libcruft-util/noise/fractal/hetero.ipp

105 lines
2.9 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 2012-2015 Danny Robson <danny@nerdcruft.net>
*/
#ifdef __UTIL_NOISE_FRACTAL_HETERO_IPP
#error
#endif
#define __UTIL_NOISE_FRACTAL_HETERO_IPP
namespace util { namespace noise { namespace fractal {
///////////////////////////////////////////////////////////////////////////
template <typename T, typename B>
hetero<T,B>::hetero(seed_t _seed,
unsigned _octaves,
T _H,
T _frequency,
T _lacunarity,
T _amplitude,
T _gain,
T _offset):
base<T,B> (_seed,
_octaves,
_H,
_frequency,
_lacunarity,
_amplitude,
_gain),
m_offset (_offset)
{ ; }
//-------------------------------------------------------------------------
template <typename T, typename B>
hetero<T,B>::hetero (seed_t _seed):
hetero<T,B> (_seed,
DEFAULT_OCTAVES,
DEFAULT_H,
DEFAULT_FREQUENCY,
DEFAULT_LACUNARITY,
DEFAULT_AMPLITUDE,
DEFAULT_GAIN,
DEFAULT_OFFSET)
{ ; }
///////////////////////////////////////////////////////////////////////////
template <typename T, typename B>
constexpr T
hetero<T,B>::offset (void) const
{
return m_offset;
}
//-------------------------------------------------------------------------
template <typename T, typename B>
T
hetero<T,B>::offset (T _offset)
{
return m_offset = _offset;
}
///////////////////////////////////////////////////////////////////////////
template <typename T, typename B>
T
hetero<T,B>::operator() (util::point<2,T> p) const
{
T scale = this->m_invAH;
p *= this->m_frequency;
T result = (this->m_basis (p) + m_offset) * scale;
p *= this->m_lacunarity;
T increment = 0;
for (size_t i = 1; i < this->m_octaves; ++i) {
scale *= this->m_invGH;
increment = this->m_basis (p) + m_offset;
increment *= scale;
increment *= result;
result += increment;
p += T{1};
p *= this->m_lacunarity;
}
return result;
}
} } }