potree-sdk/src/loader/ShapefileLoader.js

import * as THREE from "../../libs/three.js/build/three.module.js";
import {Line2} from "../../libs/three.js/lines/Line2.js";
import {LineGeometry} from "../../libs/three.js/lines/LineGeometry.js";
import {LineMaterial} from "../../libs/three.js/lines/LineMaterial.js";

import {LineDraw} from "../custom/utils/DrawUtil.js"; 

 
/*  proj4.defs("CGCS2000","+proj=tmerc +lat_0=0 +lon_0=114 +k=1 +x_0=500000 +y_0=0 +ellps=WGS84 +units=m +no_defs")
 
function transformCGCS2000ToWGS84([lng, lat]) {  
  // Define the CGCS2000 and WGS84 coordinate systems   
    const transformed = proj4("CGCS2000", "LOCAL", [lng, lat]);  
    return  transformed 
}  
 */


export class ShapefileLoader{

	constructor(){
		//this.transform = null;
	}

	async load(path, color){

		const matLine = new LineMaterial( {
			color: color || 0xff0000,
			lineWidth: 3, // in pixels
			resolution:  new THREE.Vector2(1000, 1000),
			dashed: false
		} );

 

		const features = await this.loadShapefileFeatures(path);
        if(!features){
            console.error('no features', path)
            return  
        }
        const node = new THREE.Object3D();
        
         
        let transform = await this.loadProj(path, node); 
        if(!transform){ 
            transform = this.analyseTransform(features, path, node ) //自己根据数字来猜测，经纬度一般能准，但数字很大的话就不对了。用户自己移动吧
        } 
         
        
        let jump = 0 
		for(const feature of features){//5是碎的
            //if(feature.geometry.type!= 'MultiLineString' || ++jump != 5) continue
			const fnode = this.featureToSceneNode(feature, matLine, transform);
			fnode && node.add(fnode);
		} 

		let setResolution = (x, y) => {
			matLine.resolution.set(x, y);
		};

		const result = {
			features: features,
			node: node,
			setResolution: setResolution,
		};

		return result;
	}





        


	featureToSceneNode(feature, matLine, transform){
        //console.log(feature)
        
		let geometry = feature.geometry;
		
		let color = new THREE.Color(1, 1, 1);

	 
		if(!transform){
			transform = (v)=> v //{forward: (v) => v};
		}
		
		if(geometry.type === "Point"){
			let sg = new THREE.SphereGeometry(1, 18, 18);
			let sm = new THREE.MeshNormalMaterial();
			let s = new THREE.Mesh(sg, sm);
			
			let [long, lat] = geometry.coordinates;
			let pos = transform/* .forward */([long, lat]);
			
			s.position.set(...pos, 20);
			
			s.scale.set(10, 10, 10);
			
			return s;
		}else if(geometry.type === "LineString"){
			let coordinates = [];
			
			let min = new THREE.Vector3(Infinity, Infinity, Infinity);
			for(let i = 0; i < geometry.coordinates.length; i++){
				let [long, lat] = geometry.coordinates[i];
				let pos = transform/* .forward */([long, lat]);
				
				min.x = Math.min(min.x, pos[0]);
				min.y = Math.min(min.y, pos[1]);
				min.z = Math.min(min.z, 20);
				
				coordinates.push(...pos, 20);
				if(i > 0 && i < geometry.coordinates.length - 1){
					coordinates.push(...pos, 20);
				}
			}
			
			for(let i = 0; i < coordinates.length; i += 3){
				coordinates[i+0] -= min.x;
				coordinates[i+1] -= min.y;
				coordinates[i+2] -= min.z;
			}
			
			const lineGeometry = new LineGeometry();
			lineGeometry.setPositions( coordinates );

			const line = new Line2( lineGeometry, matLine );
			line.computeLineDistances();
			line.scale.set( 1, 1, 1 );
			line.position.copy(min);
			
