Factored out crates for web version

mandelia_renderer/src/lib.rs

@@ -0,0 +1,111 @@
+//#![feature(portable_simd)]
+
+use clap::Parser;
+use image::{ImageBuffer, Rgb};
+use std::path::PathBuf;
+
+pub mod transform;
+
+#[derive(Parser)]
+pub struct Args {
+    #[clap(short, long, default_value_t = 3840)]
+    pub width: u32,
+    #[clap(short, long, default_value_t = 2160)]
+    pub height: u32,
+
+    #[clap(short, long, default_value_t = 100)]
+    pub maxiter: usize,
+
+    #[clap(short, long, default_value="out.png")]
+    pub output: PathBuf,
+
+    pub transform: Vec<String>
+}
+
+pub type Float = f64;
+pub type Point = Complex<Float>;
+use num::complex::Complex;
+pub type Transform = [(Point, Point); 3];
+
+trait ComplexExt<T> {
+    fn norm2(self) -> T;
+}
+
+impl ComplexExt<Float> for Complex<Float> {
+    fn norm2(self) -> Float {
+        self.im * self.im + self.re * self.re
+    }
+}
+
+fn transform_point(transform: &Transform, point: Point) -> (Point, Point) {
+    let start = transform[0].0 * point.re + transform[1].0 * point.im + transform[2].0;
+    let delta = transform[0].1 * point.re + transform[1].1 * point.im + transform[2].1;
+    (start, delta)
+}
+
+pub struct Config {
+    pub transform: Transform,
+    pub width: u32,
+    pub height: u32,
+    pub maxiter: usize,
+    // We represent escape as the square of its magnitude
+}
+
+
+
+impl Config {
+    fn render_point(&self, (base, delta): (Point, Point)) -> Float {
+        const ESCAPE: Float = 2.;
+        const ESCAPE2: Float = ESCAPE * ESCAPE;
+
+        let result  =
+            std::iter::successors(Some(base), |i| Some(*i * *i + delta))
+                .take(self.maxiter)
+                .enumerate()
+                .skip_while(|(_, i)| i.norm2() <= ESCAPE2)
+                .next()
+                .map_or(0.,
+                        |(iter, val)|
+                            iter as Float + 1. - val.norm().ln().ln() / ESCAPE.ln()
+                            );
+        result as Float
+    }
+
+    pub fn render_image(&self) -> ImageBuffer<Rgb<u8>, Vec<u8>> {
+        let scale = 2.0 / std::cmp::min(self.width, self.height) as Float;
+
+        ImageBuffer::<image::Rgb<u8>, _>::from_par_fn(self.width, self.height, |x, y| {
+            let x = (x as Float) * scale - 1.;
+            let y = (y as Float) * scale - 1.;
+            let point = transform_point(&self.transform, Complex::new(x, y));
+            map_palette(self.render_point(point) / self.maxiter as Float)
+        })
+    }
+}
+
+pub fn map_palette(val: Float) -> image::Rgb<u8> {
+    let magnitude = Float::clamp(val * 255., 0., 255.) as u8;
+    image::Rgb([magnitude, magnitude, magnitude])
+}
+pub fn main() -> anyhow::Result<()> {
+
+    // let transform = [
+    //     (Point::new(0., 0.), Point::new(1., 0.)),
+    //     (Point::new(0., 0.), Point::new(0., 1.)),
+    //     (Point::new(0., 0.), Point::new(0., 0.)),
+    // ];
+
+    let args = <Args as clap::Parser>::parse();
+
+    let config = Config {
+        transform: transform::parse_transforms(args.transform.iter())?,
+        width: args.width,
+        height: args.height,
+        maxiter: args.maxiter,
+    };
+
+    let img = config.render_image();
+
+    img.save(&args.output)?;
+    Ok(())
+}

