lenia: optimise shader & move files

lenia-kernel/.gitignore

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+target/
+Cargo.lock

lenia-kernel/Cargo.toml

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+[package]
+name = "lenia-kernel"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

lenia-kernel/rustfmt.toml

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+hard_tabs = true

lenia-kernel/src/main.rs

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+use std::env;
+
+fn main() {
+	let args: Vec<_> = env::args().skip(1).collect();
+	if args.is_empty() {
+		println!("usage: kernel_radius");
+		return;
+	}
+	let radius = args[0].parse().unwrap();
+	let k_offset = 0.435;
+	let k_sharpness = 28.0;
+
+	let mut total_max = 0.0;
+	println!("				// generated by the rust program");
+	println!("				const int Radius = {};", radius);
+	println!("				#define RADIUS {}", radius);
+	println!("				// kernel LUT size is {} bytes", radius * (radius + 1) * 2);
+	println!("				const half Kernel[{}][{}] = {{", radius + 1, radius);
+	for y in 0..=radius {
+		print!("					{{");
+		for x in 1..=radius {
+			let k = k(x, y, radius, k_offset, k_sharpness);
+			total_max += k * 4.0;
+			print!("{:.4}, ", k);
+		}
+		println!("}},");
+	}
+	println!("				}};");
+	println!("				const float TOTAL_MAX = {};", total_max);
+}
+
+fn k(x: usize, y: usize, radius: usize, k_offset: f32, k_sharpness: f32) -> f32 {
+	let x = x as f32;
+	let y = y as f32;
+	let r = (x * x + y * y).sqrt() / radius as f32;
+	f32::exp(-((r - k_offset) * (r - k_offset)) * k_sharpness)
+	// lenia paper example kernel
+	// if r < 1.0 {
+	// 	f32::exp(4.0 - 4.0 / (4.0 * r * (1.0 - r)))
+	// } else {
+	// 	0.0
+	// }
+}