			return line;
		}else if(geometry.type === "MultiLineString"){//xzw add  江门的那个文件
			let coordinates = [];
			//console.warn('MultiLineString') //多组连续线段，组之间不连续
			let min = new THREE.Vector3(Infinity, Infinity, Infinity);
			for(let i = 0; i < geometry.coordinates.length; i++){ 
                let points = geometry.coordinates[i]; //有时候是两个点有时候多个
                let coordinateSlice = []
                points.forEach(point=>{
                    let [long, lat] = point;
                    let pos = transform/* .forward */([long, lat]);
                    min.x = Math.min(min.x, pos[0]);
                    min.y = Math.min(min.y, pos[1]);
                    min.z = Math.min(min.z, 20);
                    coordinateSlice.push(new THREE.Vector3(pos[0], pos[1], 20));
                }) 
                coordinates.push(coordinateSlice)        
			}
			 
            coordinates.forEach(coordinateSlice=> coordinateSlice.forEach(point=>point.sub(min) ))
                   
            let line = LineDraw.createFatLine(coordinates,{
                uncontinuous: true,
                mat:matLine
                /* color: 0xff0000,
                dashSize: 0.5, 
                gapSize: 0.2, 
                lineWidth: config$1.measure.lineWidth,  */
            });
            line.position.copy(min);
			
			return line;
		}else if(geometry.type === "Polygon"){
			for(let pc of geometry.coordinates){
				let coordinates = [];
				
				let min = new THREE.Vector3(Infinity, Infinity, Infinity);
				for(let i = 0; i < pc.length; i++){
					let [long, lat] = pc[i];
					let pos = transform/* .forward */([long, lat]);
					
					min.x = Math.min(min.x, pos[0]);
					min.y = Math.min(min.y, pos[1]);
					min.z = Math.min(min.z, 20);
					
					coordinates.push(...pos, 20);
					if(i > 0 && i < pc.length - 1){
						coordinates.push(...pos, 20);
					}
				}
				
				for(let i = 0; i < coordinates.length; i += 3){
					coordinates[i+0] -= min.x;
					coordinates[i+1] -= min.y;
					coordinates[i+2] -= min.z;
				}

				const lineGeometry = new LineGeometry();
				lineGeometry.setPositions( coordinates );

				const line = new Line2( lineGeometry, matLine );
				line.computeLineDistances();
				line.scale.set( 1, 1, 1 );
				line.position.copy(min);
				
				return line;
			}
		}else{
			console.log("unhandled feature: ",  geometry.type);
		}
        
        
        
        
        
        function getLine(coordinates){
            
        }
	} 

	async loadShapefileFeatures(file){
		let features = [];
        if(file.split('.').pop() == 'shp'){
            let source = await shapefile.open(file);
            
            while(true){
                let result = await source.read();

                if (result.done) {
                    break;
                }
                //value中的properties来自dbf，但该属性没有被用到，是否可以不加载
                if (result.value && result.value.type === 'Feature' && result.value.geometry !== undefined) {
                    features.push(result.value);
                }
            } 
            return features;
        }else if(file.split('.').pop() == 'json'){
            return new Promise((resolve,reject)=>{
                Potree.loadFile(file, { } , (data)=>{ 
                    console.log(data);
                    resolve(data.features) 
                });
            }) 
            
        }
		
	}
    
    
    
    
    analyseTransform(features, path, node){//xzw只能自己暂时判断下 ，最好能根据.prj判断
         
        if(viewer.transform){
            let count = 0, maxCount = 100
            let notLonLat, transform
            let prjJson = node.prjJson
            
            
            if(prjJson && prjJson.unit ){
                if(prjJson.unit.name.toLowerCase() == 'meter'   ){//'degree'
                    notLonLat = true  
                }
            }else{
                let judge = (coord)=>{
                    if(!(coord[0] >= -180 && coord[0] <= 180 && coord[1] >= -90 && coord[1] <=90 )){//如果超出经纬度范围，那就不是经纬度
                        notLonLat = true;   node.prjNotSure = true //不确定，不设定默认位置
                        
