100 lines
2.3 KiB
C++
100 lines
2.3 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 2011-2016 Danny Robson <danny@nerdcruft.net>
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*/
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#if defined(CRUFT_UTIL_QUATERNION_IPP)
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#error
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#endif
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#define CRUFT_UTIL_QUATERNION_IPP
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#include <cmath>
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///////////////////////////////////////////////////////////////////////////////
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template <typename T>
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constexpr
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util::quaternion<T>
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util::quaternion<T>::identity (void)
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{
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return { 1, 0, 0, 0 };
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}
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///////////////////////////////////////////////////////////////////////////////
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template <typename T>
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constexpr
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T
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util::norm2 (quaternion<T> q)
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{
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return q.w * q.w +
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q.x * q.x +
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q.y * q.y +
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q.z * q.z;
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}
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//-----------------------------------------------------------------------------
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template <typename T>
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constexpr
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T
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util::norm (quaternion<T> q)
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{
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return std::sqrt (norm2 (q));
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}
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//-----------------------------------------------------------------------------
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template <typename T>
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constexpr
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bool
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util::is_normalised (quaternion<T> q)
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{
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return almost_equal (T{1}, norm2 (q));
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}
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//-----------------------------------------------------------------------------
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template <typename T>
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constexpr
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util::quaternion<T>
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util::normalised (quaternion<T> q)
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{
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return q / norm (q);
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}
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///////////////////////////////////////////////////////////////////////////////
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template <typename T>
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constexpr
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util::quaternion<T>
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util::operator/ (quaternion<T> q, T t)
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{
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return { q.w / t, q.x / t, q.y / t, q.z / t };
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}
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///////////////////////////////////////////////////////////////////////////////
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template <typename T>
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constexpr
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bool
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util::operator== (quaternion<T> a, quaternion<T> b)
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{
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return exactly_equal (a.w, b.w) &&
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exactly_equal (a.x, b.x) &&
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exactly_equal (a.y, b.y) &&
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exactly_equal (a.z, b.z);
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}
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