+static void
+pick_new_molecule (ModeInfo *mi, time_t last)
+{
+ molecule_configuration *mc = &mcs[MI_SCREEN(mi)];
+
+ if (mc->nmolecules == 1)
+ {
+ if (last != 0) return;
+ mc->which = 0;
+ }
+ else if (last == 0)
+ {
+ mc->which = random() % mc->nmolecules;
+ }
+ else
+ {
+ int n = mc->which;
+ while (n == mc->which)
+ n = random() % mc->nmolecules;
+ mc->which = n;
+ }
+
+ glNewList (mc->molecule_dlist, GL_COMPILE);
+ ensure_bounding_box_visible (mi);
+
+ do_labels = orig_do_labels;
+ do_bonds = orig_do_bonds;
+ MI_IS_WIREFRAME(mi) = orig_wire;
+
+ if (mc->molecule_size > mc->no_label_threshold)
+ do_labels = 0;
+ if (mc->molecule_size > mc->wireframe_threshold)
+ MI_IS_WIREFRAME(mi) = 1;
+
+ if (MI_IS_WIREFRAME(mi))
+ do_bonds = 1;
+
+ build_molecule (mi);
+ glEndList();
+}
+
+