Initial commit

src/engine/entity.c

@@ -0,0 +1,89 @@
+#include "engine/entity.h"
+#include <string.h>
+#include <stdio.h>
+
+void entity_manager_init(EntityManager *em) {
+    memset(em, 0, sizeof(EntityManager));
+}
+
+Entity *entity_spawn(EntityManager *em, EntityType type, Vec2 pos) {
+    /* Find a free slot */
+    for (int i = 0; i < MAX_ENTITIES; i++) {
+        if (!em->entities[i].active) {
+            Entity *e = &em->entities[i];
+            memset(e, 0, sizeof(Entity));
+            e->type = type;
+            e->active = true;
+            e->body.pos = pos;
+            e->body.gravity_scale = 1.0f;
+            e->health = 1;
+            e->max_health = 1;
+            if (i >= em->count) em->count = i + 1;
+            return e;
+        }
+    }
+    fprintf(stderr, "Warning: entity limit reached (%d)\n", MAX_ENTITIES);
+    return NULL;
+}
+
+void entity_destroy(EntityManager *em, Entity *e) {
+    if (!e || !e->active) return;
+
+    /* Call type-specific destructor */
+    if (em->destroy_fn[e->type]) {
+        em->destroy_fn[e->type](e);
+    }
+
+    e->active = false;
+    e->type = ENT_NONE;
+
+    /* Shrink count if possible */
+    while (em->count > 0 && !em->entities[em->count - 1].active) {
+        em->count--;
+    }
+}
+
+void entity_update_all(EntityManager *em, float dt, const Tilemap *map) {
+    for (int i = 0; i < em->count; i++) {
+        Entity *e = &em->entities[i];
+        if (!e->active) continue;
+
+        /* Check if dead */
+        if (e->health <= 0 && !(e->flags & ENTITY_INVINCIBLE)) {
+            e->flags |= ENTITY_DEAD;
+        }
+
+        /* Call type-specific update */
+        if (em->update_fn[e->type]) {
+            em->update_fn[e->type](e, dt, map);
+        }
+    }
+}
+
+void entity_render_all(EntityManager *em, const Camera *cam) {
+    for (int i = 0; i < em->count; i++) {
+        Entity *e = &em->entities[i];
+        if (!e->active) continue;
+
+        if (em->render_fn[e->type]) {
+            em->render_fn[e->type](e, cam);
+        }
+    }
+}
+
+void entity_manager_clear(EntityManager *em) {
+    for (int i = 0; i < em->count; i++) {
+        if (em->entities[i].active) {
+            entity_destroy(em, &em->entities[i]);
+        }
+    }
+    em->count = 0;
+}
+
+void entity_register(EntityManager *em, EntityType type,
+                     EntityUpdateFn update, EntityRenderFn render,
+                     EntityDestroyFn destroy) {
+    em->update_fn[type] = update;
+    em->render_fn[type] = render;
+    em->destroy_fn[type] = destroy;
+}