From 0e4e49b94024ae8be96a81327dadbe868ff123ab Mon Sep 17 00:00:00 2001
From: Alex Ilchenko <ilczenko@gmail.com>
Date: Wed, 6 Mar 2024 16:41:14 +0100
Subject: [PATCH] feat(engine): added getShouldUpdate function

---
 .../get-should-update/get-should-update.ts    | 28 +++++++++++++++++++
 .../engine/utils/get-should-update/index.ts   |  1 +
 2 files changed, 29 insertions(+)
 create mode 100644 src/features/engine/utils/get-should-update/get-should-update.ts
 create mode 100644 src/features/engine/utils/get-should-update/index.ts

diff --git a/src/features/engine/utils/get-should-update/get-should-update.ts b/src/features/engine/utils/get-should-update/get-should-update.ts
new file mode 100644
index 0000000..beb2284
--- /dev/null
+++ b/src/features/engine/utils/get-should-update/get-should-update.ts
@@ -0,0 +1,28 @@
+import { Entity, isMovable } from '../../types/entities';
+import { getIsSameVector } from '../get-is-same-vector';
+
+export const getShouldUpdate = ({
+	entities,
+	previousEntities,
+}: {
+	entities: Entity[];
+	previousEntities: Entity[];
+}): boolean => {
+	if (previousEntities.length !== entities.length) return true;
+
+	const movables = entities.filter(isMovable);
+	const previousMovables = previousEntities.filter(isMovable);
+
+	return movables.some((entity) => {
+		const previousEntity = previousMovables.find(
+			(current) => current.id === entity.id,
+		);
+
+		if (!previousEntity) return true;
+
+		return (
+			!getIsSameVector(entity.position, previousEntity.position) ||
+			!getIsSameVector(entity.velocity, previousEntity.velocity)
+		);
+	});
+};
diff --git a/src/features/engine/utils/get-should-update/index.ts b/src/features/engine/utils/get-should-update/index.ts
new file mode 100644
index 0000000..eab1581
--- /dev/null
+++ b/src/features/engine/utils/get-should-update/index.ts
@@ -0,0 +1 @@
+export * from './get-should-update';