MapboxGL CGCS2000 Coordinate Transformation Service

MapboxGL CGCS2000 坐标转换服务

Project Introduction

项目介绍

This is a Fastify-based web service that transforms WMTS tile requests from MapboxGL (Mercator projection) to CGCS2000 coordinate system, redraws PNG tiles and returns them to the MapboxGL frontend. Main features include:

这是一个基于Fastify的Web服务，用于将mapboxgl对墨卡托坐标系下wmts瓦片请求转化为对cgcs2000坐标系下的瓦片请求，重新绘制png瓦片后返回给mapboxgl前端。项目主要功能包括：

• 接收前端mapboxgl Mercator投影的瓦片请求 Receive tile requests from MapboxGL frontend in Mercator projection
• 将请求行列号转换为CGCS2000坐标系并计算瓦片四至坐标 Convert tile row/column numbers to CGCS2000 coordinate system and calculate tile bounds
• 从cgcs2000 的WMTS服务获取对应区域的瓦片 Fetch corresponding tiles from CGCS2000 WMTS service
• 合并多个瓦片并返回合成图像 Merge multiple tiles and return the composite image

Installation Steps

安装步骤

1. Ensure Node.js (recommended version 16+) and npm are installed 确保已安装Node.js (建议版本16+)和npm
2. Clone this repository 克隆本项目
3. Install dependencies: 安装依赖：

npm install

Usage

使用方法

1. Start the service 启动服务：

npm start

2. 服务默认运行在：http://localhost:3000
3. 请求格式：

/arcgis/rest/services/{folder}/{layer}/MapServer/wmts?SERVICE=WMTS&REQUEST=GetTile&VERSION=1.0.0&LAYER=imgmap&STYLE=default&TILEMATRIXSET=default028mm&TILEMATRIX={z}&TILEROW={y}&TILECOL={x}&FORMAT=image/png

前端mapboxgl示例代码：

        map.addLayer({
          id: "cgcs2000-img-layer",
          type: "raster",
          source: {
            type: "raster",
            tiles: [
              "http://localhost:3000/arcgis/rest/services/zj_tdt/services/wmts?SERVICE=WMTS&REQUEST=GetTile&VERSION=1.0.0&LAYER=imgmap&STYLE=default&TILEMATRIXSET=default028mm&TILEMATRIX={z}&TILEROW={y}&TILECOL={x}&FORMAT=image%2Fpng"
            ],
            tileSize: 256
          },
          paint: {},
          layout: { visibility: "visible" },
        });

Configuration

配置说明

• Modify the target_wmts_url variable in app.js to configure your WMTS service URL
• 修改app.js中的target_wmts_url变量配置您的WMTS服务地址
• Adjust the resolution parameters in the RESOLUTIONS array as needed
• 可根据需要调整RESOLUTIONS数组中的分辨率参数

开源协议

MIT License