Refactoring to limit scope of guardCount

Author: CJLove

src/Makefile

@@ -13,7 +13,7 @@ OBJ = $(SRC:%.c=%.o)
 #	cl65 -t cx16 -I $(INCLUDE) -Oi $<
 
 lode_runner: mainloop.c $(SRC)
-	cl65 -t cx16 --listing test.txt $(INCLUDES) $(LIBRARIES) -Oi -o lode_runner.prg mainloop.c $(SRC) libX16.lib cx16.lib
+	cl65 -t cx16 $(INCLUDES) $(LIBRARIES) -Oi -o lode_runner.prg mainloop.c $(SRC) libX16.lib cx16.lib
 
 PALETTE.BIN: ../assets/palette.txt
 	../scripts/ascii2bin.py --input ../assets/palette.txt --output PALETTE.BIN --addr 1000

src/guard.c

@@ -10,7 +10,7 @@ struct guard_t guard[MAX_GUARDS];
 
 struct shakeGuard_t shake[MAX_GUARDS];
 
-uint8_t guardCount;
+static uint8_t guardCount;
 
 void addGuardToShakeQueue(uint8_t id);
 
@@ -111,38 +111,43 @@ void clearGuards()
     moveId = 0;
 }
 
-void initGuard(uint8_t x, uint8_t y)
+uint8_t initGuard(uint8_t x, uint8_t y)
 {
-    uint8_t i = guardCount;
-    uint16_t xPos = x * TILE_W;
-    uint16_t yPos = y * TILE_H;
-
-    guard[i].x = x;
-    guard[i].y = y;
-    guard[i].xOffset = 0;
-    guard[i].yOffset = 0;
-    guard[i].holePosX = 0;
-    guard[i].holePosY = 0;
-    guard[i].action = ACT_UNKNOWN;
-    guard[i].direction = ACT_RIGHT;
-    guard[i].idx = 0;
-
-    guard[i].sequence = RUN_SEQUENCE;
-
-    // Sprite attribute settings
-    vpoke((GUARD_1 >> 5) & 0xff, 0x1f5000 + 8 * (i + 1));  // Attr0
-    VERA.data0 = (GUARD_1 >> 13) & 0xf;                    // Attr1
-    VERA.data0 = xPos & 0xff;                              // Attr2
-    VERA.data0 = xPos >> 8;                                // Attr3
-    VERA.data0 = yPos & 0xff;                              // Attr4
-    VERA.data0 = yPos >> 8;                                // Attr5
-    VERA.data0 = (3 << 2);                                 // Attr6
-    VERA.data0 = 0;                                        // Attr7
+    if (guardCount < MAX_GUARDS) {
+        uint8_t i = guardCount;
+        uint16_t xPos = x * TILE_W;
+        uint16_t yPos = y * TILE_H;
+
+        guard[i].x = x;
+        guard[i].y = y;
+        guard[i].xOffset = 0;
+        guard[i].yOffset = 0;
+        guard[i].holePosX = 0;
+        guard[i].holePosY = 0;
+        guard[i].action = ACT_UNKNOWN;
+        guard[i].direction = ACT_RIGHT;
+        guard[i].idx = 0;
+
+        guard[i].sequence = RUN_SEQUENCE;
+
+        // Sprite attribute settings
+        vpoke((GUARD_1 >> 5) & 0xff, 0x1f5000 + 8 * (i + 1));  // Attr0
+        VERA.data0 = (GUARD_1 >> 13) & 0xf;                    // Attr1
+        VERA.data0 = xPos & 0xff;                              // Attr2
+        VERA.data0 = xPos >> 8;                                // Attr3
+        VERA.data0 = yPos & 0xff;                              // Attr4
+        VERA.data0 = yPos >> 8;                                // Attr5
+        VERA.data0 = (3 << 2);                                 // Attr6
+        VERA.data0 = 0;                                        // Attr7
 
 #ifdef DEBUG
-    // displayGuard(guardCount);
+        // displayGuard(guardCount);
 #endif
-    guardCount++;
+        guardCount++;
+        return 1;
+    } else {
+        return 0;
+    }
 }
 
 int8_t guardId(uint8_t x, uint8_t y)

src/guard.h

@@ -50,18 +50,16 @@ extern struct guard_t guard[MAX_GUARDS];
 
 extern struct shakeGuard_t shake[MAX_GUARDS];
 
-extern uint8_t guardCount;
-
-void clearGuards(void);
-void initGuard(uint8_t x, uint8_t y);
-int8_t guardId(uint8_t x, uint8_t y);
-int8_t guardAlive(uint8_t x, uint8_t y);
-void guardReborn(uint8_t x, uint8_t y);
-void removeFromShake(uint8_t id);
+extern void clearGuards(void);
+extern uint8_t initGuard(uint8_t x, uint8_t y);
+extern int8_t guardId(uint8_t x, uint8_t y);
+extern int8_t guardAlive(uint8_t x, uint8_t y);
+extern void guardReborn(uint8_t x, uint8_t y);
+extern void removeFromShake(uint8_t id);
 
 // Entry point from main loop to shake guards prior to 
 // them climbing out of holes
-void processGuardShake(void);
+extern void processGuardShake(void);
 
 // Entry point from main loop to move guards
 extern void moveGuard(void);

src/levels.c

@@ -167,15 +167,14 @@ int loadLevel(uint8_t world, uint8_t level)
 
                 switch (tile1) {
                     case TILE_GUARD:
-                        // TODO: Initiaze guard and set tile as blank
-                        map[idx * 2][row].act = TILE_GUARD;
-                        map[idx * 2][row].base = TILE_BLANK;
-                        if (guardCount == MAX_GUARDS) {
+                        if (initGuard(idx*2,row)) {
+                            map[idx * 2][row].act = TILE_GUARD;
+                            map[idx * 2][row].base = TILE_BLANK;
+                        } else {
                             // Too many guards
                             map[idx * 2][row].act = TILE_BLANK;
                             continue;
                         }
-                        initGuard(idx*2,row);
                         break;
                     case TILE_RUNNER:
                         // If runner hasn't been found yet, then initialize
@@ -200,15 +199,14 @@ int loadLevel(uint8_t world, uint8_t level)
                 }
                 switch (tile2) {
                     case TILE_GUARD:
-                        // TODO: Initiaze guard and set tile as blank
-                        map[idx * 2 + 1][row].act = TILE_GUARD;
-                        map[idx * 2 + 1][row].base = TILE_BLANK;
-                        if (guardCount == MAX_GUARDS) {
+                        if (initGuard(idx*2+1,row)) {
+                            map[idx * 2 + 1][row].act = TILE_GUARD;
+                            map[idx * 2 + 1][row].base = TILE_BLANK;
+                        } else {
                             // Too many guards
                             map[idx * 2 + 1][row].act = TILE_BLANK;
                             continue;
                         }
-                        initGuard(idx*2+1,row);
                         break;
                     case TILE_RUNNER:
                         // If runner hasn't been found yet, then initialize