fix "65534 ships attacking", stop assuming a bignum can handle a fraction

2 files changed, 14 insertions, 10 deletions

diff --git a/bigfloat.h b/bigfloat.h
index bcfcfd1..359438d 100644
--- a/bigfloat.h
+++ b/bigfloat.h
@@ -9,11 +9,8 @@
 /* zero */
 #define BIG_0 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
 
-/* TODO: calculate bank interest differently: this bignum
-	implementation is floating point, but I might swap it out
-	for an int-based one! */
-/* 1.005 (bank interest) */
-#define BIG_1_005 { 0x40, 0x01, 0x00, 0x50, 0x00, 0x00 }
+/* bank interest rate is 0.5%, or .005, or 1/200 */
+#define BIG_200 { 0x41, 0x02, 0x00, 0x00, 0x00, 0x00 }
 
 /* bignum 100, used for score calculations in final_stats() */
 #define BIG_100 { 0x41, 0x01, 0x00, 0x00, 0x00, 0x00 }
diff --git a/taipan.c b/taipan.c
index ebd023e..c440625 100644
--- a/taipan.c
+++ b/taipan.c
@@ -263,7 +263,7 @@ char    *st[] = { "Critical", "  Poor", "  Fair",
 
 #ifdef BIGNUM
 bignum(bank) = BIG_0;
-bignum(interest_rate) = BIG_1_005;
+bignum(interest_denom) = BIG_200;
 bignum(big_max_ulong) = BIG_MAX_ULONG;
 #else
 unsigned long bank = 0;
@@ -1003,7 +1003,8 @@ int sea_battle(int id, int num_ships) {
          // if ((randi()%s0 > (num_ships * .6 / id)) && (num_ships > 2))
          if((randi()%s0 > ((num_ships / 2) / id)) && (num_ships > 2)) {
             static int ran;
-            ran = randi()%(num_ships / 3 / id) + 1;
+            // ran = randi()%(num_ships / 3 / id) + 1;
+            ran = randclamp(num_ships / 3 / id) + 1;
 
             num_ships -= ran;
             fight_stats(num_ships, orders);
@@ -1896,9 +1897,7 @@ void transfer(void)
 		a few bytes of code... but it makes the code a little
 		bigger instead! */
    int i, in_use;
-
    long amount = 0;
-
    if ((hkw_[0] == 0) && (hold_[0] == 0) &&
        (hkw_[1] == 0) && (hold_[1] == 0) &&
        (hkw_[2] == 0) && (hold_[2] == 0) &&
@@ -2006,6 +2005,9 @@ void transfer(void)
 
 void quit(void)
 {
+#ifdef BIGNUM
+	bignum(banktmp);
+#endif
 	unsigned char choice, sunk;
    int result = 0,
 		 damagepct;
@@ -2236,7 +2238,12 @@ void quit(void)
 	if(debt >= DEBT_MAX) wu_assassin = 1;
 
 #ifdef BIGNUM
-	big_mul(bank, bank, interest_rate);
+	// no good, assumes a bignum can handle a fraction
+	// big_mul(bank, bank, interest_rate);
+
+	// bank = bank + (bank / 200);
+	big_div(banktmp, bank, interest_denom);
+	big_add(bank, bank, banktmp);
 #else
 	/* bank calculation original formula was:
 			bank = bank + (bank * .005);