66 lines
1.8 KiB
Plaintext
66 lines
1.8 KiB
Plaintext
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/*
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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 2012-2015 Danny Robson <danny@nerdcruft.net>
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*/
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#ifdef __UTIL_NOISE_FRACTAL_HMF_IPP
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#error
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#endif
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#define __UTIL_NOISE_FRACTAL_HMF_IPP
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namespace util { namespace noise { namespace fractal {
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//-------------------------------------------------------------------------
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template <typename T, typename B>
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hmf<T,B>::hmf ():
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H (0.25f),
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octaves (6),
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frequency (0.1f),
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lacunarity (2),
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offset (0.7f),
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amplitude (1),
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gain (1)
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{ ; }
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//-------------------------------------------------------------------------
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template <typename T, typename B>
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T
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hmf<T,B>::operator() (util::point<2,T> p) const
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{
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T exponents[octaves];
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for (size_t i = 0; i < octaves; ++i)
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exponents[i] = std::pow (std::pow (lacunarity, float (i)), -H);
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T result = 0;
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T signal = 0;
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T weight = 1;
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p *= frequency;
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for (size_t i = 0; i < octaves; ++i) {
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signal = (basis (p) + offset) * exponents[i];
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result += weight * signal;
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weight *= gain * signal;
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if (weight > 1)
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weight = 1;
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p *= lacunarity;
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}
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return result;
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}
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} } }
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