opencascade example

OpenCascade 是一个开源的三维造型软件开发工具包，用于提供三维造型相关的函数库。

下面是一个 OpenCascade 的简单示例：

#include <BRepPrimAPI_MakeBox.hxx>
#include <BRepAlgoAPI_Cut.hxx>
#include <TopoDS_Shape.hxx>
#include <TopoDS_Solid.hxx>
#include <TopoDS_Compound.hxx>
#include <BRep_Builder.hxx>
#include <gp_Pnt.hxx>

int main(int argc, char *argv[])
{
  TopoDS_Solid box = BRepPrimAPI_MakeBox(100., 100., 100.);
  TopoDS_Solid sphere = BRepPrimAPI_MakeSphere(gp_Pnt(0, 0, 0), 50);
  TopoDS_Compound compound;
  BRep_Builder builder;
  builder.MakeCompound(compound);
  builder.Add(compound, box);
  builder.Add(compound, sphere);
  TopoDS_Shape result = BRepAlgoAPI_Cut(compound, sphere);
  return 0;
}

这段代码会创建一个长方体和一个球体，然后用球体对长方体进行求差操作，得到最终的造型。