差分增长 Rust

概述

本库提供了一个非常易于使用的差分增长算法，以及使用出色的 nannou 库的示例草图。使用方法简单，只需提供起点 Vec，调用 [DifferentialGrowth::tick()] 来推进算法的一次迭代，然后使用 [DifferentialGrowth::get_points()] 获取新的状态。

通过使用内置的点生成函数，如 [generate_points_on_circle()] 生成起点，可以快速启动并运行。

建议对差分增长算法有一定的了解

• https://inconvergent.net/generative/differential-line/
• https://inconvergent.net/2016/shepherding-random-growth/

示例

了解此库的最佳方式是查看 /example 目录。您可以在任何运行 cargo run --example example 的平台上运行它。

否则，以下是如何使用此库的快速参考。

# use differential_growth::{generate_points_on_circle, DifferentialGrowth};
# use nalgebra::Point2; 
# use nannou::{event::Update, prelude::*, window, App, Frame};

// Generate a set of starting points.
// You do not have to use the included helper function,
// you could for example pass points drawn by the mouse.
let starting_points: Vec<Point2<f64>> = generate_points_on_circle(0.0, 0.0, 10.0, 10);
// Instantiate DifferentialGrowth.
// the choice of input parameters is very import to the
// succesful working of the algorithm. A value to big or too small
// or a wrong combination of values can make the algorithm behave
// like it doesn't work.
// Here I've provided values that I tested and like.
let mut dg = DifferentialGrowth::new(starting_points, 1.5, 1.0, 14.0, 1.1, 5.0);

// Advance the algorithm 1 iteration.
dg.tick();

// Get the newly calculated points.
let points_to_draw: Vec<Point2<f64>> = dg.get_points();

// draw the result by
// - drawing a line between consecutive Vec elements.
// - drawing a line between the first and the last element.

参考资料

• http://www.codeplastic.com/2017/07/22/differential-line-growth-with-processing/
• https://processing.org/examples/flocking.html
• https://inconvergent.net/2016/shepherding-random-growth/
• https://inconvergent.net/generative/differential-line/
• http://www.dgp.toronto.edu/~karan/artexhibit/mazes.pdf