_int.h.

Typedef Documentation

KI_INT128

using KI_INT128 = __int128

Definition at line 91 of file wide_int.h.

KI_UINT128

using KI_UINT128 = unsigned __int128

Definition at line 92 of file wide_int.h.

Function Documentation

CrossWide()

KI_INT128 CrossWide ( const VECTOR2L & aA, const VECTOR2L & aB )

constexpr

Exact aA.x * aB.y - aA.y * aB.x.

Never overflows for any int64 components.

Definition at line 104 of file wide_int.h.

References VECTOR2< T >::x, and VECTOR2< T >::y.

Referenced by BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), CalcArcCenter(), KIGEOM::OrientationSign(), and SEG::SquaredDistance().

DotWide()

KI_INT128 DotWide ( const VECTOR2L & aA, const VECTOR2L & aB )

constexpr

Exact aA.x * aB.x + aA.y * aB.y.

Overflows only when all four components are INT64_MIN.

Definition at line 113 of file wide_int.h.

References VECTOR2< T >::x, and VECTOR2< T >::y.

Referenced by BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), and BOOST_AUTO_TEST_CASE().

ToDouble()

double ToDouble ( KI_INT128 aValue )

inline

Definition at line 94 of file wide_int.h.

Referenced by BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), BOOST_AUTO_TEST_CASE(), CalcArcCenter(), SEG::SquaredDistance(), and TUNER_SLIDER::updateSlider().