--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xrogue/passages.c	Tue Apr 21 08:55:20 2015 -0400
@@ -0,0 +1,370 @@
+/*
+    passages.c - Draw the connecting passages
+    
+    XRogue: Expeditions into the Dungeons of Doom
+    Copyright (C) 1991 Robert Pietkivitch
+    All rights reserved.
+    
+    Based on "Advanced Rogue"
+    Copyright (C) 1984, 1985 Michael Morgan, Ken Dalka and AT&T
+    All rights reserved.
+
+    Based on "Rogue: Exploring the Dungeons of Doom"
+    Copyright (C) 1980, 1981 Michael Toy, Ken Arnold and Glenn Wichman
+    All rights reserved.
+    
+    See the file LICENSE.TXT for full copyright and licensing information.
+*/
+
+#include <curses.h>
+#include "rogue.h"
+
+/*
+ * do_passages:
+ *      Draw all the passages on a level.
+ */
+
+do_passages()
+{
+    register struct rdes *r1, *r2 = NULL;
+    register int i, j;
+    register int roomcount;
+    static struct rdes
+    {
+        bool    conn[MAXROOMS];         /* possible to connect to room i? */
+        bool    isconn[MAXROOMS];       /* connection been made to room i? */
+        bool    ingraph;                /* this room in graph already? */
+    } rdes[MAXROOMS] = {
+        { { 0, 1, 0, 1, 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 1, 0, 1, 0, 1, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 0, 1, 0, 0, 0, 1, 0, 0, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 1, 0, 0, 0, 1, 0, 1, 0, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 0, 1, 0, 1, 0, 1, 0, 1, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 0, 0, 1, 0, 1, 0, 0, 0, 1 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 0, 0, 0, 1, 0, 0, 0, 1, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 0, 0, 0, 0, 1, 0, 1, 0, 1 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+        { { 0, 0, 0, 0, 0, 1, 0, 1, 0 }, { 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 0 },
+    };
+
+    /*
+     * reinitialize room graph description
+     */
+    for (i = 0; i < MAXROOMS; i++)
+    {
+        r1 = &rdes[i];
+        for (j = 0; j < MAXROOMS; j++)
+            r1->isconn[j] = FALSE;
+        r1->ingraph = FALSE;
+    }
+
+    /*
+     * starting with one room, connect it to a random adjacent room and
+     * then pick a new room to start with.
+     */
+    roomcount = 1;
+    r1 = &rdes[rnd(MAXROOMS)];
+    r1->ingraph = TRUE;
+    do
+    {
+        /*
+         * find a room to connect with
+         */
+        j = 0;
+        for (i = 0; i < MAXROOMS; i++)
+            if (r1->conn[i] && !rdes[i].ingraph && rnd(++j) == 0)
+                r2 = &rdes[i];
+        /*
+         * if no adjacent rooms are outside the graph, pick a new room
+         * to look from
+         */
+        if (j == 0)
+        {
+            do
+                r1 = &rdes[rnd(MAXROOMS)];
+            until (r1->ingraph);
+        }
+        /*
+         * otherwise, connect new room to the graph, and draw a tunnel
+         * to it
+         */
+        else
+        {
+            r2->ingraph = TRUE;
+            i = r1 - rdes;
+            j = r2 - rdes;
+            conn(i, j);
+            r1->isconn[j] = TRUE;
+            r2->isconn[i] = TRUE;
+            roomcount++;
+        }
+    } while (roomcount < MAXROOMS);
+
+    /*
+     * attempt to add passages to the graph a random number of times so
+     * that there isn't just one unique passage through it.
