Translating To Metal4 Api

---
name: translating-to-metal4-api
description: ALWAYS use as the Metal 4 API reference and cross-API translation map when porting graphics code to Metal 4 — translating Metal 3, D3D12, or Vulkan calls, looking up any MTL4 / Metal 4 API or renamed type, finding the Metal 4 equivalent of a source-API call, or learning what the redesign removed or changed. Covers the Metal 3 → Metal 4 namespace/type table, removed/changed APIs (ParallelRenderEncoder, set*Bytes), Apple GPU TBDR (tile-based deferred rendering) architecture, and the D3D12 / Vulkan / Metal 3 → Metal 4 translation tables. Do NOT trigger for buffer/texture/heap/residency/storage-mode management — use `managing-metal4-resources`; barriers, fences, or events — use `managing-metal4-synchronization`; pipeline state creation, MTL4Compiler, or reflection — use `creating-metal4-shader-pipelines`; CAMetalLayer drawable presentation — use `presenting-metal-drawables`.
---

# Metal 4 API Reference

## Overview

Metal 4 is a ground-up API redesign — not a minor version bump. It introduces the `MTL4` prefix (ObjC protocols/classes) / `MTL4::` namespace (metal-cpp). All Metal 4 objects are created from `MTLDevice` / `MTL::Device`. Key removals: blit encoder, parallel render encoder, set*Bytes, managed storage mode, per-encoder resource binding, addCompletedHandler.

Metal 4 requires macOS 26+, iOS 26+. Feature detection:

```objc
// ObjC
if ([device supportsFamily:MTLGPUFamilyMetal4]) { /* Metal 4 path */ }
```
```cpp
// metal-cpp
if (device->supportsFamily(MTL::GPUFamilyMetal4)) { /* Metal 4 path */ }
```

Metal 4 can coexist with Metal 3 queues in the same app for incremental adoption.

## Apple GPU Architecture: TBDR