/* ** makestreet.c Copyright 1991 Kent Paul Dolan, ** Mountain View, CA, USA 94039-0755 ** ** Written to satisfy an inquiry on USENet's rec.games.programmer newsgroup. ** May be freely used or modified in any non-commercial work. Copyrighted ** only to prevent patenting by someone else. */ #include #include "townmaze.h" #include "townproto.h" #ifdef __STDC__ int makestreet(int chosencell,int streetid,int streetpoints) #else int makestreet(chosencell,streetid,streetpoints) int chosencell,streetid, streetpoints; #endif { int choseni, chosenj; int nhbrid, nextnhbrid, thirdnhbrid; int streetwalk, highstreetnum, lowstreetnum; int canstraighten; /* ** Check that a street isn't going in next to an unused cell; if it is, ** mark it dead, instead if it's live; in any case, refuse to do it. */ for (nhbrid = 0; nhbrid < 4; nhbrid++) { if (nhbrexists(chosencell,nhbrid)) if (statlist[nhbris(chosencell,nhbrid)].status == UNUSED) { if (statlist[chosencell].status == LIVE) movefromto(&live,&livect,&dead,&deadct,DEAD,chosencell); return(1==0); } } /* ** Check for and abide by straightness control */ if ((mazestraightness > 0) && (streetpoints == -1)) if ((RANDOM()%1000) < mazestraightness) { canstraighten = (1==0); for (nhbrid = 0; nhbrid < 4; nhbrid++) if (nhbrexists(chosencell,nhbrid)) if (statlist[nhbris(chosencell,nhbrid)].streetdir == ((nhbrid+2)%4)) canstraighten = (1==1); if (!canstraighten) return(1==0); } /* ** Update the chosen cell in the status list */ switch (statlist[chosencell].status) { case UNUSED: case STREET: fprintf(stderr,"error picking street; bad cell status %d\n", statlist[chosencell].status); freespace(); exit(1); break; case LIVE: /* fprintf(stderr,"moving cell %d from live to street\n",chosencell); */ movefromto(&live,&livect,&street,&streetct,STREET,chosencell); break; case DEAD: /* fprintf(stderr,"moving cell %d from dead to street\n",chosencell); */ movefromto(&dead,&deadct,&street,&streetct,STREET,chosencell); break; case ISOLATED: /* fprintf(stderr,"moving cell %d from isolated to street\n",chosencell);*/ movefromto(&isolated,&isolatedct,&street,&streetct,STREET,chosencell); break; default: fprintf(stderr,"unexpected chosencell status in makegates %d\n", statlist[chosencell].status); } /* ** Give the street the required streetid, either new or continuing an ** existing street. */ statlist[chosencell].streetnum = streetid; /* ** Update the chosen cell on the map. */ choseni = chosencell / (mazewidth/2); chosenj = chosencell % (mazewidth/2); choseni = 2 * choseni + 1; chosenj = 2 * chosenj + 1; cmaze[choseni - 1][chosenj] = HDOOR; cmaze[choseni][chosenj + 1] = VDOOR; cmaze[choseni + 1][chosenj] = HDOOR; cmaze[choseni][chosenj - 1] = VDOOR; /* ** Update the neighbors of the new street cell; */ for (nhbrid = 0; nhbrid < 4; nhbrid++) { if (nhbrexists(chosencell,nhbrid)) switch (statlist[nhbris(chosencell,nhbrid)].status) { case UNUSED: fprintf(stderr, "logic error; tried to put a street beside an unused cell\n"); showdebugmaze(); freespace(); exit(1); break; case STREET: switch (nhbrid) /* change the door to a passage, adopt a continuing */ { /* direction from a neighbor street */ case 0: cmaze[choseni - 1][chosenj] = BLANK; if (statlist[nhbris(chosencell,nhbrid)].streetdir == 2) statlist[chosencell].streetdir = 2; break; case 1: cmaze[choseni][chosenj + 1] = BLANK; if (statlist[nhbris(chosencell,nhbrid)].streetdir == 3) statlist[chosencell].streetdir = 3; break; case 2: cmaze[choseni + 1][chosenj] = BLANK; if (statlist[nhbris(chosencell,nhbrid)].streetdir == 0) statlist[chosencell].streetdir = 0; break; case 3: cmaze[choseni][chosenj - 1] = BLANK; if (statlist[nhbris(chosencell,nhbrid)].streetdir == 1) statlist[chosencell].streetdir = 1; break; default: fprintf(stderr,"bad nhbrid in nhbr update street switch case\n"); /* The above should be impossible; nhbrexists and nhbris already */ /* both checked for this problem */ showdebugmaze(); freespace(); exit(1); } if (statlist[chosencell].streetnum != statlist[nhbris(chosencell,nhbrid)].streetnum) { /* ** Two different streets have met; merge their streetids and decrement the ** streetcount. */ lowstreetnum = ( ( statlist[chosencell].streetnum > statlist[nhbris(chosencell,nhbrid)].streetnum ) ? statlist[nhbris(chosencell,nhbrid)].streetnum : statlist[chosencell].streetnum ); highstreetnum = ( ( statlist[chosencell].streetnum < statlist[nhbris(chosencell,nhbrid)].streetnum ) ? statlist[nhbris(chosencell,nhbrid)].streetnum : statlist[chosencell].streetnum ); streetwalk = street; while (streetwalk != NOPOINTER) { if (statlist[streetwalk].streetnum == highstreetnum) statlist[streetwalk].streetnum = lowstreetnum; streetwalk = statlist[streetwalk].next; } streetnumct--; } break; case DEAD: /* do nothing; that's why it's called dead */ break; case LIVE: movefromto(&live,&livect,&dead,&deadct,DEAD,nhbris(chosencell,nhbrid)); for (nextnhbrid = 0; nextnhbrid < 4; nextnhbrid++) if (nhbrexists(nhbris(chosencell,nhbrid),nextnhbrid)) if (statlist[nhbris(nhbris(chosencell,nhbrid),nextnhbrid)].status == ISOLATED) { movefromto(&dead,&deadct,&live,&livect,LIVE, nhbris(chosencell,nhbrid)); break; } break; case ISOLATED: movefromto(&isolated,&isolatedct,&dead,&deadct,DEAD, nhbris(chosencell,nhbrid)); statlist[nhbris(chosencell,nhbrid)].status = DEAD; /* ** Only let an isolated cell become live if it is interior; stops ** streets from running along the city wall, creating lots of gates. ** Don't make it live if it is next to an unused cell, either, since ** it can never become a street cell. */ if ( interiorcell(nhbris(chosencell,nhbrid)) && (statlist[nhbris(nhbris(chosencell,nhbrid),0)].status != UNUSED) && (statlist[nhbris(nhbris(chosencell,nhbrid),1)].status != UNUSED) && (statlist[nhbris(nhbris(chosencell,nhbrid),2)].status != UNUSED) && (statlist[nhbris(nhbris(chosencell,nhbrid),3)].status != UNUSED) ) for (nextnhbrid = 0; nextnhbrid < 4; nextnhbrid++) if (nhbrexists(nhbris(chosencell,nhbrid),nextnhbrid)) if (statlist[nhbris(nhbris(chosencell,nhbrid),nextnhbrid)].status == ISOLATED) { movefromto(&dead,&deadct,&live,&livect,LIVE, nhbris(chosencell,nhbrid)); break; } /* ** When an isolated cell stops being so, neighbors may stop being live ** that were depending on it for that status; we're not done! */ for (nextnhbrid = 0; nextnhbrid < 4; nextnhbrid++) if (nhbrexists(nhbris(chosencell,nhbrid),nextnhbrid)) if (statlist[nhbris(nhbris(chosencell,nhbrid),nextnhbrid)].status == LIVE) { movefromto(&live,&livect,&dead,&deadct,DEAD, nhbris(nhbris(chosencell,nhbrid),nextnhbrid)); for (thirdnhbrid =0; thirdnhbrid <4; thirdnhbrid++) { if (nhbrexists(nhbris(nhbris(chosencell, nhbrid), nextnhbrid), thirdnhbrid)) if (statlist[nhbris(nhbris(nhbris(chosencell, nhbrid), nextnhbrid), thirdnhbrid)].status == ISOLATED) { movefromto(&dead,&deadct,&live,&livect,LIVE, nhbris(nhbris(chosencell,nhbrid),nextnhbrid)); break; } } } break; default: fprintf(stderr,"bad statlist[%d].status entry %d\n", nhbris(chosencell,nhbrid), statlist[nhbris(chosencell,nhbrid)].status); showdebugmaze(); freespace(); exit(1); } } if (statlist[chosencell].streetdir == -1) if (streetpoints != -1) statlist[chosencell].streetdir = streetpoints; else { for (nhbrid = 0; nhbrid < 4; nhbrid++) { if (nhbrexists(chosencell,nhbrid)) if (statlist[nhbris(chosencell,nhbrid)].status == STREET) { statlist[chosencell].streetdir = ((nhbrid +2)%4); break; } } } /* showdebugmaze(); */ return(1==1); }