Function box_transform 

pub fn box_transform(
    rect: Rect,
    rotate_deg: f32,
    scale_x: f32,
    scale_y: f32,
    translate_x: f32,
    translate_y: f32,
) -> Option<[f32; 6]>

Builds the affine matrix for a box’s declarative rotate/scale/translate attributes, pivoting rotation and scale on the box centre. Returns None when every component is identity, so an untransformed box skips the extra transform node entirely.