Added some sound effects

nes/nescoundrel.c

@@ -11,6 +11,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+/* Constants section */
+
 #define SCREEN_WIDTH  32
 #define SCREEN_HEIGHT 28
 #define SCREEN_CENTER_X (SCREEN_WIDTH >> 1)
@@ -30,6 +32,8 @@
 #define GAME_YELLOW 2
 #define GAME_GREEN 3
 
+/* Graphics section */
+
 void ppu_off() {
   PPU.mask &= 0xE7;
 }
@@ -87,6 +91,83 @@ void colorxy(unsigned char x, unsigned char y, unsigned char palette) {
   PPU.vram.data = attr_byte;
 }
 
+/* Sound section */
+
+#define CPU 1789773 /* NTSC */
+
+unsigned int get_timer(int freq) {
+  return (unsigned int) ((CPU / 16 / freq) - 1);
+}
+
+void play_pulse(unsigned char idx, unsigned int freq, unsigned char len) {
+  unsigned int tm = get_timer(freq);
+  if(len > 31) len = 31;
+  if(idx > 1) idx = 0;
+  APU.pulse[idx].period_low = tm & 255;
+  APU.pulse[idx].len_period_high = (tm >> 8) | (len << 3);
+}
+
+void play_jingle(unsigned int n1f1,
+  unsigned int n1f2,
+  unsigned int n2f1,
+  unsigned int n2f2,
+  unsigned int n3f1,
+  unsigned int n3f2) {
+  unsigned int i, dl = 2000;
+  play_pulse(0, n1f1, 2);
+  play_pulse(1, n1f2, 2);
+  for(i=0;i<dl;++i);
+  play_pulse(0, n2f1, 2);
+  play_pulse(1, n2f2, 2);
+  for(i=0;i<dl;++i);
+  play_pulse(0, n3f1, 2);
+  play_pulse(1, n3f2, 2);
+}
+
+void init_sound() {
+  APU.status = 3;
+  APU.pulse[0].ramp = 0x8;
+  APU.pulse[1].ramp = 0x8;
+  APU.pulse[0].control = 0x9F;
+  APU.pulse[1].control = 0x9F;
+  waitvsync();
+}
+
+void beep_start() {
+  play_jingle(220, 440, 440, 660, 660, 880);
+}
+void beep_interact() {
+  play_jingle(440, 660, 220, 880, 440, 660);
+}
+void beep_enemy() {
+  play_jingle(440, 220, 220, 110, 110, 55);
+}
+void beep_weapon() {
+  play_jingle(660, 990, 440, 880, 660, 990);
+}
+void beep_potion() {
+  play_jingle(440, 660, 660, 990, 660, 880);
+}
+void beep_run() {
+  play_jingle(660, 880, 440, 660, 220, 440);
+}
+void beep_win() {
+  unsigned short i;
+  play_jingle(55, 110, 110, 220, 220, 440);
+  for(i=0;i<4000;++i);
+  play_jingle(440, 660, 660, 880, 880, 1760);
+  for(i=0;i<4000;++i);
+  play_jingle(880, 660, 660, 880, 880, 1760);
+}
+void beep_lose() {
+  play_jingle(110, 55, 220, 110, 110, 55);
+}
+void beep_err() {
+  play_jingle(330, 220, 330, 220, 330, 220);
+}
+
+/* Main game logic */
+
 void game_startup() {
   unsigned int entropy;
   unsigned char joy, i, j;
@@ -94,6 +175,7 @@ void game_startup() {
   _randomize();
 #endif
   entropy = rand();
+  init_sound();
   bgcolor(COLOR_BLACK);
   textcolor(0);
   init_palette();
@@ -139,6 +221,7 @@ void game_startup() {
     waitvsync();
   }
   srand(entropy);
+  beep_start();
   clrscr();
 }
 
@@ -165,6 +248,8 @@ void win_screen(int score) {
   chlinexy(0, 23, SCREEN_WIDTH);
   cputsxy(10, 25, "Press Start");
   ppu_on();
+  waitvsync();
+  beep_win();
   while(joy_input_wait() != KEY_ST);
 }
 
@@ -221,7 +306,6 @@ void render_room_item(short i, short v) {
         topleft_x, topleft_y,
         topright_x, bottomleft_y,
         text_x, text_y, cheight=7, cwidth=8, left_offset = 9;
-
   if(i == 0) {
     topleft_x = 8;
     topleft_y = 0;
@@ -325,7 +409,6 @@ unsigned char confirm(char *prompt) {
   cprintf("A=YES");
   gotoxy(statbase, SCREEN_HEIGHT-4);
   cprintf("B=NO");
-
   while(res > 1) {
     switch(joy_input_wait()) {
       case KEY_A: res = 1; break;
@@ -333,6 +416,7 @@ unsigned char confirm(char *prompt) {
       default: res = 2;
     }
   }
+  beep_interact();
   return res;
 }
 
@@ -361,6 +445,7 @@ void shuffle(char *array, unsigned int n) {
 void handle_monster(int val) {
   int healthlost = val;
   char monster_msg[(SCREEN_WIDTH-1)];
+  beep_enemy();
   if(weapon > 0 && val <= durability) {
     int weapondiff = val - weapon;
     if(weapondiff < 0) weapondiff = 0;
@@ -384,11 +469,13 @@ void handle_weapon(int val) {
   weapon = val;
   snprintf(status_msg, sizeof(status_msg), "You equip a %d-level weapon.", weapon);
   durability = 14; /* reset durability to max limit */
+  beep_weapon();
 }
 
 void handle_potion(unsigned char val) {
   if(potion_drank) {
     print_msg("Already drank a potion here.");
+    beep_err();
   } else {
     potion_drank = 1;
     hp += val;
@@ -396,6 +483,7 @@ void handle_potion(unsigned char val) {
     snprintf(status_msg, sizeof(status_msg), "You drink a %d-level potion.", val);
     if(deck_idx >= sizeof(deck) || deck[deck_idx] == 0)
       last_potion_val = val;
+    beep_potion();
   }
 }
 
@@ -460,6 +548,7 @@ int game() {
       break;
     } else if(ch == CH_INVAL) {
       print_msg("Invalid input!");
+      beep_err();
       continue;
     } else if(ch == CH_R) { /* run mechanics */
       /* Compact and rearrange the deck */
@@ -490,6 +579,7 @@ int game() {
       engaged = 0;
       last_room = 0; /* Since we added cards, it's not the last room anymore */
       print_msg("You ran from the room.");
+      beep_run();
     } else { /* engagement mechanics */
       engaged++; /* increase the amount of engaged cards */
       can_run = 0; /* Cannot run once engaged */
@@ -553,6 +643,7 @@ int main() {
       win_screen(score);
       break;
     } else {
+      beep_lose();
       snprintf(status_msg, sizeof(status_msg), "RIP! Score: %d. Restart?", score);
       if(!confirm(status_msg)) break;
     }