Article Outline
近期在工作中有涉及一个水深自动化上图的工作，将海图的dwg文件提取水深点生成水深热力图，是以做此纪录，以便查阅与分享。
环境与软件
需要有arcgis的环境，geoserver，详细部署请参考网络。
处理流程
提取点要素
将dwg文件中点要素提取出来并且通过查询语句过滤，保存成shape以便后续使用，若对shp文件成果无需求的可直接提取featureclass进行后续处理，这是一个通用cad转shp的方法。
public void CadToShapeFile(string filepath , string type , string outputpath , string whereClause) {
if (!File.Exists(filepath) && System.IO.Path.GetExtension(filepath) != ".dwg") {
return;
}
string fileDirectory = System.IO.Path.GetDirectoryName(filepath);
string fileName = System.IO.Path.GetFileName(filepath);
//打开cad获取要素
IWorkspaceFactory pWF = new CadWorkspaceFactory();
IWorkspace pW = pWF.OpenFromFile(fileDirectory, 0);
IFeatureWorkspace pFW = (IFeatureWorkspace)pW;
IFeatureClass pFeatureClass = pFW.OpenFeatureClass(fileName+":"+type);
string outputDirectory = System.IO.Path.GetDirectoryName(outputpath);
string outputName = System.IO.Path.GetFileNameWithoutExtension(outputpath);
//打开shapefile文件夹
IWorkspaceFactory pWSF = new ShapefileWorkspaceFactoryClass();
IWorkspace pOutWorkspace = pWSF.OpenFromFile(outputDirectory, 0);
IDataset pOutDataSet = pOutWorkspace as IDataset;
IWorkspaceName pOutWorkspaceName = pOutDataSet.FullName as IWorkspaceName;
//用cad的featureclass
IDataset pInDataSet = pFeatureClass as IDataset;
IFeatureClassName pInFeatureClassName = pInDataSet.FullName as IFeatureClassName;
IFeatureClassName pOutFeatureClassName = new FeatureClassNameClass();
IDatasetName pOutDataSetName = pOutFeatureClassName as IDatasetName;
pOutDataSetName.WorkspaceName = pOutWorkspaceName;
pOutDataSetName.Name = outputName;
IQueryFilter pInQueryFilter = new QueryFilterClass()
{
WhereClause = whereClause,
};
IFields pOutFields = null;
IEnumFieldError enumFieldError = null;
IFields fields = pFeatureClass.Fields;
IFieldChecker fieldChecker = new FieldCheckerClass();
IWorkspace pInWorkspace = pInDataSet.Workspace;
fieldChecker.InputWorkspace = pInWorkspace;
fieldChecker.ValidateWorkspace = pOutWorkspace;
fieldChecker.Validate(fields, out enumFieldError, out pOutFields);
IFeatureDataConverter featureDataConverter = new FeatureDataConverterClass();
featureDataConverter.ConvertFeatureClass(pInFeatureClassName, pInQueryFilter, null, pOutFeatureClassName, null, pOutFields, "", 100, 0);
System.Runtime.InteropServices.Marshal.ReleaseComObject(featureDataConverter);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pOutWorkspace);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pFeatureClass);
System.Runtime.InteropServices.Marshal.ReleaseComObject(pW);
}生成tin
通过提取出来的带高程值的点生成tin文件，并且通过约束三角网周长来使其外轮廓更贴近于点集的外包多边形。
IGeoDataset pGeoDataset = pFeatureClass as IGeoDataset;
ITinEdit pTinEdit = new TinClass();
pTinEdit.InitNew(pGeoDataset.Extent);
object pObj = Type.Missing;
//将点集作为约束点
pTinEdit.AddFromFeatureClass(pFeatureClass, null, pField, null,
esriTinSurfaceType.esriTinMassPoint, ref pObj);
pTinEdit.SaveAs(pPath, ref pObj);
pTinEdit.Refresh();
ITin pTin = pTinEdit as ITin;
//约束三角网周长
new Geoprocessor { OverwriteOutput = true, }.Execute(new DelineateTinDataArea { in_tin = pTin, max_edge_length = length, }, null);
return pTinEdit as ITin;生成栅格数据
通过GP将tin生成栅格数据。
Geoprocessor gp = new Geoprocessor();
gp.OverwriteOutput = true;
TinRaster tinRaster = new TinRaster();
tinRaster.in_tin = tin;
tinRaster.out_raster = path;
tinRaster.data_type = "FLOAT";
tinRaster.method = "LINEAR";
tinRaster.sample_distance = "CELLSIZE " + pixelSize;
tinRaster.z_factor = 1;
gp.Execute(tinRaster, null);服务配置发布
通过geoserver rest api来注册tif数据源和发布图层。
//注册数据源
this.$axios({
method:"post",
url: geoserver.url + "workspaces/{workspace}/coveragestores",
headers: {Authorization : geoserver.auth},
data:{}
})//注册图层
this.$axios({
method:"post",
url: geoserver.url + "workspaces/{workspace}/coveragestores/{coveragestores}/coverages",
headers: {Authorization : geoserver.auth},
data:{}
})服务调用
前端使用cesium调用wms服务，并且可以通过sld_body来更改样式。
let imageryProvider = new Cesium.WebMapServiceImageryProvider(param)
this.wmsLayer = window.app.viewer.imageryLayers.addImageryProvider(imageryProvider)通过最大最小值和色带分类动态赋值，此处采用等间距的分类方法
getStyle(layer,min,max,classes){
let colorMapEntry = "";
let interval = (max-min)/classes
for(let i = 0 ; i < classes ; i++){
let quantity = min + i*interval;
colorMapEntry = colorMapEntry + `<ColorMapEntry color="${colorRamp[i]}" quantity="${quantity}"/>`
}
const sld = `<?xml version="1.0" encoding="UTF-8"?>
<StyledLayerDescriptor version="1.0.0" xmlns="http://www.opengis.net/sld" xmlns:ogc="http://www.opengis.net/ogc"
xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.opengis.net/sld http://schemas.opengis.net/sld/1.0.0/StyledLayerDescriptor.xsd">
<NamedLayer>
<Name>${layer}</Name>
<UserStyle>
<Name>style</Name>
<Title>NDVI distribution</Title>
<FeatureTypeStyle>
<Rule>
<RasterSymbolizer>
<Opacity>1.0</Opacity>
<ColorMap>
${colorMapEntry}
</ColorMap>
</RasterSymbolizer>
</Rule>
</FeatureTypeStyle>
</UserStyle>
</NamedLayer>
</StyledLayerDescriptor>`
return sld;
},
结尾
参考： https://blog.csdn.net/giser_whu/article/details/25747279 https://blog.csdn.net/RicardoMTan/article/details/106213973 若有参考到的没赋链接的请告知本人，本人注明或做出修改，万分抱歉。 若需转载请注明本文链接，感谢观看。