                    }
                    count++
                }//数字很小的话一般都是经纬度吧，就当作确定了
                
                for(let feature of features){ 
                    if(count > maxCount)break
                    for(let arr of feature.geometry.coordinates){
                        
                        if(arr[0] instanceof Array){
                            for(let coord of arr){
                                judge(coord)
                                if(count > maxCount || notLonLat)break
                            } 
                        }else{
                            judge(arr)
                            if(count > maxCount || notLonLat)break
                        }
                        
                        
                    } 
                } 
                  
            }
            if(notLonLat){
                /* transform = (v)=>{ 
                    let a = viewer.transform.lonlatTo4550.inverse(v)   //这种类型和不使用transform很接近
                    return viewer.transform.lonlatToLocal.forward(a)   
                } */   
                console.log('该shape不使用transform', path.split('/').pop())
            }else{
                transform = viewer.transform.lonlatToLocal.forward
                console.log('根据坐标数值猜测，该shape使用经纬度', path.split('/').pop())
            }
            return transform
            //loaders.shapeLoader.transform = viewer.transform.lonlatToLocal.forward;
        }else{
            node.prjNotSure = true 
            console.log('该shape没用任何transform 因为场景没有设置经纬度', path.split('/').pop() )
        }
    }

    
    
    
    
    async loadProj(path, model){
        let a = path.split('/') 
        let name = a.pop().split('.')[0]
        path = a.join('/') + '/' + name + '.prj';
        
          
         
        return new Promise((resolve,reject)=>{ 
            Potree.loadFile(path,{returnText:true},(e)=>{
                
                name += '_proj'
                let projDef = parsePrjToProj4(e, model) 
                proj4.defs(name, projDef)
                console.log('loadedProj:', name, '解析得def:  ',  projDef, '原：', e, 'json:', model.prjJson)
                
                try{
                    let proj = proj4(name, "LOCAL")
                    
                    let transform = ([lng, lat])=>{ 
                        return proj.forward([lng, lat]);  
                    }
                    resolve(transform)
                }catch(e){
                    console.warn(e,  '建立proj4 transform 失败', name ) 
                    resolve() 
                } 
                
            },()=>{
                resolve()  
            })
             
        })
        
        return  transform 
        
    }  
};




function parsePrjToProj4(prjString, model) {//将prj的内容变为proj4的transform
    
    let def = ''
    let json = model.prjJson = prjToJson(prjString)
     
    let projectionType
    let datum = '';
    let ellipsoid = '';
    let centralLon = '0', centralLat = '0';
    let scaleFactor = '1';
    let falseEasting = '0', falseNorthing = '0';
    
   
    
    
    
    if(json.projection == 'Transverse_Mercator'){
        projectionType = 'tmerc'
    }else if(!json.projection){
        projectionType = 'longlat'
    }else{
        projectionType = projection
        console.log('unknown projection:', json.projection)
    }
     
      
     
    if(json.parameters){
        falseEasting = json.parameters.false_easting
        falseNorthing = json.parameters.false_northing
        centralLon = json.parameters.central_meridian
        centralLat = json.parameters.latitude_of_origin
        scaleFactor = json.parameters.scale_factor 
    }
    
    if(json.geogcs?.spheroid){
        let spheroid = json.geogcs.spheroid.name.toLowerCase().replace('_', '')    
        if(spheroid.includes('wgs84') || spheroid.includes('wgs1984') )ellipsoid = 'WGS84'
    }
     
     
    def += `+proj=${projectionType} `
    def += `+lat_0=${centralLat} `;
    def += `+lon_0=${centralLon} `;
    def += `+k=${scaleFactor} `;
    def += `+x_0=${falseEasting} `;
    def += `+y_0=${falseNorthing} `;
    ellipsoid && (def += `+ellps=${ellipsoid} `);
    def += '+units=m +no_defs';
    return def
    
}






function prjToJson(prjString) {//将prj的内容变为json
    const result = {};

    // 提取 PROJCS 和 GEOGCS 信息
    const projcsMatch = prjString.match(/PROJCS\["([^"]+)",(.*)\]/);
    if (projcsMatch) {
        result.projcsName = projcsMatch[1];
        const geoPart = projcsMatch[2];
        
