Yeah, my python implemention isn’t completely same, so maybe not compareable … but I am wondering why loader.loadBamFile is so much faster (it takes 0.0 ms to load the same geometry), as it also generates geometry … maybe I can do it the same way? It is possible to pass a bunch of vertices to the GeomVertexWriters? Or change the write pointer?
Edit: I have already found this forum post: Faster way to build a mesh than GeomWriter ? and will give it a try … But is there a concrete example for modifying the data? I used
printf("'%s'", g_data->get_array(0)->get_handle()->get_data());and got ‘∟’ for ~500 vertices … which won’t help me much … also I am wondering in which format the data is stored in the string?
Thanks in advance, and sorry for so much questions 
Tobias