/MetalRT

Ray tracing with Metal.

Primary LanguageSwift

MetalRT

Ray tracing with Metal. A lab to explore various ray tracing implementations with Metal.

Usage

  • Setup new app in Swift Playgrounds 4
  • Delete *.swift files
  • Delete predefined *.swift files in app
  • Add shader.msl files with SP4 as resource
  • Run app

Result

triangle

Tools

Apps used on iPad

Apps used on Winos 10

Setup

  • Install Cygwin with development tools (for what it's good for)

  • Install Swift on Windows (according to Traditional Installation section)

  • Create repository on GitHub (default settings)

  • Clone repository from GitHub

    Cygwin command prompt (bash)

    git clone https://github.com/otabuzzman/MetalRT
# use SSH (optional)
# git clone git://github.com/otabuzzman/MetalRT

cd MetalRT

  • Create SSH keys (optional)

    ssh-keygen -t ed25519 -C iuergen.schuck@gmail.com -f ~/.ssh/github.com.MetalRT
chmod 400 ~/.ssh/github.com.MetalRT

  • Swift package initialization

    Winos command prompt (CMD)

    cd MetalRT

swift package init

rem check
swift build

  • Sync package with GitHub

    Cygwin command prompt (bash)

    # enable SSH key usage for session
# eval "$(ssh-agent -s)"
# ssh-add ~/.ssh/github.com.MetalRT

git add -A
git push origin main

# tag required to load package with SP4
git tag -a 0.1.0 -m 'initial commit'
git push origin 0.1.0

Which file for what

File Comment
CUIView.swift A SwiftUI wrapper for custom UIViews.
MUIView.swift A custom MTKView.
MUIRenderer.swift A boilerplate renderer to be used with MUIView.
MHWRenderer.swift A Hello World renderer sub-classed from MUIRenderer.
Wavefront.swift A class to read a Wavefront OBJ file.
XPU.swift Types shared between CPU and GPU.
Exception.swift Error exceptions.
Extension.swift SwiftUI classes and protocols extensions.
shader.msl Simple pass-through vertex and fragment shader functions.

Findings

  • No .metal file support in SP4. Metal Shader Language (MSL) code via String class in Swift source files (e.g. ending on .metal.swift) ok for SP4 playgrounds and apps. The latter allows MSL files as resources. File suffixes must have three characters (e.g. .msl). Otherwise (e.g. when using .metal suffix) SP4 will report an unknown resource error on app open.
  • Removing resource files only make them disappear in file system but app still works as if they remain present.