Add ent system base

src/dusk/CMakeLists.txt

@@ -24,4 +24,4 @@ target_sources(${DUSK_TARGET_NAME}
 # Subdirs
 add_subdirectory(assert)
 add_subdirectory(render)
-add_subdirectory(entity)
+add_subdirectory(overworld)

src/dusk/overworld/CMakeLists.txt

@@ -8,6 +8,7 @@ target_sources(${DUSK_TARGET_NAME}
   PRIVATE
     entity.c
     overworld.c
+    player.c
 )
 
 # Subdirs

src/dusk/overworld/entity.c

@@ -8,10 +8,32 @@
 #include "entity.h"
 #include "assert/assert.h"
 
+entitycallback_t ENTITY_CALLBACKS[ENTITY_TYPE_COUNT] = {
+  { NULL },
+  { playerInit, playerUpdate }
+};
+
 entity_t ENTITY_TEST;
 
-void entityInit(entity_t *ent) {
+void entityInit(
+  entity_t *ent,
+  const entitytype_t type
+) {
   assertNotNull(ent, "Entity cannot be NULL");
+  assertTrue(type < ENTITY_TYPE_COUNT, "Invalid entity type");
 
+  // Init values
   memset(ent, 0, sizeof(entity_t));
+  ent->type = type;
+
+  assertNotNull(ENTITY_CALLBACKS[type].init, "Entity type init callback err.");
+  ENTITY_CALLBACKS[type].init(ent);
+}
+
+void entityUpdate(entity_t *ent) {
+  assertNotNull(ent, "Entity cannot be NULL");
+  assertTrue(ent->type < ENTITY_TYPE_COUNT, "Invalid entity type");
+
+  assertNotNull(ENTITY_CALLBACKS[ent->type].update, "Entity type update err.");
+  ENTITY_CALLBACKS[ent->type].update(ent);
 }

src/dusk/overworld/entity.h

@@ -6,12 +6,52 @@
  */
 
 #pragma once
-#include "dusk.h"
+#include "player.h"
+
+typedef enum {
+  ENTITY_TYPE_NULL,
+  ENTITY_TYPE_PLAYER,
+} entitytype_t;
+
+#define ENTITY_TYPE_COUNT 2
 
 typedef struct {
-  vec3 position;
+  void (*init)(entity_t *);
+  void (*update)(entity_t *);
+} entitycallback_t;
+
+typedef enum {
+  FACING_DIRECTION_SOUTH,
+  FACING_DIRECTION_EAST,
+  FACING_DIRECTION_NORTH,
+  FACING_DIRECTION_WEST
+} facingdir_t;
+
+typedef struct _entity_t {
+  uint8_t x, y;
+  uint8_t subX, subY;
+  facingdir_t direction;
+  entitytype_t type;
+
+  union {
+    player_t player;
+  };
 } entity_t;
 
-extern entity_t ENTITY_TEST;
+/**
+ * Initializes an entity.
+ * 
+ * @param entity The entity to initialize.
+ * @param type The type of entity to initialize.
+ */
+void entityInit(
+  entity_t *entity,
+  const entitytype_t type
+);
 
-void entityInit(entity_t *entity);
+/**
+ * Updates an entity.
+ * 
+ * @param entity The entity to update.
+ */
+void entityUpdate(entity_t *entity);

src/dusk/overworld/overworld.c

@@ -7,8 +7,13 @@
 
 #include "overworld.h"
 
-void overworldInit() {
+overworld_t OVERWORLD;
 
+void overworldInit() {
+  memset(&OVERWORLD, 0, sizeof(overworld_t));
+
+  // Test
+  entityInit(OVERWORLD.entities + OVERWORLD.entityCount++, ENTITY_TYPE_PLAYER);
 }
 
 void overworldSceneInit() {
@@ -20,6 +25,8 @@ void overworldSceneDeinit() {
 }
 
 void overworldUpdate() {
-  
+  uint8_t i = 0;
+  while(i < OVERWORLD.entityCount) {
+    entityUpdate(OVERWORLD.entities + i++);
+  }
 }
-

src/dusk/overworld/overworld.h

@@ -6,7 +6,16 @@
  */
 
 #pragma once
-#include "dusk.h"
+#include "entity.h"
+
+#define OVERWORLD_ENTITY_COUNT_MAX 32
+
+typedef struct {
+  entity_t entities[OVERWORLD_ENTITY_COUNT_MAX];
+  uint8_t entityCount;
+} overworld_t;
+
+extern overworld_t overworld;
 
 void overworldInit();
 void overworldSceneInit();

src/dusk/overworld/player.c

@@ -0,0 +1,19 @@
+/**
+ * Copyright (c) 2025 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "entity.h"
+#include "assert/assert.h"
+
+void playerInit(entity_t *ent) {
+  assertNotNull(ent, "Entity cannot be NULL");
+
+  printf("Initializing player entity\n");
+}
+
+void playerUpdate(entity_t *ent) {
+  assertNotNull(ent, "Entity cannot be NULL");
+}

src/dusk/overworld/player.h

@@ -0,0 +1,29 @@
+/**
+ * Copyright (c) 2025 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#pragma once
+#include "dusk.h"
+
+typedef struct _entity_t entity_t;
+
+typedef struct {
+  int32_t nothing;
+} player_t;
+
+/**
+ * Handles initialization of the player.
+ * 
+ * @param ent The entity to initialize as a player.
+ */
+void playerInit(entity_t *ent);
+
+/**
+ * Handles updating the player.
+ * 
+ * @param ent The entity to update as a player.
+ */
+void playerUpdate(entity_t *ent);