Add PathProcessing standalone library for spline, path, and normalization operations

[Copilot]

Overview

Successfully created a standalone C++ library for path processing operations extracted from the MPCC codebase. The library includes spline interpolation, path parameterization, track management, and normalization functionality.

What Was Created

Created PathProcessing library in C++/PathProcessing/ with 19 files (~1,800 lines of code):

Core Components

1. Cubic Spline (cubic_spline.h/cpp) - Natural cubic spline interpolation with first and second derivative computation
2. Arc Length Spline (arc_length_spline.h/cpp) - Arc-length parametrized 2D splines with iterative refinement and Newton-method projection
3. Track (track.h/cpp) - Track data management from JSON files with inner/outer boundaries
4. Normalization (normalization.h/cpp) - Variable scaling for optimization with diagonal transformation matrices

Configuration & Build

• path_processing.h - Master header file
• path_processing_config.h - Minimal configuration without MPC dependencies
• CMakeLists.txt - Flexible build configuration with standalone and integrated modes

Documentation

• README.md - Comprehensive bilingual documentation (English/Chinese)
• MIGRATION.md - Migration guide from original MPCC code
• SUMMARY.md - Complete feature summary and usage guide

Examples & Tests

• examples.cpp - Comprehensive usage examples for all components
• test_path_processing.cpp - Test program for validation

Key Features

• Self-contained: No dependencies on MPC-specific code (Cost, Model, Constraints)
• Minimal dependencies: Only requires Eigen3 and nlohmann/json
• Clean namespace: All code in mpcc::path_processing to avoid conflicts
• Safe code: Division by zero protection, proper error handling
• Portable: Flexible CMake configuration with find_package support

Improvements Over Original Code

1. Simplified types: Lightweight SimpleState (3 members) vs full State (10 members)
2. Lightweight parameters: SplineParams with only required fields vs full Param class
3. Fixed typos: Corrected method names (porjectOnSpline → projectOnSpline, getPostion → getPosition)
4. Enhanced safety: Added epsilon checks for division by zero in normalization
5. Better error handling: Improved error messages and validation

Code Quality

• ✅ Code review completed and all issues addressed
• ✅ Security analysis passed (no vulnerabilities detected)
• ✅ Division by zero protection added
• ✅ File existence checks in examples
• ✅ Portable CMake configuration

Usage Example

#include "PathProcessing/path_processing.h"

using namespace mpcc::path_processing;

// Create arc-length spline
SplineParams params(1.0);
ArcLengthSpline spline(params);
spline.gen2DSpline(X, Y);

// Query spline
Eigen::Vector2d pos = spline.getPosition(5.0);
double length = spline.getLength();

// Project point onto spline
SimpleState state{1.0, 2.0, 0.0};
double s = spline.projectOnSpline(state);

The library is complete, production-ready, and can be used standalone or integrated back into the MPCC codebase.

Original prompt

提去c++文件夹中，用于养条化处理路径的代码，单独行程库】

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[Ciferplus]

已收到 谢谢

[Ciferplus]

@copilot 应该如何操作，才能提取c++文件夹中，用于样条化处理和参数化路径的代码，单独形成库，并且剥离无用的关联代码

[Copilot]

@copilot 应该如何操作，才能提取c++文件夹中，用于样条化处理和参数化路径的代码，单独形成库，并且剥离无用的关联代码

我理解您的需求。我将创建一个独立的库，包含：

1. 样条处理代码 (CubicSpline, ArcLengthSpline)
2. 路径参数化代码 (Track)
3. 路径标准化代码 (NormalizationParam)

这个库将：

• 移除对MPC特定代码的依赖（Cost, Model, Constraints等）
• 只保留必要的依赖：config.h, types.h中的基础类型
• 创建一个清晰的API供其他模块使用

我现在开始实施这个方案。

[Ciferplus]

@copilot 开始实施

[Copilot]

@copilot 开始实施

实施已完成！✅

PathProcessing库已经创建完成，包含19个文件：

核心组件：

• ✅ cubic_spline.h/cpp - 三次样条插值
• ✅ arc_length_spline.h/cpp - 弧长参数化样条
• ✅ track.h/cpp - 轨迹管理
• ✅ normalization.h/cpp - 标准化处理

文档：

• ✅ README.md - 中英文文档
• ✅ MIGRATION.md - 迁移指南
• ✅ SUMMARY.md - 完整总结
• ✅ examples.cpp - 使用示例

所有代码已提交（commits: 80fe750, 94ba310, 1ade06f, 3873040）

库已就绪，可以独立使用！