some working variables need to be precomputed. it makes sense to do this in a base class.
85 lines
2.1 KiB
C++
85 lines
2.1 KiB
C++
/*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Copyright 2015 Danny Robson <danny@nerdcruft.net>
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*/
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#ifndef __UTIL_NOISE_FRACTAL_BASE_HPP
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#define __UTIL_NOISE_FRACTAL_BASE_HPP
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#include <cstdint>
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#include "../../point.hpp"
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namespace util { namespace noise { namespace fractal {
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/// Fractal Brownian Motion summation.
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///
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/// Sum progressive layers of a noise basis with scaling frequency
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/// and amplitude.
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///
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/// octaves: count of layers to be summed
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/// frequency: point scaling factor for the base octave
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/// lacunarity: per octave frequency scaling factor
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/// amplitude: maximum absolute value of the noise
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/// gain: per octave amplitude scaling factor. typically 1/f.
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template <typename T, typename B>
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struct base {
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using seed_t = uint64_t;
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// constructors
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base (seed_t,
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unsigned octaves,
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T H,
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T frequency,
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T lacunarity,
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T amplitude,
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T gain);
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// accessors
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constexpr unsigned octaves (void) const;
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unsigned octaves (unsigned);
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constexpr T H (void) const;
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T H (T);
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constexpr T frequency (void) const;
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T frequency (T);
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constexpr T lacunarity (void) const;
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T lacunarity (T);
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constexpr seed_t seed (void) const;
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seed_t seed (seed_t);
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protected:
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unsigned m_octaves;
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T m_H;
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T m_frequency;
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T m_lacunarity;
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T m_amplitude;
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T m_gain;
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B m_basis;
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T m_invAH;
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T m_invGH;
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};
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} } }
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#include "base.ipp"
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#endif
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