| indices | 定义网格的索引的数组。 |
| topology | 网格的拓扑，例如：三角形、线条、四边形、点等。请参阅 MeshTopology。 |
| submesh | The submesh to modify. |
| calculateBounds | 在设置索引之后计算网格的包围盒。这会在默认情况下进行。 在要使用现有包围盒并减少设置索引的 CPU 开销时，请使用 false。 |
| baseVertex | 添加到所有三角形顶点索引的可选顶点偏移。 |
Sets the index buffer for the sub-Mesh.
A sub-Mesh is simply a separate indices array. When the Mesh Renderer uses multiple Materials, you should
ensure that there are as many sub-Meshes as Materials.
SetTriangles 和 triangles 始终将网格设置为由三角形的面
组成。使用 SetIndices 可创建由线条或点组成的网格。
The baseVertex argument can be used to achieve meshes that are larger than 65535 vertices while using 16 bit index buffers,
as long as each submesh fits within its own 65535 vertex area. For example, if the index buffer that is passed to SetIndices
contains indices 10,11,12 and baseVertex is set to 100000, then effectively vertices 100010, 100011 and 100012 will be
used for rendering.
另请参阅：subMeshCount、MeshTopology 枚举、indexFormat。