Simplify fountain code. Name sprite fields. Fix warning

Fountain jumping code has been sped up slightly so that the code can be simplified and not require rolling over a unsigned int. Also removed setting direction of the fountain as the field was not used.

src/openrct2/paint/sprite/misc.c

@@ -121,7 +121,7 @@ void misc_paint(paint_session * session, rct_sprite *misc, sint32 imageDirection
             }
 
             uint32 baseImageId = (jumpingFountain.misc_identifier == SPRITE_MISC_JUMPING_FOUNTAIN_SNOW) ? 23037 : 22973;
-            uint32 imageId = baseImageId + ebx * 16 + jumpingFountain.var_26b;
+            uint32 imageId = baseImageId + ebx * 16 + jumpingFountain.frame;
             if (al & 1) {
                 switch (ebx) {
                     case 0:

src/openrct2/paint/sprite/sprite.h

@@ -32,6 +32,7 @@ extern "C" {
     void litter_paint(paint_session * session, rct_litter *litter, sint32 imageDirection);
     void peep_paint(paint_session * session, rct_peep *peep, sint32 imageDirection);
 
+    extern const uint32 vehicle_particle_base_sprites[5];
 #ifdef __cplusplus
 }
 #endif

src/openrct2/rct1/S4Importer.cpp

@@ -1662,8 +1662,8 @@ private:
     {
         dst->fountain_flags = src->fountain_flags;
         dst->iteration = src->iteration;
-        dst->var_26a = src->var_26a;
-        dst->var_26b = src->var_26b;
+        dst->num_ticks_alive = src->num_ticks_alive;
+        dst->frame = src->frame;
     }
 
     void ImportBalloon(rct_balloon * dst, rct_balloon * src)

src/openrct2/world/Fountain.cpp

@@ -183,7 +183,6 @@ extern "C"
         if (jumpingFountain != nullptr)
         {
             jumpingFountain->iteration = iteration;
-            jumpingFountain->var_2E = direction;
             jumpingFountain->fountain_flags = flags;
             jumpingFountain->sprite_direction = direction << 3;
             jumpingFountain->sprite_width = 33;
@@ -194,42 +193,46 @@ extern "C"
             jumpingFountain->misc_identifier = type == JUMPING_FOUNTAIN_TYPE_SNOW ?
                 SPRITE_MISC_JUMPING_FOUNTAIN_SNOW :
                 SPRITE_MISC_JUMPING_FOUNTAIN_WATER;
-            jumpingFountain->var_26 = 0;
+            jumpingFountain->num_ticks_alive = 0;
+            jumpingFountain->frame = 0;
         }
     }
 
     void jumping_fountain_update(rct_jumping_fountain * jumpingFountain)
     {
-        sint32 original_var_26a = jumpingFountain->var_26a;
-        jumpingFountain->var_26a += 160;
-        if (original_var_26a <= 255 - 160)
+        jumpingFountain->num_ticks_alive++;
+        // Originaly this would not update the frame on the following
+        // ticks: 1, 3, 6, 9, 11, 14, 17, 19, 22, 25
+        // This change was to simplefy the code base. There is a small increase
+        // in speed of the fountain jump because of this change.
+        if ((jumpingFountain->num_ticks_alive % 3) == 0)
         {
             return;
         }
 
         invalidate_sprite_0((rct_sprite *)jumpingFountain);
-        jumpingFountain->var_26b++;
+        jumpingFountain->frame++;
 
         switch (jumpingFountain->misc_identifier) {
         case SPRITE_MISC_JUMPING_FOUNTAIN_WATER:
-            if (jumpingFountain->var_26b == 11 && (jumpingFountain->fountain_flags & FOUNTAIN_FLAG::FAST))
+            if (jumpingFountain->frame == 11 && (jumpingFountain->fountain_flags & FOUNTAIN_FLAG::FAST))
             {
                 jumping_fountain_continue(jumpingFountain);
             }
-            if (jumpingFountain->var_26b == 16 && !(jumpingFountain->fountain_flags & FOUNTAIN_FLAG::FAST))
+            if (jumpingFountain->frame == 16 && !(jumpingFountain->fountain_flags & FOUNTAIN_FLAG::FAST))
             {
                 jumping_fountain_continue(jumpingFountain);
             }
             break;
         case SPRITE_MISC_JUMPING_FOUNTAIN_SNOW:
-            if (jumpingFountain->var_26b == 16)
+            if (jumpingFountain->frame == 16)
             {
                 jumping_fountain_continue(jumpingFountain);
             }
             break;
         }
 
-        if (jumpingFountain->var_26b == 16)
+        if (jumpingFountain->frame == 16)
         {
             sprite_remove((rct_sprite*)jumpingFountain);
         }

src/openrct2/world/Particle.cpp

@@ -17,12 +17,9 @@
 #include "../audio/audio.h"
 #include "../core/Util.hpp"
 #include "../scenario/scenario.h"
+#include "../paint/sprite/sprite.h"
 #include "sprite.h"
 
-extern "C" {
-    extern const uint32 vehicle_particle_base_sprites[5];
-}
-
 /**
  *
  *  rct2: 0x006735A1

src/openrct2/world/sprite.h

@@ -175,7 +175,7 @@ typedef struct rct_jumping_fountain {
     uint8 linked_list_type_offset;  // 0x08 Valid values are SPRITE_LINKEDLIST_OFFSET_...
     uint8 sprite_height_negative;
     uint16 sprite_index;            // 0x0A
-    uint16 flags;           // 0x0C
+    uint16 flags;                   // 0x0C
     sint16 x;                       // 0x0E
     sint16 y;                       // 0x10
     sint16 z;                       // 0x12
@@ -184,15 +184,9 @@ typedef struct rct_jumping_fountain {
     uint8 pad_16[0x8];
     uint8 sprite_direction;         // 0x1E
     uint8 pad_1F[0x7];
-    union {
-        uint16 var_26;
-        struct {
-            uint8 var_26a;
-            uint8 var_26b;
-        };
-    };
-    uint8 pad_28[0x6];
-    uint8 var_2E;
+    uint8 num_ticks_alive;          // 0x26
+    uint8 frame;                    // 0x27
+    uint8 pad_28[0x7];              // 0x28 Originally var_2E was set to direction but it was unused.
     uint8 fountain_flags;           // 0x2F
     sint16 target_x;                // 0x30
     sint16 target_y;                // 0x32