spline.h

//##################################################################################################
//
// Copyright (c) 2024 Beijing Qiongqi Tech Co.,Ltd. All rights reserved. 
 
// This source code is confidential and proprietary to Beijing Qiongqi Tech Co.,Ltd(The Holder). 
// Any unauthorized use, copying, modification, or distribution of the code is strictly prohibited. 
// Any user shall obtain authorizaition from the Holder before modifying the source code. And the user shall not
// sublicense, sell, distribute, or transfer the source code, whether in original or modified form, to any third party
// without the prior written consent of the Holder.
 
// This copyright notice and permission grant shall be included in all copies or substantial portions of the source code.
 
// Author  Cumulia Illustrator
// Date    2024-10-31
// Version V1.1.0
//##################################################################################################
 
#pragma once
 
#include <cilcore.h>
#include <vector>
 
 
namespace cil
{
 
    class BSplineCurve 
    {
    public:
        std::vector<Vector3f> control_points; // 控制点
        std::vector<float> knot_vector; // 结点向量
        int degree; // 曲线次数
 
        enum class Boundary
        {
            OPEN,
            CLOSED,
            CLAMPED
        };
        Boundary boundary;
 
        //Constructor
        
        BSplineCurve();
        
        BSplineCurve(std::vector<Vector3f> points, int k = 3, Boundary bound = BSplineCurve::Boundary::CLAMPED);
        // 计算基函数值
        float BasisFunction(int i, int k, float u);
 
        // 计算B 样条曲线上的点
        Vector3f CalculatePoint(float u);
    };
 
    class FitBSplineCurve : public BSplineCurve
    {
    public:
        std::vector<Vector3f> fit_points; // 插值点
 
        FitBSplineCurve(std::vector<Vector3f> points, Boundary bound = BSplineCurve::Boundary::CLAMPED);
 
        // 计算端点的斜率
        void BesselTanget(const Vector3f& p0,const Vector3f& p1,const Vector3f& p2, 
                        Vector3f& p0deriv,Vector3f& p1deriv,Vector3f& p2deriv);
 
    };
   
    std::shared_ptr<Geometry> _spline(const std::vector<Vector3f> control_points, int degree, BSplineCurve::Boundary boundary, const int slices);
    std::shared_ptr<Geometry> _spline_fit(const std::vector<Vector3f> fit_points, BSplineCurve::Boundary boundary, const int slices);
}