        // 解析 GEOGCS 部分
        const geoMatch = geoPart.match(/GEOGCS\["([^"]+)",DATUM\["([^"]+)",SPHEROID\["([^"]+)",([0-9.]+),([0-9.]+)\]\],PRIMEM\["([^"]+)",([0-9.]+)\],UNIT\["([^"]+)",([0-9.]+)\]/);
        if (geoMatch) {
            result.geogcs = {
                name: geoMatch[1],
                datum: geoMatch[2],
                spheroid: {
                    name: geoMatch[3],
                    semiMajorAxis: parseFloat(geoMatch[4]),
                    inverseFlattening: parseFloat(geoMatch[5])
                },
                primeMeridian: {
                    name: geoMatch[6],
                    value: parseFloat(geoMatch[7])
                },
                unit: {
                    name: geoMatch[8],
                    conversionFactor: parseFloat(geoMatch[9])
                }
            };
        }

        // 解析 PROJECTION 部分
        const projMatch = geoPart.match(/PROJECTION\["([^"]+)"\]/);
        if (projMatch) {
            result.projection = projMatch[1];
        }

        // 解析 PARAMETER 部分
        const parameters = {};
        const paramMatches = geoPart.matchAll(/PARAMETER\["([^"]+)",([-\d.]+)\]/g);
        for (const match of paramMatches) {
            parameters[match[1]] = parseFloat(match[2]);
        }
        result.parameters = parameters;

        // 解析 UNIT 部分
        const unitMatch = geoPart.match(/UNIT\["([^"]+)",([-\d.]+)\]/);
        if (unitMatch) {
            result.unit = {
                name: unitMatch[1],
                conversionFactor: parseFloat(unitMatch[2])
            };
        }
    } else {
        // 如果没有 PROJCS，则尝试解析 GEOGCS
        const geoMatch = prjString.match(/GEOGCS\["([^"]+)",DATUM\["([^"]+)",SPHEROID\["([^"]+)",([0-9.]+),([0-9.]+)\]\],PRIMEM\["([^"]+)",([0-9.]+)\],UNIT\["([^"]+)",([0-9.]+)\]/);
        if (geoMatch) {
            result.geogcs = {
                name: geoMatch[1],
                datum: geoMatch[2],
                spheroid: {
                    name: geoMatch[3],
                    semiMajorAxis: parseFloat(geoMatch[4]),
                    inverseFlattening: parseFloat(geoMatch[5])
                },
                primeMeridian: {
                    name: geoMatch[6],
                    value: parseFloat(geoMatch[7])
                },
                unit: {
                    name: geoMatch[8],
                    conversionFactor: parseFloat(geoMatch[9])
                }
            };
        }
    }

    return result;
}





/* 
  
function parsePrjToProj4(prjString) {
    // 初始化 Proj4 字符串的部分
    let proj4Def = ''

    // 提取关键信息
    const prjParts = prjString.match(/(\w+)\[(.*?)\]/g);
     
    let projectionType = '';
    let datum = '';
    let ellipsoid = '';
    let centralMeridian = '';
    let scaleFactor = '1';
    let falseEasting = '0';
    let falseNorthing = '0';
    let latitudeOfOrigin = '0';

    prjParts.forEach(part => {
        if (part.includes('PROJECTION')) {
            projectionType = part.match(/"([^"]+)"/)[1].toLowerCase().replace('_', ''); 
            //xzw:
            if(projectionType == 'transversemercator') projectionType = 'tmerc'
             