+     */
+    for (roomcount = rnd(5); roomcount > 0; roomcount--)
+    {
+        r1 = &rdes[rnd(MAXROOMS)];      /* a random room to look from */
+        /*
+         * find an adjacent room not already connected
+         */
+        j = 0;
+        for (i = 0; i < MAXROOMS; i++)
+            if (r1->conn[i] && !r1->isconn[i] && rnd(++j) == 0)
+                r2 = &rdes[i];
+        /*
+         * if there is one, connect it and look for the next added
+         * passage
+         */
+        if (j != 0)
+        {
+            i = r1 - rdes;
+            j = r2 - rdes;
+            conn(i, j);
+            r1->isconn[j] = TRUE;
+            r2->isconn[i] = TRUE;
+        }
+    }
+}
+
+/*
+ * conn:
+ *      Draw a corridor from a room in a certain direction.
+ */
+
+conn(r1, r2)
+int r1, r2;
+{
+    register struct room *rpf, *rpt = NULL;
+    register char rmt;
+    register int distance = 0, max_diag, offset = 0, i;
+    register int rm;
+    int turns[3], turn_dist[3];
+    register char direc;
+	coord delta = {0, 0}, curr, turn_delta = {0,0}, spos = {0,0}, epos = {0,0};
+
+    if (r1 < r2)
+    {
+        rm = r1;
+        if (r1 + 1 == r2)
+            direc = 'r';
+        else
+            direc = 'd';
+    }
+    else
+    {
+        rm = r2;
+        if (r2 + 1 == r1)
+            direc = 'r';
+        else
+            direc = 'd';
+    }
+    rpf = &rooms[rm];
+    /*
+     * Set up the movement variables, in two cases:
+     * first drawing one down.
+     */
+    if (direc == 'd')
+    {
+        rmt = rm + 3;                           /* room # of dest */
+        rpt = &rooms[rmt];                      /* room pointer of dest */
+        delta.x = 0;                            /* direction of move */
+        delta.y = 1;
+        spos.x = rpf->r_pos.x;                  /* start of move */
+        spos.y = rpf->r_pos.y;
+        epos.x = rpt->r_pos.x;                  /* end of move */
+        epos.y = rpt->r_pos.y;
+        if (!(rpf->r_flags & ISGONE))           /* if not gone pick door pos */
+        {
+            spos.x += rnd(rpf->r_max.x-2)+1;
+            spos.y += rpf->r_max.y-1;
+        }
+        if (!(rpt->r_flags & ISGONE))
+            epos.x += rnd(rpt->r_max.x-2)+1;
+        distance = abs(spos.y - epos.y) - 1;    /* distance to move */
+        turn_delta.y = 0;                       /* direction to turn */
+        turn_delta.x = (spos.x < epos.x ? 1 : -1);
+        offset = abs(spos.x - epos.x);  /* how far to turn */
+    }
+    else if (direc == 'r')                      /* setup for moving right */
+    {
+        rmt = rm + 1;
+        rpt = &rooms[rmt];
+        delta.x = 1;
+        delta.y = 0;
+        spos.x = rpf->r_pos.x;
+        spos.y = rpf->r_pos.y;
+        epos.x = rpt->r_pos.x;
+        epos.y = rpt->r_pos.y;
+        if (!(rpf->r_flags & ISGONE))
+        {
+            spos.x += rpf->r_max.x-1;
+            spos.y += rnd(rpf->r_max.y-2)+1;
+        }
+        if (!(rpt->r_flags & ISGONE))
+            epos.y += rnd(rpt->r_max.y-2)+1;
+        distance = abs(spos.x - epos.x) - 1;
+        turn_delta.y = (spos.y < epos.y ? 1 : -1);
+        turn_delta.x = 0;
+        offset = abs(spos.y - epos.y);
+    }
+    else
+        debug("error in connection tables");
+
+    /*
+     * Draw in the doors on either side of the passage or just put #'s
+     * if the rooms are gone.
+     */
+    if (!(rpf->r_flags & ISGONE)) door(rpf, &spos);
+    else
+    {
+        cmov(spos);
+        addch('#');
+    }
+    if (!(rpt->r_flags & ISGONE)) door(rpt, &epos);
+    else
+    {
+        cmov(epos);
+        addch('#');
+    }
+
+    /* How far can we move diagonally? */
+    max_diag = min(distance, offset);
+
+    /*
+     * Decide how many turns we will have.
