learning js and some demos
js+geometry
试验troika-three-text
learn c++
测试开源库：https://github.com/DomCR/ACadSharp
测试C#开源库：https://github.com/ixmilia/dxf 开源库NuGet地址：https://www.nuget.org/packages/IxMilia.Dxf 包含内容：关于dxf和dxb的读写与转换
