Lookup project demonstrating how to compute and render basic particle systems.
Implementation of a simple particle system using Swift, SwiftUI, and the Metal Shading Language. This repository serves as a knowledge archive demonstrating how to create and modify / postprocess basic particle systems. This project consists of two branches, which are described below.
The main branch contains the basic implementation of the moving particle system. It comprises a clear pass responsible for resetting the texture and a draw pass responsible for calculating and drawing the updated particle positions onto the texture. The draw pass shader also implements a very simple collision model that simulates collisions with the view boundaries. Additionally, a color selection logic has been implemented to increase the red component of each particle as it approaches the vertical view boundaries.
The following frame capture shows 1e5 particles at 60 frames per seconds:
The implement-gaussian-blur branch extends the main branch with a Gaussian blur pass, which is applied to the texture after the draw pass. Additionally, the clear pass function has been modified so that the particle trail fades out slowly.
The following frame capture shows 1e3 particles (for better visibility) at 60 frames per seconds:
Processing textures on a gpu by Apple
https://developer.apple.com/documentation/metal/compute_passes/processing_a_texture_in_a_compute_function
https://developer.apple.com/documentation/metal/textures/understanding_color-renderable_pixel_format_sizes
https://developer.apple.com/documentation/metal/textures/creating_and_sampling_textures
Underlying concept: working with particles in Metal by metalkit.org
https://metalkit.org/2017/09/30/working-with-particles-in-metal/
https://metalkit.org/2017/10/31/working-with-particles-in-metal-part-2/
https://metalkit.org/2017/11/30/working-with-particles-in-metal-part-3/