+     */
+    for (i=0; i<3; i++) turn_dist[i] = 0;       /* Init distances */
+    if (max_diag > 0) {
+        int nturns;
+
+        for (i=0, nturns=0; i<3; i++) {
+            if (rnd(3 - i + nturns) == 0) {
+                nturns++;
+                turns[i] = 0;
+            }
+            else turns[i] = -1;
+        }
+    }
+    else {
+        /* Just use a straight line (middle turn) */
+        turns[0] = turns[2] = -1;
+        turns[1] = 0;
+    }
+
+    /*
+     * Now decide how long each turn will be (for those selected above).
+     */
+    while (max_diag > 0) {
+        for (i=0; i<3; i++) {
+            if (turns[i] >= 0 && max_diag > 0 && rnd(2) == 0) {
+                turn_dist[i]++;
+                max_diag--;
+            }
+        }
+    }
+    
+    /*
+     * If we have extra offset space, add it to the straight turn.
+     */
+    if (offset > distance) turn_dist[1] += offset - distance;
+
+    /*
+     * Decide where we want to make our turns.
+     * First calculate the offsets, then use those offsets to calculate
+     * the exact position relative to "distance."
+     */
+    turns[0] = rnd(distance - turn_dist[0] - turn_dist[2]);
+    turns[2] = rnd(distance - turn_dist[0] - turn_dist[2] - turns[0]);
+    turns[1] = rnd(distance - turn_dist[0] - turn_dist[2] -
+                   turns[0] - turns[2]);
+
+    turns[0] = distance - turns[0];
+    turns[1] = turns[0] - turn_dist[0] - turns[1];
+    turns[2] = turns[1] - turns[2];
+
+    /*
+     * Get ready to move...
+     */
+    curr.x = spos.x;
+    curr.y = spos.y;
+    while (distance > 0) {
+        /*
+         * Move to next row/column
+         */
+        curr.x += delta.x;
+        curr.y += delta.y;
+
+        /*
+         * Check if we are at a turn place; if so make a turn
+         */
+        for (i=0; i<3; i++) {
+            if (distance == turns[i] && turn_dist[i] > 0) {
+                /*
+                 * If this is the start of a straight path,
+                 * we might put in a right-angle turn (33% chance).
+                 */
+                if (i == 1 && rnd(3) == 0) {
+                    cmov(curr);
+                    addch(PASSAGE);
+                }
+
+                /* Now dig the turn */
+                while (turn_dist[i]--) {
+                    curr.x += turn_delta.x;
+                    curr.y += turn_delta.y;
+                    cmov(curr);
+                    addch(PASSAGE);
+                    if (i != 1) {       /* A diagonal */
+                        if (--distance > 0) {
+                            curr.x += delta.x;
+                            curr.y += delta.y;
+                        }
+                    }
+                }
+            }
+        }
+
+        if (distance > 0) {
+            /*
+             * Dig the passage.
+             */
+            cmov(curr);
+            addch(PASSAGE);
+            distance--;
+        }
+    }
+    curr.x += delta.x;
+    curr.y += delta.y;
+    if (!ce(curr, epos))
+        msg("Warning, connectivity problem (%d, %d) to (%d, %d).",
+            curr.y, curr.x, epos.y, epos.x);
+}
+
+/*
+ * Add a door or possibly a secret door
+ * also enters the door in the exits array of the room.
+ */
+
+door(rm, cp)
+register struct room *rm;
+register coord *cp;
+{
+    struct linked_list *newroom;
+    coord *exit;
+
+    cmov(*cp);
+
+	if (rnd(10) < (level - 1) && rnd(100) < 20)
+		addch(SECRETDOOR);
+	else
+		addch(DOOR);
+
+    /* Insert the new room into the linked list of rooms */
+    newroom = new_item(sizeof(coord));
+    exit = DOORPTR(newroom);
+    *exit = *cp;
+    attach(rm->r_exit, newroom);
+}
+