Module vec3 

The crate’s shared 3-component vector math. Every module that needs a dot, cross, or component-wise op reaches for these rather than redeclaring them.

Normalisation deliberately stays with its caller: the degenerate-input rule differs by site (a fallback axis vs None vs a clamped length), and folding those together would change behavior at grazing inputs.

Functions

add

Component-wise sum, a + b.

cross

Cross product.

dot

Dot product.

length

Euclidean length.

lerp

Component-wise linear interpolation from a to b.

scale

Every component scaled by s.

sub

Component-wise difference, a - b.

vec3_add

Accumulate src into dst in place. Used by the smooth-normal passes, which sum every incident face normal per vertex before normalising once.

vec3_face_normal

Newell-style face normal from three CCW positions. Shared with the cook generators’ smooth-normal pass.

vec3_normalise

Unit-length n, falling back to +Y when it is too short to have a direction.