Dear MNE group,
Sorry to bother people during the Christmas and New Year break. I have a question about how to load the surface files in order to analyse triangulation information.
I use the mne_read_surfaces function in Matlab to load the surface information of the whole brain. As stated in the manual, it returns a structure with a field .tris, which indicates "vertex numbers of triangles in counter clockwise order as seen from outside". To valid if the vertices in each raw of this field are indeed forming a tiny triangle, I visualise them using mne_analyse with the same surface loaded.
Then, I performed a series of test by typing some random raws of the field of .tris in the bottom part of the GUI where it says "vertex # :". A tiny red cross appears on the surface marking out where the vertex is. I marked out all three vertices from the same raw of .tris. However, I was very surprised to see that these red crosses are way apart from each other and not forming a triangular shape!
I am not sure if I misunderstand what this triangulation information really means, or there is anything else I did wrong.
Many thanks for your answer and helps!
Li Su