Fix #8584: Duck spawn search now uses entire map (#9743)

distribution/changelog.txt

@@ -8,6 +8,7 @@
 - Fix: [#7690] Problem with guests freezing on certain tiles of path.
 - Fix: [#7883] Headless server log is stored incorrectly if server name contains CJK in Ubuntu
 - Fix: [#8136] Excessive lateral G penalty is too excessive.
+- Fix: [#8584] Duck spawning function does not check tiles with x or y coordinate of 0..64 (Original bug)
 - Fix: [#9179] Crash when modifying a ride occasionally.
 - Fix: [#9533] Door sounds not playing.
 - Fix: [#9574] Text overflow in scenario objective window when using CJK languages.

src/openrct2/network/Network.cpp

@@ -34,7 +34,7 @@
 // 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 "16"
+#define NETWORK_STREAM_VERSION "17"
 #define NETWORK_STREAM_ID OPENRCT2_VERSION "-" NETWORK_STREAM_VERSION
 
 static Peep* _pickup_peep = nullptr;

src/openrct2/scenario/Scenario.cpp

@@ -18,6 +18,7 @@
 #include "../ParkImporter.h"
 #include "../audio/audio.h"
 #include "../config/Config.h"
+#include "../core/Guard.hpp"
 #include "../core/Random.hpp"
 #include "../interface/Viewport.h"
 #include "../localisation/Date.h"
@@ -415,60 +416,69 @@ void scenario_update()
     }
     scenario_update_daynight_cycle();
 }
-
 /**
  *
  *  rct2: 0x006744A9
  */
 static int32_t scenario_create_ducks()
 {
-    int32_t i, j, r, c, x, y, waterZ, centreWaterZ, x2, y2;
+    CoordsXY centrePos;
+    centrePos.x = 64 + (scenario_rand_max(MAXIMUM_MAP_SIZE_PRACTICAL) * 32);
+    centrePos.y = 64 + (scenario_rand_max(MAXIMUM_MAP_SIZE_PRACTICAL) * 32);
 
-    r = scenario_rand();
-    x = ((r >> 16) & 0xFFFF) & 0x7F;
-    y = (r & 0xFFFF) & 0x7F;
-    x = (x + 64) * 32;
-    y = (y + 64) * 32;
+    Guard::Assert(map_is_location_valid(centrePos));
 
-    if (!map_is_location_in_park({ x, y }))
+    if (!map_is_location_in_park(centrePos))
         return 0;
 
-    centreWaterZ = (tile_element_water_height({ x, y }));
+    int32_t centreWaterZ = (tile_element_water_height(centrePos));
     if (centreWaterZ == 0)
         return 0;
 
-    // Check 7x7 area around centre tile
-    x2 = x - (32 * 3);
-    y2 = y - (32 * 3);
-    c = 0;
-    for (i = 0; i < 7; i++)
-    {
-        for (j = 0; j < 7; j++)
-        {
-            waterZ = (tile_element_water_height({ x2, y2 }));
-            if (waterZ == centreWaterZ)
-                c++;
+    // Check NxN area around centre tile defined by SquareSize
+    constexpr int32_t SquareSize = 7;
+    constexpr int32_t SquareCentre = SquareSize / 2;
 
-            x2 += 32;
+    CoordsXY innerPos{ centrePos.x - (32 * SquareCentre), centrePos.y - (32 * SquareCentre) };
+    int32_t waterTiles = 0;
+    for (int32_t y = 0; y < SquareSize; y++)
+    {
+        for (int32_t x = 0; x < SquareSize; x++)
+        {
+            if (!map_is_location_valid(innerPos))
+                continue;
+
+            if (!map_is_location_in_park(innerPos))
+                continue;
+
+            int32_t waterZ = (tile_element_water_height(innerPos));
+            if (waterZ == centreWaterZ)
+                waterTiles++;
+
+            innerPos.x += 32;
         }
-        x2 -= 224;
-        y2 += 32;
+        innerPos.x -= SquareSize * 32;
+        innerPos.y += 32;
     }
 
     // Must be at least 25 water tiles of the same height in 7x7 area
-    if (c < 25)
+    if (waterTiles < 25)
         return 0;
 
