Imported from benpm/dx12_experiments (AGENTS.md). Install upstream with npx skills add benpm/dx12_experiments. Copyright stays with the author.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Build Commands

# Requires VCPKG_ROOT env var pointing to vcpkg installation
export VCPKG_ROOT="C:/Users/ben/Documents/vcpkg"

# Configure (Ninja Multi-Config + Clang)
cmake --preset windows-clang

# Build Debug / Release
cmake --build build --config Debug
cmake --build build --config Release

# Run
./build/Debug/main.exe

Presets: windows-clang (primary), windows-msvc (fallback). Shaders compiled via DXC to .cso at build time.

Architecture

This is a from-scratch DirectX 12 rendering engine (C++23, Clang) currently rendering a colored cube with orbit camera controls.

Core classes:

• Window (singleton) — HWND creation, DXGI adapter selection, ID3D12Device2 creation, tearing support detection. Must be initialized before Application.
• Application — Owns the render loop: swap chain (triple-buffered), PSO, root signature, vertex/index buffers, depth buffer. update() handles input/camera, render() draws and presents.
• CommandQueue — Wraps ID3D12CommandQueue with fence-based CPU/GPU synchronization and command allocator pooling. Allocators are recycled when their fence value completes.
• Camera / OrbitCamera — View/projection matrix generation. OrbitCamera uses spherical coordinates (yaw, pitch, radius) driven by mouse input.
• UploadBuffer — Linear page-based allocator for GPU upload heaps. Used for one-time CPU-to-GPU data transfers.
• DescriptorAllocator (WIP) — Free-list descriptor allocation from CPU-visible heaps with RAII handles.

Math/utility types (common.hpp): vec2/3/4 (XMVECTOR wrappers), mat4 (XMMATRIX wrapper) with operator overloads. Custom literals: _deg (degrees->radians), _KB, _MB. align() for power-of-2 alignment. chkDX() macro throws on HRESULT failure.

Input uses gainput library (submodule in lib/gainput/) for keyboard, mouse, and raw input.

Rendering pipeline: Root signature uses inline 32-bit constants (MVP matrix at b0). Single draw call of 36 indices (cube). Depth testing with D32_FLOAT.

Code Style

• Chromium-based clang-format with 4-space indent, custom brace wrapping, 100 col limit
• clang-tidy enabled (bugprone, modernize, performance, readability checks)
• Windows subsystem app (no console) — use spdlog for logging (stderr + file)
• DX12 debug layer enabled in Debug builds