mandelia_renderer/src/transform.rs

@@ -0,0 +1,130 @@
+use num::Num;
+use super::{Float, Point};
+pub type MTransform = nalgebra::Matrix5<Float>;
+
+#[derive(Debug)]
+pub enum Type {
+    Rotation(u8, u8, Float),
+    Translation(u8, Float),
+    CoordSwap(u8, u8),
+    Scale(Float),
+}
+
+impl From<Type> for MTransform {
+    fn from(ty: Type) -> Self {
+        match ty {
+            Type::Rotation(a0, a1, _) if a0 == a1=> MTransform::identity(),
+            Type::Rotation(a0, a1, delta) => {
+                let a0 = a0 as usize;
+                let a1 = a1 as usize;
+                let delta = delta.to_radians();
+                let s = delta.sin();
+                let c = delta.cos();
+                let mut m = MTransform::identity();
+                m[(a0,a0)] = c;
+                m[(a0,a1)] = -s;
+                m[(a1,a0)] = s;
+                m[(a1,a1)] = c;
+                m
+            }
+            Type::Translation(a, delta) => {
+                let mut m = MTransform::identity();
+                m[(4, a as usize)] = -delta;
+                m
+            }
+            Type::CoordSwap(a, b) => {
+                let mut m = MTransform::identity();
+                let a = a as usize;
+                let b = b as usize;
+                m[(a,a)] = 0.;
+                m[(b,b)] = 0.;
+                m[(a,b)] = 1.;
+                m[(b,a)] = 1.;
+                m
+            }
+            Type::Scale(delta) => {
+                let mut xf = MTransform::identity() / delta;
+                xf[(4,4)] = 1.;
+                xf
+            }
+        }
+    }
+}
+fn parse_axis(c: char) -> Option<u8> {
+    Some(match c {
+        'x' => 0,
+        'y' => 1,
+        'X' => 2,
+        'Y' => 3,
+        _ => return None,
+    })
+}
+
+/// We take a type and distance.
+/// We have four axes, x,y,X,Y. The first two adjust the base point; the second two adjust the delta.
+///
+/// Given that, a plane can be defined with two axes, and a translation can be defined with one.
+/// 
+/// TODO: replace this with a nom parser
+pub fn parse_step(s: &str) -> Option<Type> {
+    if let Some(r) = s.strip_prefix("z") {
+        return Float::from_str_radix(r, 10).ok().map(Type::Scale);
+    }
+    if s.len() < 2 {
+        return None;
+    }
+    let mut chars = s.chars();
+    let axis0 = chars.next().and_then(parse_axis)?;
+    Some(match chars.clone().next()? {
+        '=' => {
+            chars.next();
+            let axis1 = chars.next().and_then(parse_axis)?;
+            Type::CoordSwap(axis0, axis1)
+        }
+        'x' | 'X' | 'y' | 'Y' => {
+            chars.next();
+            let axis1 = chars.next().and_then(parse_axis)?;
+            if axis0 == axis1 {
+                return None;
+            }
+            let val = Float::from_str_radix(chars.as_str().trim(), 10).ok()?;
+            Type::Rotation(axis0, axis1, val)
+        }
+        '0' ..= '9' => {
+            let val = Float::from_str_radix(chars.as_str().trim(), 10).ok()?;
+            Type::Translation(axis0, val)
+        }
+        _ => return None,
+    })
+}
+
+pub fn transform_to_coords(mat: &MTransform) -> super::Transform {
+    let bx = Point::new(mat[(0,0)], mat[(0,1)]);
+    let by = Point::new(mat[(1,0)], mat[(1,1)]);
+    let bd = Point::new(mat[(4,0)], mat[(4,1)]);
+
+    let cx = Point::new(mat[(0,2)], mat[(0,3)]);
+    let cy = Point::new(mat[(1,2)], mat[(1,3)]);
+    let cd = Point::new(mat[(4,2)], mat[(4,3)]);
+    [
+        (bx, cx),
+        (by, cy),
+        (bd, cd),
+    ]    
+}
+
+pub fn parse_transforms<'a>(transforms: impl Iterator<Item=impl AsRef<str>>) ->anyhow::Result<super::Transform> {
+    let mat = transforms
+        .map(|s| parse_step(s.as_ref())
+            .ok_or_else(|| anyhow::anyhow!("Invalid step: {:?}", s.as_ref())))
+            .try_fold(MTransform::identity(),
+                      |acc, new| new.map(|new| acc * MTransform::from(new)))?;
+
+
+    Ok(transform_to_coords(&mat))
+
+}
+
+pub fn parse_transform(s: &str) -> anyhow::Result<super::Transform> {
+    parse_transforms(s.split_whitespace())
+}