86 lines
2.1 KiB
C++
86 lines
2.1 KiB
C++
/*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
* Copyright 2014 Danny Robson <danny@nerdcruft.net>
|
|
*/
|
|
|
|
#ifndef __UTIL_MATHS_IPP
|
|
#define __UTIL_MATHS_IPP
|
|
#else
|
|
#error "Include only once"
|
|
#endif
|
|
|
|
#include <type_traits>
|
|
|
|
//-----------------------------------------------------------------------------
|
|
template <typename T, typename U>
|
|
typename std::common_type<T,U>::type
|
|
align (T value, U size) {
|
|
static_assert (std::is_integral<T>::value, "align requires integral types");
|
|
static_assert (std::is_integral<U>::value, "align requires integral types");
|
|
|
|
return divup (value, size) * size;
|
|
}
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
template <typename T>
|
|
constexpr T
|
|
pow (T x, unsigned y)
|
|
{
|
|
return y == 0 ? 1 : x * pow (x, y - 1);
|
|
}
|
|
|
|
|
|
///----------------------------------------------------------------------------
|
|
/// Return a unit type with a sign that matches the provided value
|
|
///
|
|
/// We were using __builtin_signbit for the potential speedboost, but it causes
|
|
/// problems with constexpr under clang. If you need speed then you'll probably
|
|
/// have to handcode something.
|
|
constexpr int
|
|
sign (int v)
|
|
{
|
|
return std::signbit (v) ? -1 : 1;
|
|
}
|
|
|
|
constexpr float
|
|
sign (float v)
|
|
{
|
|
return std::signbit (v) ? -1.f : 1.f;
|
|
}
|
|
|
|
|
|
constexpr double
|
|
sign (double v)
|
|
{
|
|
return std::signbit (v) ? -1. : 1.f;
|
|
}
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
template <>
|
|
struct constants<float>
|
|
{
|
|
static constexpr float PI = PI_f;
|
|
static constexpr float E = E_f;
|
|
};
|
|
|
|
|
|
template <>
|
|
struct constants<double>
|
|
{
|
|
static constexpr double PI = PI_d;
|
|
static constexpr double E = E_d;
|
|
};
|