Translate RAS coordinates, as used in volumes by applying vox2ras, to surface RAS.

Translate RAS coordinates, as used in volumes by applying vox2ras, to surface RAS.

Usage

ras.to.surfaceras(header_cras, ras_coords, first_voxel_RAS = c(1, 1, 1))

Arguments

header_cras

an MGH header instance from which to extract the cras (center RAS), or the cras vector, i.e., a numerical vector of length 3

ras_coords

nx3 numerical vector, the input surface RAS coordinates. Could be the vertex coordinates of an 'fs.surface' instance, or the RAS coords from a surface label.

first_voxel_RAS

the RAS of the first voxel, see mghheader.centervoxelRAS.from.firstvoxelRAS for details. Ignored if 'header_cras' is a vector.

Value

the surface RAS coords for the input RAS coords

Note

The RAS can be computed from Surface RAS by adding the center RAS coordinates, i.e., it is nothing but a translation.