fp: Rejig the mob spawner to use a fixed-waypoint path

feely_pona.cpp

@@ -205,6 +205,7 @@ void TELY_DLL_Init(void *user_data)
     // NOTE: Hero
     {
         FP_GameEntity *entity           = FP_Game_MakeEntityPointerF(game, "Terry");
+        entity->type                    = FP_EntityType_Terry;
         entity->local_pos               = Dqn_V2_InitNx2(1334, 396);
         entity->action_to_anim_mapping  = game->terry_action_mappings;
         entity->size_scale              = Dqn_V2_InitNx1(0.25f);
@@ -282,13 +283,31 @@ void TELY_DLL_Init(void *user_data)
     // NOTE: Mob spawner ===========================================================================
     {
         FP_GameEntity *entity = FP_Game_MakeEntityPointerF(game, "Mob spawner");
-        entity->local_pos     = Dqn_V2_InitNx2(0, platform->core.window_size.y * .5f);
+        entity->local_pos     = Dqn_V2_InitNx2(50.f, platform->core.window_size.y * .5f);
         entity->flags        |= FP_GameEntityFlag_Clickable;
         entity->flags        |= FP_GameEntityFlag_MoveByKeyboard;
         entity->flags        |= FP_GameEntityFlag_MoveByMouse;
         entity->flags        |= FP_GameEntityFlag_MoveByGamepad;
         entity->flags        |= FP_GameEntityFlag_MobSpawner;
-        entity->spawn_cap     = 1;
+
+        entity->spawn_cap        = 16;
+        entity->spawn_list       = TELY_ChunkPool_New(game->chunk_pool, FP_GameEntitySpawnList);
+        entity->spawn_list->next = entity->spawn_list;
+        entity->spawn_list->prev = entity->spawn_list;
+
+        FP_Game_PushParentEntity(game, entity->handle);
+        {
+            {
+                FP_GameEntity *waypoint = FP_Game_MakeEntityPointerF(game, "Waypoint");
+                waypoint->local_pos     = Dqn_V2_InitNx2(800.f, 100.f);
+                waypoint->flags        |= FP_GameEntityFlag_Clickable;
+                waypoint->flags        |= FP_GameEntityFlag_MoveByKeyboard;
+                waypoint->flags        |= FP_GameEntityFlag_MoveByMouse;
+                waypoint->flags        |= FP_GameEntityFlag_MoveByGamepad;
+                waypoint->flags        |= FP_GameEntityFlag_MobSpawnerWaypoint;
+            }
+        }
+        FP_Game_PopParentEntity(game);
     }
 
     uint16_t font_size        = 18;
@@ -676,8 +695,11 @@ void FP_Update(TELY_Platform *platform, FP_Game *game, TELY_Renderer *renderer,
                         FP_EntitySmoochieState *state = DQN_CAST(FP_EntitySmoochieState *)&entity->action.state;
                         move_entity                 = *state == FP_EntitySmoochieState_Run || *state == FP_EntitySmoochieState_Idle;
                     } break;
+
+                    case FP_EntityType_Merchant: break;
                 }
 
+                if (move_entity) {
                     acceleration = dir_vector * 10000000.f;
                     if (dir_vector.x)
                         entity->direction = dir_vector.x > 0.f ? FP_GameDirection_Right : FP_GameDirection_Left;
@@ -685,6 +707,7 @@ void FP_Update(TELY_Platform *platform, FP_Game *game, TELY_Renderer *renderer,
                         entity->direction = dir_vector.y > 0.f ? FP_GameDirection_Down : FP_GameDirection_Up;
                 }
             }
+        }
 
         // NOTE: Stalk entity ======================================================================
         Dqn_V2 entity_world_pos = FP_Game_CalcEntityWorldPos(game, entity->handle);
@@ -718,17 +741,18 @@ void FP_Update(TELY_Platform *platform, FP_Game *game, TELY_Renderer *renderer,
                     }
                 }
             }
+        }
+        #endif
 
