A proof-of-concept for rendering Metal graphics inside a SwiftUI
View, including support for Xcode Previews. Built on top of
MetalUI (included as a
local package in this repository).
While intended to stay minimal, BasicSurfaces also demonstrates:
- Debugging and instrumentation using Apple's tools (
OSLog,OSSignposter) - DocC documentation (build via Product > Build Documentation in Xcode)
If you are interested in seeing what can be built on top of BasicSurfaces, check out my app Surfaces, available on Apple's App Store.
BasicSurfaces should be git clone-able and build right out of
the box. It builds for macOS, iOS, and iPadOS. You may need to alter
build settings to enable Mac Catalyst or adjust older OS
compatibility. This should work for any device that can run SwiftUI.
v0.1 of BasicSurfaces is much more bare bones. It has everything
needed to get up and running, but lacks documentation and lacks usage
of e.g. OSLog. I added these in v0.2 of BasicSurfaces so that
someone just getting started can have a little more to chew on.
If you find a build bug — or any kind of bug — please let me know via GitHub issues or email.
- Opening
Basic3DView.swiftin Xcode shows a multicolored rotating sphere in the Xcode Preview canvas - Building and running the app displays the same rotating sphere, rendered at a constant 60 fps
- The sphere has depth / depth buffering is enabled
- In the bottom right of the screen there are two buttons, described in detail below
The app includes a toggle button that switches between CPU and GPU sphere vertex generation at runtime. A small label in the bottom-right corner shows which method is active.
- CPU: Uses
Sphere.init(device:), which generates vertices on the CPU and should always succeed. - GPU: Uses
Sphere.init?(device:radius:vertexCount:), which generates vertices via a Metal compute shader. If GPU generation fails, the app falls back to CPU automatically.
In both cases, generation time is logged to the console.
The app includes a toggle button (bottom-right corner) that enables a brightness animation, pulsing the sphere's brightness between 0.0 and 1.0 over time using the fragment shader's brightness uniform.
Full API documentation can be built in Xcode via Product > Build Documentation. The DocC catalog covers all public types, the rendering pipeline, surface geometry, and the linear algebra utilities.