bspeice
7adb747625
All shader-related code has been removed; GPU entry points will be added once there's a better understanding of how the API should work.
87 lines
3.2 KiB
Rust
87 lines
3.2 KiB
Rust
//! # Sierpinski Gasket
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//!
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//! The Sierpinski Gasket is a simple iterated function system (IFS) that demonstrates
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//! the basic principles of using the "chaos game" to generate images. Using a set of three
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//! transforms, generate new points in the function system using the chaos game,
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//! then plot those points and display the resulting image.
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use anyhow::{Context, Result};
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use enkou_shaders::Coefficients2;
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use enkou_shaders::camera::Camera;
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use enkou_shaders::chaos_game::ChaosGame;
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use enkou_shaders::transform::Transform;
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use enkou_shaders::variation::Variation;
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use glam::{Affine2, UVec2, Vec2, uvec2};
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use image::{GrayImage, Luma};
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use rand::SeedableRng;
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use rand_xoshiro::Xoshiro256StarStar;
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use std::mem;
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use std::process::Command;
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use tempfile::NamedTempFile;
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const ITERATIONS_DISCARD: usize = 20;
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const IMAGE_DIMENSION: UVec2 = uvec2(600, 600);
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const IMAGE_QUALITY: f32 = 1.0;
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/// Build and display a simple fractal - the Sierpinski Gasket
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pub fn main() -> Result<()> {
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let mut rng = Xoshiro256StarStar::from_seed([4u8; 32]);
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let transforms = [
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{
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// F_0: (x / 2, y / 2)
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let coefficients = Affine2::from_coefficients(0.5, 0.0, 0.0, 0.0, 0.5, 0.0);
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Transform::new(coefficients, Affine2::IDENTITY, uvec2(0, 1), 0.0, 0.5)
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},
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{
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// F_1: ((x + 1) / 2, y / 2)
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let coefficients = Affine2::from_coefficients(0.5, 0.0, 0.5, 0.0, 0.5, 0.0);
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Transform::new(coefficients, Affine2::IDENTITY, uvec2(0, 1), 0.5, 0.5)
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},
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{
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// F_2: (x / 2, (y + 1) / 2)
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let coefficients = Affine2::from_coefficients(0.5, 0.0, 0.0, 0.0, 0.5, 0.5);
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Transform::new(coefficients, Affine2::IDENTITY, uvec2(0, 1), 1.0, 0.5)
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},
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];
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let weights = [1.0 / 3.0, 1.0 / 3.0, 1.0 / 3.0];
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let variations = [Variation::IDENTITY];
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// The gasket is defined on the range [0, 1] for both X and Y
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let camera = Camera::new(
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IMAGE_DIMENSION,
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Vec2::ONE * 0.5,
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0.0,
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Vec2::ZERO,
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IMAGE_DIMENSION.as_vec2(),
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);
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let mut image = GrayImage::new(IMAGE_DIMENSION.x, IMAGE_DIMENSION.y);
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let chaos_game = ChaosGame::new(&mut rng, &transforms, &weights, &variations);
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let iterations = (IMAGE_DIMENSION.element_product() as f32 * IMAGE_QUALITY) as usize;
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chaos_game
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.skip(ITERATIONS_DISCARD)
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.take(iterations)
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.for_each(|(ifs_point, _)| {
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if let Some(pixel_point) = camera.transform_point_to_image(ifs_point) {
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image.put_pixel(pixel_point.x, pixel_point.y, Luma([255u8]));
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}
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});
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let temp = NamedTempFile::with_suffix(".png").context("Unable to create file for image")?;
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image.save(temp.path()).context("Unable to save image")?;
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let mut command = cfg_select! {
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unix => Command::new("xdg-open").arg(temp.path()).spawn(),
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windows => Command::new("PowerShell").arg("-Command").arg(format!("start {}", temp.path().display())).spawn(),
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_ => Err(anyhow::anyhow!("No available program to open images"))?
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}?;
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command.wait()?;
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// In case the image viewer forks and gives control back prior to reading the file,
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// drop it and don't run the destructor
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mem::forget(temp);
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Ok(())
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}
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