         // NOTE: Render the waypoints
         for (FP_GameWaypoint *waypoint = entity->waypoints->next; waypoint != entity->waypoints; waypoint = waypoint->next) {
-                Dqn_V2 circle_pos = Dqn_V2_InitNx2(waypoint->pos.x * game->tile_size + game->tile_size * .5f, waypoint->pos.y * game->tile_size + game->tile_size * .5f);
+            Dqn_V2 circle_pos = Dqn_V2_InitNx2(waypoint->pos.x, waypoint->pos.y);
             TELY_Render_CircleColourV4(renderer, circle_pos, 4.f, TELY_RenderShapeMode_Fill, TELY_COLOUR_MAGENTA_V4);
         }
 
         if (entity->waypoints->next != entity->waypoints) {
             FP_GameWaypoint *waypoint   = entity->waypoints->next;
-                Dqn_V2I target_tile         = entity->waypoints->next->pos;
+            Dqn_V2 target_pos           = Dqn_V2_InitV2I(entity->waypoints->next->pos);
-                Dqn_V2 target_pos           = Dqn_V2_InitNx2(target_tile.x * game->tile_size + game->tile_size *.5f, target_tile.y * game->tile_size + game->tile_size * .5f);
             Dqn_V2 entity_to_target_pos = target_pos - entity_world_pos;
 
             if (Dqn_V2_LengthSq(entity_to_target_pos) < DQN_SQUARED(entity->local_hit_box_size.x * .5f)) {
@@ -738,12 +762,10 @@ void FP_Update(TELY_Platform *platform, FP_Game *game, TELY_Renderer *renderer,
             } else {
                 Dqn_V2 entity_to_target_pos_norm = Dqn_V2_Normalise(entity_to_target_pos);
                 if (acceleration.x == 0 && acceleration.y == 0) {
-                        acceleration = entity_to_target_pos_norm * 700'000.f;
+                    acceleration = entity_to_target_pos_norm * 1'000'000.f;
                 }
             }
         }
-        }
-        #endif
 
         // NOTE: Core equations of motion ==========================================================
         bool has_collision = false;
@@ -869,12 +891,51 @@ void FP_Update(TELY_Platform *platform, FP_Game *game, TELY_Renderer *renderer,
 
         // NOTE: Mob spawner =======================================================================
         if (entity->flags & FP_GameEntityFlag_MobSpawner) {
-            if (entity->spawn_count < entity->spawn_cap) {
+            // NOTE: Check if any spawned entities dies to remove it from the spawn cap tracker
+            for (FP_GameEntitySpawnList *link = entity->spawn_list->next; link != entity->spawn_list;) {
+                FP_GameEntity *spawned_entity = FP_Game_GetEntity(game, link->entity);
+                if (spawned_entity) {
+                    // NOTE: Spawned entity is still alive
+                    link = link->next;
+                    continue;
+                }
+
+                DQN_ASSERT(entity->spawn_count);
+                entity->spawn_count--;
+
+                // NOTE: Entity is dead remove it from the linked list
+                FP_GameEntitySpawnList *link_to_delete = link;
+                link->next->prev                       = link->prev;
+                link->prev->next                       = link->next;
+                link                                   = link->next;
+                TELY_ChunkPool_Dealloc(game->chunk_pool, link_to_delete);
+            }
+
+            if (entity->spawn_count < entity->spawn_cap) { // NOTE: Spawn new entities
                 if (input->timer_s >= entity->next_spawn_timestamp_s) {
                     entity->next_spawn_timestamp_s = DQN_CAST(uint64_t)(input->timer_s + 5.f);
                     entity->spawn_count++;
 
-                    FP_Game_EntityAddMob(game, entity_world_pos);
+                    FP_GameEntitySpawnList *item = TELY_ChunkPool_New(game->chunk_pool, FP_GameEntitySpawnList);
+                    item->entity                 = FP_Game_EntityAddMob(game, entity_world_pos);
+                    FP_SentinelDoublyLinkedList_Insert(entity->spawn_list, item);
+
+                    // NOTE: Setup the mob with a sentinel waypoint
+                    FP_GameEntity *mob = FP_Game_GetEntity(game, item->entity);
+                    mob->waypoints     = TELY_ChunkPool_New(game->chunk_pool, FP_GameWaypoint);
+                    mob->waypoints->next = mob->waypoints;
+                    mob->waypoints->prev = mob->waypoints;
+
+                    for (FP_GameEntity *waypoint_entity = entity->first_child; waypoint_entity; waypoint_entity = waypoint_entity->next) {
+                        if ((waypoint_entity->flags & FP_GameEntityFlag_MobSpawnerWaypoint) == 0)
+                            continue;
+
+                        // NOTE: Add the waypoint
+                        FP_GameWaypoint *waypoint = TELY_ChunkPool_New(game->chunk_pool, FP_GameWaypoint);
+                        Dqn_V2 waypoint_pos       = FP_Game_CalcEntityWorldPos(game, waypoint_entity->handle);
+                        waypoint->pos             = Dqn_V2I_InitV2(waypoint_pos);
+                        FP_SentinelDoublyLinkedList_Insert(mob->waypoints, waypoint);
+                    }
                 }
             }
         }

