Function candle_light_range

src/light.c:842–877

Candlelight is proportional to the number of candles; minimum range is 2 rather than 1 for playability. */

/* Candlelight is proportional to the number of candles;
   minimum range is 2 rather than 1 for playability. */
int
candle_light_range(struct obj *obj)
{
    int radius;

    if (obj->otyp == CANDELABRUM_OF_INVOCATION) {
        /*
         *      The special candelabrum emits more light than the
         *      corresponding number of candles would.
         *       1..3 candles, range 2 (minimum range);
         *       4..6 candles, range 3 (normal lamp range);
         *          7 candles, range 4 (bright).
         */
        radius = (obj->spe < 4) ? 2 : (obj->spe < 7) ? 3 : 4;
    } else if (Is_candle(obj)) {
        /*
         *      Range is incremented quadratically. You can get the same
         *      amount of light as from a lamp with 4 candles, and
         *      even better light with 9 candles, and so on.
         *       1..3  candles, range 2;
         *       4..8  candles, range 3;
         *       9..15 candles, range 4; &c.
         */
        long n = obj->quan;

        radius = 1; /* always incremented at least once */
        while(radius*radius <= n && radius < MAX_RADIUS) {
            radius++;
        }
    } else {
        /* we're only called for lit candelabrum or candles */
        /* impossible("candlelight for %d?", obj->otyp); */
        radius = 3; /* lamp's value */
    }
    return radius;
}

/* light emitting artifact's range depends upon its curse/bless state */
int