// From   fan_monotonify_plazas_smart, case oshape = 3:    

      // Connect outer dents in zigzag fashion:
      #local kvoa0 = kvo_ini + 1 + km*Nvh;
      #local kvob0 = kvo_ini + Neo/2 - 4 + km*Nvh;
      #local kvoc0 = kvoa0 + 2;
      #local kvod0 = kvob0 + 2;
      fan_partition_zipper(V, kvoa0,kvob0,+2,  kvoc0,kvod0,+2, D,nd)
      
      #local kvoa1 = kvo_fin - 1 + km*Nvh;
      #local kvob1 = kvo_fin - Neo/2 + 4 + km*Nvh;
      #local kvoc1 = kvoa1 - 2;
      #local kvod1 = kvob1 - 2;
      fan_partition_zipper(V, kvoa1,kvob1,-2,  kvoc1,kvod1,-2, D,nd)
      
      // Connect second, next-to-last, and middle outer vertices to 
      // the first, last, and middle inner vertices:
      #local kvoi = kvo_ini + 1 + km*Nvh;
      #local kvii = kvi_ini + km*Nvh;
      fan_partition_one(V, kvoi,kvii, D,nd)
      
      #local kvom = kvo_mid + km*Nvh;
      #local kvim = kvi_mid + km*Nvh;
      fan_partition_one(V, kvom,kvim, D,nd)
      
      #local kvof = kvo_fin - 1 + km*Nvh;
      #local kvif = kvi_fin + km*Nvh;
      fan_partition_one(V, kvof,kvif, D,nd)