}
void
-xr_rendering_measure (struct xr_rendering *r, int *wp, int *hp)
+xr_rendering_measure (const struct xr_rendering *r, int *wp, int *hp)
{
int w, h;
void xr_rendering_destroy (struct xr_rendering *);
void xr_rendering_apply_options (struct xr_rendering *, struct string_map *o);
-void xr_rendering_measure (struct xr_rendering *, int *w, int *h);
+void xr_rendering_measure (const struct xr_rendering *, int *w, int *h);
void xr_rendering_draw (struct xr_rendering *r, cairo_t *cr,
int x0, int y0, int x1, int y1);