        }else if (part.includes('DATUM')) {
            datum = part.match(/"([^"]+)"/)[1];
        } else if (part.includes('SPHEROID')) {
            ellipsoid = part.match(/"([^"]+)"/)[1].toLowerCase();
        } else if (part.includes('PARAMETER')) {
            let paramName = part.match(/"([^"]+)"/)[1].toLowerCase().replace(/ /g, '_');
            let paramValue = part.match(/(-?\d+\.?\d*)/)[1];
            switch (paramName) {
                case 'central_meridian':
                    centralMeridian = paramValue;
                    break;
                case 'scale_factor':
                    scaleFactor = paramValue;
                    break;
                case 'false_easting':
                    falseEasting = paramValue;
                    break;
                case 'false_northing':
                    falseNorthing = paramValue;
                    break;
                case 'latitude_of_origin':
                    latitudeOfOrigin = paramValue;
                    break;
            }
        }
    });

    // 构建完整的 Proj4 定义字符串
    if(!projectionType && prjString.includes('GCS_WGS_1984')) projectionType = 'longlat'
    
    
    projectionType && (proj4Def += `+proj=${projectionType} `) 
    proj4Def += `+lat_0=${latitudeOfOrigin} `;
    proj4Def += `+lon_0=${centralMeridian} `;
    proj4Def += `+k=${scaleFactor} `;
    proj4Def += `+x_0=${falseEasting} `;
    proj4Def += `+y_0=${falseNorthing} `;
    ellipsoid && (proj4Def += `+ellps=${ellipsoid} `);
    proj4Def += '+units=m +no_defs';

    return proj4Def;
}
 */




 /* 
function parsePrjToProj4(prjString) {
    // 初始化 Proj4 参数对象
    let proj4Params = {};
    
    // 提取 PROJCS 和 GEOGCS 部分
    const projcsMatch = prjString.match(/PROJCS\["([^"]+)",(.*)\]/);
    if (projcsMatch){ 
    
    const projcsName = projcsMatch[1];
    const geoPart = projcsMatch[2];

    // 解析 GEOGCS 部分
    const datumMatch = geoPart.match(/DATUM\["([^"]+)",SPHEROID\["([^"]+)",([0-9.]+),([0-9.]+)\]\]/);
    if (datumMatch) {
        proj4Params.datum = datumMatch[1].toLowerCase();
        proj4Params.ellps = datumMatch[2].toLowerCase();
        proj4Params.a = parseFloat(datumMatch[3]); // Semi-major axis
        proj4Params.rf = parseFloat(datumMatch[4]); // Inverse flattening
    }

    // 解析 PROJECTION 部分
    const projMatch = geoPart.match(/PROJECTION\["([^"]+)"\]/);
    if (projMatch) {
        proj4Params.proj = projMatch[1].toLowerCase().replace(/_/g, '');
    }

    // 解析 PARAMETER 部分
    const paramMatches = geoPart.matchAll(/PARAMETER\["([^"]+)",([-\d.]+)\]/g);
    for (const match of paramMatches) {
        const paramName = match[1].toLowerCase().replace(/ /g, '_');
        const paramValue = parseFloat(match[2]);
        switch (paramName) {
            case 'false_easting':
                proj4Params.x_0 = paramValue;
                break;
            case 'false_northing':
                proj4Params.y_0 = paramValue;
                break;
            case 'central_meridian':
                proj4Params.lon_0 = paramValue;
                break;
            case 'scale_factor':
                proj4Params.k = paramValue;
                break;
            case 'latitude_of_origin':
                proj4Params.lat_0 = paramValue;
                break;
        }
    }

    // 设置单位
    proj4Params.units = "m"; // 默认米
    proj4Params.no_defs = true;

    // 构建 Proj4 字符串
    let proj4Def = '+proj=' + proj4Params.proj;
    proj4Def += ' +lat_0=' + proj4Params.lat_0;
    proj4Def += ' +lon_0=' + proj4Params.lon_0;
    proj4Def += ' +k=' + proj4Params.k;
    proj4Def += ' +x_0=' + proj4Params.x_0;
    proj4Def += ' +y_0=' + proj4Params.y_0;
    proj4Def += ' +ellps=' + proj4Params.ellps;
    proj4Def += ' +units=' + proj4Params.units;
    proj4Def += ' +no_defs';

    return proj4Def;
}
 */
  
//shp必须，dbf目前没用，prj最好有