Check if a Nonlinear Template Warp is Needed

Determines whether two template spaces are in the same coordinate system but on different template grids, requiring a nonlinear warp.

Usage

needs_template_warp(from, to)

Arguments

from

Source template space identifier.

to

Target template space identifier.

Value

Logical. `TRUE` if the templates share a coordinate space but differ in grid/registration, `FALSE` otherwise, `NA` if either space is unknown.

Details

This function identifies cases where an affine transform is NOT needed but a nonlinear warp IS needed. For example, MNI152NLin6Asym and MNI152NLin2009cAsym are both in MNI152 coordinate space but use different nonlinear registration targets, so voxel grids don't align exactly (~2mm difference).

See also

[needs_coord_transform()] for checking coordinate-space differences, [atlas_transform_plan()] for planning multi-step transforms.

Examples

needs_template_warp("MNI152NLin6Asym", "MNI152NLin2009cAsym")  # TRUE
#> [1] TRUE
needs_template_warp("fsaverage", "fsaverage6")                   # TRUE
#> [1] TRUE
needs_template_warp("fsaverage", "MNI152")                       # FALSE (different coord spaces)
#> [1] FALSE
needs_template_warp("MNI152NLin6Asym", "MNI152NLin6Asym")       # FALSE (identical)
#> [1] FALSE