grf_use_colormap
err = grf_use_colormap(view, &cm);
int grf_use_colormap(view_t *v, colormap_t *cm);
&& (vu->view == NULL || grf_use_colormap(vu->view, cm)))
int grf_use_colormap(view_t *, colormap_t *);
&& (vu->view == NULL || grf_use_colormap(vu->view, cm)))