Fix #8584: Ducks spawning function doesnt check tiles 0..63 (original bug) (#8614)

distribution/changelog.txt

@@ -54,6 +54,7 @@
 - Fix: [#8469] Crash modifying colour on hacked rides.
 - Fix: [#8508] Underground roto-drop is not going up.
 - Fix: [#8555] Multiplayer window text limits are not computed properly.
+- Fix: [#8584] Duck spawning function does not check tiles with x or y coordinate of 0..63 (original bug).
 - Fix: [#8588] Guest list scrolling breaks above ~2000 guests.
 - Fix: [#8591] Game loop does not run at a consistent tick rate of 40 Hz.
 - Improved: [#2940] Allow mouse-dragging to set patrol area (Singleplayer only).

src/openrct2/network/Network.cpp

@@ -30,7 +30,7 @@
 // This string specifies which version of network stream current build uses.
 // It is used for making sure only compatible builds get connected, even within
 // single OpenRCT2 version.
-#define NETWORK_STREAM_VERSION "22"
+#define NETWORK_STREAM_VERSION "23"
 #define NETWORK_STREAM_ID OPENRCT2_VERSION "-" NETWORK_STREAM_VERSION
 
 static rct_peep* _pickup_peep = nullptr;

src/openrct2/scenario/Scenario.cpp

@@ -426,11 +426,13 @@ static int32_t scenario_create_ducks()
 {
     int32_t i, j, r, c, x, y, waterZ, centreWaterZ, x2, y2;
 
+    // Originally, this function generated coordinates from 64 to 191.
+    // It now generates coordinates from 0 to 255, so smaller maps may also spawn ducks.
     r = scenario_rand();
-    x = ((r >> 16) & 0xFFFF) & 0x7F;
-    y = (r & 0xFFFF) & 0x7F;
-    x = (x + 64) * 32;
-    y = (y + 64) * 32;
+    x = ((r >> 16) & 0xFFFF) % MAXIMUM_MAP_SIZE_TECHNICAL;
+    y = (r & 0xFFFF) % MAXIMUM_MAP_SIZE_TECHNICAL;
+    x = x * 32;
+    y = y * 32;
 
     if (!map_is_location_in_park({ x, y }))
         return 0;