C++ How to delete the object have write in 3dm file?

Rhino Developer
1

Hi;
I write a mesh into 3dm file by this core:

static bool write( const wchar_t* file_path, int version, ON_Mesh mesh )
{
	if(mesh.IsValid())
	{
		ON::Begin();
		FILE* archive_fp = ON::OpenFile( file_path, L"wb");
		ON_BinaryFile archive( ON::write3dm, archive_fp );
		ON_WriteOneObjectArchive( archive, version, mesh );
		ON::CloseFile(archive_fp);
		ON::End();
	}
    return 1;
}

After I read the file and get the mesh, how cant I delete the object data have write?

2

Hi @pythonuser,

I am confused as to what you want to do? Do you want to write an empty 3dm file?

– Dale

3

Hi @dale,
I just want to update it, if I do not it, an then write a new object in, will the file be bigger and bigger?

4

Hi @pythonuser,

openNURBS offers no option for updating an existing file. If you want to modify a 3dm file, you will need to re-write it.

– Dale

5

Hi@ dale;
Got it, think you.