64 lines
2.1 KiB
C++
64 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,
|
|
* WITHOUvalue_t 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>
|
|
*/
|
|
|
|
#ifndef __UTIL_NOISE_FRACTAL_FBM_HPP
|
|
#define __UTIL_NOISE_FRACTAL_FBM_HPP
|
|
|
|
#include <cstdint>
|
|
|
|
#include "base.hpp"
|
|
#include "../../point.hpp"
|
|
|
|
namespace util { namespace noise { namespace fractal {
|
|
/// Fractal Brownian Motion summation.
|
|
///
|
|
/// Sum progressive layers of a noise basis with scaling frequency
|
|
/// and amplitude.
|
|
///
|
|
/// octaves: count of layers to be summed
|
|
/// frequency: point scaling factor for the base octave
|
|
/// lacunarity: per octave frequency scaling factor
|
|
/// amplitude: maximum absolute value of the noise
|
|
/// gain: per octave amplitude scaling factor. typically 1/f.
|
|
template <class B>
|
|
struct fbm : public base<B> {
|
|
using value_t = typename base<B>::value_t;
|
|
using point_t = typename base<B>::point_t;
|
|
|
|
static constexpr unsigned DEFAULT_OCTAVES = 8;
|
|
static constexpr value_t DEFAULT_H = 1;
|
|
static constexpr value_t DEFAULT_FREQUENCY = value_t(0.1);
|
|
static constexpr value_t DEFAULT_LACUNARITY = 2;
|
|
static constexpr value_t DEFAULT_AMPLITUDE = 1;
|
|
static constexpr value_t DEFAULT_GAIN = 1 / DEFAULT_LACUNARITY;
|
|
|
|
fbm (seed_t seed,
|
|
unsigned octaves,
|
|
value_t H,
|
|
value_t frequency,
|
|
value_t lacunarity,
|
|
value_t amplitude,
|
|
value_t gain);
|
|
explicit fbm (seed_t = 0);
|
|
|
|
value_t operator() (point_t) const noexcept;
|
|
};
|
|
} } }
|
|
|
|
#include "fbm.ipp"
|
|
|
|
#endif
|