diff --git a/libs/kimath/CMakeLists.txt b/libs/kimath/CMakeLists.txt index 3550ca760d..e61158f210 100644 --- a/libs/kimath/CMakeLists.txt +++ b/libs/kimath/CMakeLists.txt @@ -17,6 +17,9 @@ set( KIMATH_SRCS src/geometry/shape_rect.cpp src/geometry/shape_compound.cpp src/geometry/shape_segment.cpp + + + src/math/util.cpp ) # Include the other smaller math libraries in this one for convenience diff --git a/libs/kimath/include/math/util.h b/libs/kimath/include/math/util.h index e76b84dd18..08a00a0793 100644 --- a/libs/kimath/include/math/util.h +++ b/libs/kimath/include/math/util.h @@ -1,7 +1,6 @@ /* * This program source code file is part of KICAD, a free EDA CAD application. * - * Copyright (C) 2021 KiCad Developers, see AUTHORS.txt for contributors. * Copyright (c) 2005 Michael Niedermayer * Copyright (C) CERN * @author Tomasz Wlostowski @@ -31,7 +30,6 @@ #include #include #include -#include #include #include @@ -93,26 +91,10 @@ constexpr ret_type KiROUND( fp_type v ) * Scales a number (value) by rational (numerator/denominator). Numerator must be <= denominator. */ -template -T rescale( T aNumerator, T aValue, T aDenominator, std::false_type ) -{ - /// Rescales for floating point, casting up to double - return static_cast( aNumerator ) * static_cast( aValue ) - / static_cast( aDenominator ); -} - -template -T rescale( T aNumerator, T aValue, T aDenominator, std::true_type ) -{ - /// Rescales for integers casting to double and handling rounding to nearest - return KiROUND( static_cast( aNumerator ) * static_cast( aValue ) - / static_cast( aDenominator ) ); -} - template T rescale( T aNumerator, T aValue, T aDenominator ) { - return rescale( aNumerator, aValue, aDenominator, std::is_integral() ); + return aNumerator * aValue / aDenominator; } template @@ -121,4 +103,11 @@ int sign( T val ) return ( T( 0 ) < val) - ( val < T( 0 ) ); } +// explicit specializations for integer types, taking care of overflow. +template <> +int rescale( int aNumerator, int aValue, int aDenominator ); + +template <> +int64_t rescale( int64_t aNumerator, int64_t aValue, int64_t aDenominator ); + #endif // UTIL_H diff --git a/libs/kimath/src/math/util.cpp b/libs/kimath/src/math/util.cpp new file mode 100644 index 0000000000..51a09e1d46 --- /dev/null +++ b/libs/kimath/src/math/util.cpp @@ -0,0 +1,91 @@ +/* + * This program source code file is part of KICAD, a free EDA CAD application. + * + * Copyright (c) 2005 Michael Niedermayer + * Copyright (C) CERN + * @author Tomasz Wlostowski + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, you may find one here: + * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html + * or you may search the http://www.gnu.org website for the version 2 license, + * or you may write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA + */ + +#include +#include +#include +#include + +template<> +int rescale( int aNumerator, int aValue, int aDenominator ) +{ + return (int) ( (int64_t) aNumerator * (int64_t) aValue / (int64_t) aDenominator ); +} + + +template<> +int64_t rescale( int64_t aNumerator, int64_t aValue, int64_t aDenominator ) +{ +#ifdef __x86_64__ + return ( (__int128_t) aNumerator * (__int128_t) aValue ) / aDenominator; +#else + int64_t r = 0; + int64_t sign = ( ( aNumerator < 0 ) ? -1 : 1 ) * ( aDenominator < 0 ? -1 : 1 ) * + ( aValue < 0 ? -1 : 1 ); + + int64_t a = std::abs( aNumerator ); + int64_t b = std::abs( aValue ); + int64_t c = std::abs( aDenominator ); + + r = c / 2; + + if( b <= INT_MAX && c <= INT_MAX ) + { + if( a <= INT_MAX ) + return sign * ( ( a * b + r ) / c ); + else + return sign * ( a / c * b + ( a % c * b + r ) / c); + } + else + { + uint64_t a0 = a & 0xFFFFFFFF; + uint64_t a1 = a >> 32; + uint64_t b0 = b & 0xFFFFFFFF; + uint64_t b1 = b >> 32; + uint64_t t1 = a0 * b1 + a1 * b0; + uint64_t t1a = t1 << 32; + int i; + + a0 = a0 * b0 + t1a; + a1 = a1 * b1 + ( t1 >> 32 ) + ( a0 < t1a ); + a0 += r; + a1 += a0 < (uint64_t)r; + + for( i = 63; i >= 0; i-- ) + { + a1 += a1 + ( ( a0 >> i ) & 1 ); + t1 += t1; + + if( (uint64_t) c <= a1 ) + { + a1 -= c; + t1++; + } + } + + return t1 * sign; + } +#endif +}