feely_pona.h

@@ -3,6 +3,12 @@
 #include "feely_pona_unity.h"
 #endif
 
+#define FP_SentinelDoublyLinkedList_Insert(list, item) \
+    item->next       = list; \
+    item->prev       = list->prev; \
+    item->next->prev = item; \
+    item->prev->next = item;
+
 enum FP_ProfileZone
 {
     FP_ProfileZone_FPUpdate = TELY_ProfileZone_Count,

feely_pona_entity.h

@@ -5,6 +5,7 @@
 
 enum FP_EntityType
 {
+    FP_EntityType_Nil,
     FP_EntityType_Terry,
     FP_EntityType_Smoochie,
     FP_EntityType_Merchant,

feely_pona_game.cpp

@@ -292,6 +292,9 @@ static void FP_Game_DetachEntityIntoFreeList(FP_Game *game, FP_GameEntityHandle
     if (entity->name.size)
         TELY_ChunkPool_Dealloc(game->chunk_pool, entity->name.data);
 
+    if (entity->spawn_list)
+        TELY_ChunkPool_Dealloc(game->chunk_pool, entity->spawn_list);
+
     if (new_entity_generation > entity_generation) {
         // NOTE: Update the incremented handle disassociating all prior handles
         // to this entity which would reference older generation values
@@ -672,7 +675,7 @@ static FP_GameEntityHandle FP_Game_EntityAddMob(FP_Game *game, Dqn_V2 pos)
     entity->local_pos               = pos;
     entity->size_scale              = Dqn_V2_InitNx1(.25f);
     entity->action_to_anim_mapping  = game->smoochie_action_mappings;
-    entity->local_hit_box_size      = Dqn_V2_InitV2I(game->smoochie_sprite_sheet.sprite_size);
+    entity->local_hit_box_size      = Dqn_V2_InitNx2(428, 471) * entity->size_scale;
     entity->flags                  |= FP_GameEntityFlag_Clickable;
     entity->flags                  |= FP_GameEntityFlag_MoveByKeyboard;
     entity->flags                  |= FP_GameEntityFlag_MoveByMouse;

feely_pona_game.h

@@ -13,6 +13,7 @@ enum FP_GameEntityFlag
     FP_GameEntityFlag_DeriveHitBoxFromChildrenBoundingBox = 1 << 5,
     FP_GameEntityFlag_NonTraversable                      = 1 << 6,
     FP_GameEntityFlag_MobSpawner                          = 1 << 7,
+    FP_GameEntityFlag_MobSpawnerWaypoint                  = 1 << 8,
 };
 
 enum FP_GameShapeType
@@ -52,6 +53,13 @@ struct FP_GameWaypoint
     FP_GameWaypoint *prev;
 };
 
+struct FP_GameEntitySpawnList
+{
+    FP_GameEntityHandle     entity;
+    FP_GameEntitySpawnList *next;
+    FP_GameEntitySpawnList *prev;
+};
+
 enum FP_GameEntityActionFlag
 {
     FP_GameEntityActionFlag_StateTransition = 1 << 0,
@@ -112,6 +120,8 @@ struct FP_GameEntity
     Dqn_V2                                 attack_box_size;
     Dqn_V2                                 attack_box_offset;
 
+    Dqn_FArray<Dqn_V2, 8>                  spawner_waypoints;
+    FP_GameEntitySpawnList                *spawn_list;
     uint64_t                               next_spawn_timestamp_s;
     uint64_t                               spawn_count;
     uint64_t                               spawn_cap;