/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * 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.
 */

#ifndef API_BASE_MATH_SPLINE_H
#define API_BASE_MATH_SPLINE_H

#include <base/namespace.h>

BASE_BEGIN_NAMESPACE()
namespace Math {
/** @ingroup group_math_spline */
/** For hermite interpolation */
template <typename T>
inline constexpr T Hermite(T const& v1, T const& t1, T const& v2, T const& t2, float s)
{
    const float s2 = s * s;
    const float s3 = s2 * s;
    const float s23 = 2.f * s3;
    const float s32 = 3.f * s2;

    const float f1 = s23 - s32 + 1.f;
    const float f2 = -s23 + s32;
    const float f3 = s3 - 2.f * s2 + s;
    const float f4 = s3 - s2;

    return v1 * f1 + v2 * f2 + t1 * f3 + t2 * f4;
}
}  // namespace Math
BASE_END_NAMESPACE()

#endif  // API_BASE_MATH_SPLINE_H