     // Set x, y to the centre of the tile
-    x += 16;
-    y += 16;
-    c = (scenario_rand() & 3) + 2;
-    for (i = 0; i < c; i++)
+    centrePos.x += 16;
+    centrePos.y += 16;
+
+    int32_t duckCount = (scenario_rand() & 3) + 2;
+    for (int32_t i = 0; i < duckCount; i++)
     {
-        r = scenario_rand();
-        x2 = (r >> 16) & 0x7F;
-        y2 = (r & 0xFFFF) & 0x7F;
-        create_duck(x + x2 - 64, y + y2 - 64);
+        int32_t r = scenario_rand();
+        innerPos.x = (r >> 16) & 0x7F;
+        innerPos.y = (r & 0xFFFF) & 0x7F;
+
+        CoordsXY targetPos{ centrePos.x + innerPos.x - 64, centrePos.y + innerPos.y - 64 };
+        Guard::Assert(map_is_location_valid(targetPos));
+        create_duck(targetPos);
     }
 
     return 1;

src/openrct2/world/Duck.cpp

@@ -305,42 +305,45 @@ uint32_t rct_duck::GetFrameImage(int32_t direction) const
     return imageId;
 }
 
-void create_duck(int32_t targetX, int32_t targetY)
+void create_duck(const CoordsXY& pos)
 {
     rct_sprite* sprite = create_sprite(SPRITE_IDENTIFIER_MISC);
-    if (sprite != nullptr)
+    if (sprite == nullptr)
+        return;
+
+    CoordsXY targetPos = pos;
+
+    int32_t offsetXY = scenario_rand() & 0x1E;
+    targetPos.x += offsetXY;
+    targetPos.y += offsetXY;
+
+    sprite->duck.sprite_identifier = SPRITE_IDENTIFIER_MISC;
+    sprite->duck.type = SPRITE_MISC_DUCK;
+    sprite->duck.sprite_width = 9;
+    sprite->duck.sprite_height_negative = 12;
+    sprite->duck.sprite_height_positive = 9;
+    sprite->duck.target_x = targetPos.x;
+    sprite->duck.target_y = targetPos.y;
+    uint8_t direction = scenario_rand() & 3;
+    switch (direction)
     {
-        sprite->duck.sprite_identifier = SPRITE_IDENTIFIER_MISC;
-        sprite->duck.type = SPRITE_MISC_DUCK;
-        sprite->duck.sprite_width = 9;
-        sprite->duck.sprite_height_negative = 12;
-        sprite->duck.sprite_height_positive = 9;
-        int32_t offsetXY = scenario_rand() & 0x1E;
-        targetX += offsetXY;
-        targetY += offsetXY;
-        sprite->duck.target_x = targetX;
-        sprite->duck.target_y = targetY;
-        uint8_t direction = scenario_rand() & 3;
-        switch (direction)
-        {
-            case 0:
-                targetX = 8191 - (scenario_rand() & 0x3F);
-                break;
-            case 1:
-                targetY = scenario_rand() & 0x3F;
-                break;
-            case 2:
-                targetX = scenario_rand() & 0x3F;
-                break;
-            case 3:
-                targetY = 8191 - (scenario_rand() & 0x3F);
-                break;
-        }
-        sprite->duck.sprite_direction = direction << 3;
-        sprite_move(targetX, targetY, 496, sprite);
-        sprite->duck.state = DUCK_STATE::FLY_TO_WATER;
-        sprite->duck.frame = 0;
+        case 0:
+            targetPos.x = 8191 - (scenario_rand() & 0x3F);
+            break;
+        case 1:
+            targetPos.y = scenario_rand() & 0x3F;
+            break;
+        case 2:
+            targetPos.x = scenario_rand() & 0x3F;
+            break;
+        case 3:
+            targetPos.y = 8191 - (scenario_rand() & 0x3F);
+            break;
     }
+    sprite->duck.sprite_direction = direction << 3;
+    sprite_move(targetPos.x, targetPos.y, 496, sprite);
+    sprite->duck.state = DUCK_STATE::FLY_TO_WATER;
+    sprite->duck.frame = 0;
 }
 
 void duck_update(rct_duck* duck)

src/openrct2/world/Sprite.h

@@ -227,7 +227,7 @@ void balloon_update(rct_balloon* balloon);
 ///////////////////////////////////////////////////////////////
 // Duck
 ///////////////////////////////////////////////////////////////
-void create_duck(int32_t targetX, int32_t targetY);
+void create_duck(const CoordsXY& pos);
 void duck_update(rct_duck* duck);
 void duck_press(rct_duck* duck);
 void duck_remove_all();