add event queue, tower archetypes, and enemy damage. no projectiles yet

game/tower.odin

@@ -2,9 +2,32 @@ package game
 
 Tower :: struct {
 	position: Vec2,
+	kind:     Tower_Kind,
+	cooldown: f32,
 }
 
-try_place_tower :: proc(world: ^World, gx, gy: int) -> bool {
+Tower_Kind :: enum {
+	Archer,
+}
+
+Tower_Archetype :: struct {
+	kind:      Tower_Kind,
+	range:     f32,
+	damage:    int,
+	fire_rate: f32,
+	cost:      int,
+}
+
+TOWER_ARCHETYPES: [Tower_Kind]Tower_Archetype = {
+	.Archer = {kind = .Archer, range = 95, damage = 12, fire_rate = 0.45, cost = TOWER_COST},
+}
+
+get_archetype :: proc(kind: Tower_Kind) -> Tower_Archetype {
+	return TOWER_ARCHETYPES[kind]
+}
+
+try_place_tower :: proc(world: ^World, gx, gy: int, kind: Tower_Kind) -> bool {
+	arch := get_archetype(kind)
 	if !can_build_at(&world.world_map, gx, gy) do return false
 	if world.gold < TOWER_COST do return false
 
@@ -13,8 +36,48 @@ try_place_tower :: proc(world: ^World, gx, gy: int) -> bool {
 		if distance(t.position, pos) < 1 do return false
 	}
 
-	world.gold -= TOWER_COST
-	append(&world.towers, Tower{position = pos})
+	world.gold -= arch.cost
+	append(&world.towers, Tower{position = pos, kind = kind, cooldown = 0})
 	return true
 }
 
+find_target :: proc(tower: Tower, world: ^World) -> ^Enemy {
+	arch := get_archetype(tower.kind)
+	best: ^Enemy = nil
+	best_dist: f32 = 999999
+
+	for i in 0 ..< MAX_ENEMIES {
+		e := &world.enemies[i]
+
+		if !e.active do continue
+
+		d := distance(tower.position, e.position)
+		if d <= arch.range && d < best_dist {
+			best = e
+			best_dist = d
+		}
+	}
+	return best
+}
+
+update_towers :: proc(world: ^World, dt: f32) {
+	for i in 0 ..< len(world.towers) {
+		t := &world.towers[i]
+		t.cooldown -= dt
+
+		if t.cooldown > 0 do continue
+
+		target := find_target(t^, world)
+		if target == nil do continue
+
+		arch := get_archetype(t.kind)
+		target.health -= arch.damage
+		t.cooldown = arch.fire_rate
+
+		if target.health <= 0 {
+			target.active = false
+			push_event(world, .Enemy_Killed, gold_reward = 5)
+		}
+	}
+}
+