Introduction

The original motivation for this project was to learn and engage in Metal programming by building something like Shadertoy while adding additional features that I wanted to experiment with. Along the way, I discovered that the SceneKit framework has Metal integration which allows running a shader inside a SceneKit scene. Additionally, SceneKit has integration with SpriteKit to use a SpriteKit scene as a SceneKit material. And furthermore, there is integration between SpriteKit and Metal. I then pivoted to implementing an application which would let me experiment with the entire stack of graphics technologies and integration with the GPU via Metal.

This application implements a variety of scenes which replicate various GLSL shaders by using SceneKit, SpriteKit, and Metal in various combinations. In addtion to browsing and viewing these scenes, the feature that are (or will be) implemented are:

1. Support for kernel shaders and vertex shaders in addition to fragment shaders.
2. Scenes that use points or lines instead of triangles.
3. The abiity to integrate with the macOS Photo and Music libraries, to be able to use textures, photos, videos, and music stored in their native macOS applications. One should be abe to drag a photo or track from Photos or iMusic into a scene, and have that picture or audio track processed by the scene.
4. The ability to capture still frames or video sequences from a running scene directly into one's Photo library.
5. Better font handling.
6. The ability to modify parameters. XScreenSaver would generate a preferences pane from the available parameters. In this way, rather than have multiple different scenes as variants of a single scene, or #ifdefs which would modify the scene at compile time, a scene could specify parameters which woulld automatically generate a preferences pane which would allow dynamically modifying these parameters while the scene was running.

Building a scene

To be written….