objects: Use a vtable to shrink object structs.

1 files changed, 7 insertions, 2 deletions

diff --git a/libdimension/cube.c b/libdimension/cube.c
index 8a1a503..d4c9d5b 100644
--- a/libdimension/cube.c
+++ b/libdimension/cube.c
@@ -129,13 +129,18 @@ dmnsn_cube_inside_fn(const dmnsn_object *cube, dmnsn_vector point)
       && point.z > -1.0 && point.z < 1.0;
 }
 
+/** Cube vtable. */
+static const dmnsn_object_vtable dmnsn_cube_vtable = {
+  .intersection_fn = dmnsn_cube_intersection_fn,
+  .inside_fn = dmnsn_cube_inside_fn,
+};
+
 /* Allocate a new cube object */
 dmnsn_object *
 dmnsn_new_cube(dmnsn_pool *pool)
 {
   dmnsn_object *cube = dmnsn_new_object(pool);
-  cube->intersection_fn = dmnsn_cube_intersection_fn;
-  cube->inside_fn = dmnsn_cube_inside_fn;
+  cube->vtable = &dmnsn_cube_vtable;
   cube->bounding_box.min = dmnsn_new_vector(-1.0, -1.0, -1.0);
   cube->bounding_box.max = dmnsn_new_vector(1.0, 1.0, 1.0);
   return cube;