v3_muladds( mtx[3], player->rb.v, k_rb_delta*substep, mtx[3] );
debug_capsule( mtx, w->collider.radius, w->collider.height, VG__YELOW );
v3_muladds( mtx[3], player->rb.v, k_rb_delta*substep, mtx[3] );
debug_capsule( mtx, w->collider.radius, w->collider.height, VG__YELOW );