Flood-Accumulation

Course Work for 2023 Fall Develop a GIS from bottom up

English

Overview

This repository contains the course work for Develop a GIS from bottom up, focusing on flood accumulation calculations. It has been developed using C++20 standards and is designed to be compiled and run in Visual Studio 2022 Community X64 debug mode.
It can process a 696-line, 493-column 32-bit DEM dataset on a single thread on a laptop Intel i7-13700HX 2100MHz chip with no more than 6s, 23MB memory.

Getting Started

1. Solution Compilation

   • The src folder contains the complete project solution .sln file.
   • Compile and run the solution after compiling it. It has been successfully compiled and tested in Visual Studio 2022 Community X64 debug mode.

2. Algorithm and Logic

   • The presentation.pdf document provides a detailed explanation of the algorithms and logic implemented in the code.

3. Data Sets

   • The dataset folder contains two example DEM (Digital Elevation Model) data sets, each with a scale of 1e5.
   • The Test result folder contains the data results after running the solution. You could extract the streams and visualize them more beautifully using ArcGIS.

4. Software Requirements

   • GDAL 3.X Library: To run this solution, you need to compile the GDAL 3.X library locally.
   • IDE Compatibility: You can use any C/C++ compatible IDE to open and compile this file.
   • Compiler Standard: Please ensure your compiler supports C++20 standards（maybe no need. I cannot remember whether I had used C++20 API OvO）.

5. Additional Materiel

   • The Fill.txt file contains a small component std::vector<vector<float>> Fill, which implements a depression filling method using a priority queue with a time complexity of O(n).
   • Note: This method has a memory management issue and has not been merged into the final solution. But I considered it elegant and, therefore, it was finally retained (^ v ^). It can solve my test samples but failed to deal with real-world DEM in the 'dataset' folder. (T T)

中文

概述

此仓库是一个专注于高速洪水累积量计算的 地理信息系统底层开发 作业。使用C++20标准开发，并在Visual Studio 2022 Community X64 Debug模式下编译和运行通过。在笔记本Intel i7-13700HX 2100MHz芯片上单线程处理一个696行， 493列，32 Bit的DEM数据只需要不超过6s，23MB内存。

开始使用

1. 解决方案编译

   • src 文件夹包含了完整的项目解决方案 .sln 文件。
   • 编译后运行解决方案。它已在Visual Studio 2022 Community X64调试模式下成功编译和测试。

2. 算法和逻辑

   • presentation.pdf 文档提供了代码中实现的算法和逻辑的详细说明。

3. 数据集

   • dataset 文件夹包含了两个示例的DEM（数字高程模型）数据集，数据集的尺寸大约为1e5级别。
   • Test result 文件夹包含了运行解决方案后的数据结果。你可以在ArcGIS中进一步提取流线和可视化。

4. 软件要求

   • GDAL 3.X库：要运行此解决方案，您需要在本地编译GDAL 3.X库。
   • IDE兼容性：您可以使用任何兼容C/C++的IDE打开和编译此文件。
   • 编译器标准：请确保您的编译器支持C++20标准（其实不用，我感觉我都没怎么用20的特性 OvO）。

5. 额外材料

   • Fill.txt 文件包含了一个函数 std::vector<vector<float>> Fill，它使用优先队列实现了一种填洼方法，时间复杂度为O(n)。
   • 注意：该方法没有在项目中部署，但我认为这种方法非常优雅，因此保留了txt版本(^ v ^)。他可以应对我的测试样例，但是无法应对dataset中的真实世界DEM。(T T)

References

1. Zhou, G., Wei, H., & Fu, S. (2019). A fast and simple algorithm for calculating flow accumulation matrices from raster digital elevation. Frontiers of Earth Science: English Edition, 13(2), 10.
2. Planchon, O., & Frédéric Darboux. (2002). A fast, simple, and versatile algorithm to fill the depressions of digital elevation models. Catena, 46(2-3), 159-176.
3. Wang, L., & Liu, H. (2006). An efficient method for identifying and filling surface depressions in digital elevation models for hydrologic analysis and modeling. International Journal of Geographical Information Science.

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How to compile GDAL 3.X for local C++？
GDAL with Visual Studio 2022