获取TIN坡度值 获取等高线 三维环境 过ISurface接口的GetContour方法-Get TIN slope values ​ ​ for three-dimensional environment contour interface GetContour way too ISurface

基于VC6+AE开发的3D源代码(其中属性查询、可视分析、坡向分析等、剖面绘制、等高线） -Developed based on VC6+ AE 3D source code (which attribute query, visual analysis, slope analysis, profile drawing, contour)

用VB.NET调用地理绘图软件Surfer的接口实现提取边缘，并绘制等值线图、矢量图、阴影地形图、维表面图-VB.NET using geographic mapping software called Surfer extract the edge of the interface and mapping contour map, vector, shaded relief map, map-dimensional surface

Guideline to calculate contour