cosmetics

Author: danieledapo

src/lib.rs

@@ -1,4 +1,3 @@
-use rand::seq::SliceRandom;
 use rand::Rng;
 
 pub mod geo;
@@ -24,19 +23,11 @@ impl Dla {
         attraction_radius: u16,
         seeds: impl IntoIterator<Item = Vec3>,
     ) -> Option<Self> {
-        let mut seeds = seeds.into_iter();
+        let cells: Octree = seeds.into_iter().collect();
 
-        let mut cells = Octree::new();
-
-        let first = seeds.next()?;
-        cells.add(first);
-
-        let mut bbox = Bbox::new(first);
-
-        for p in seeds {
-            cells.add(p);
-            bbox = bbox.expand(p);
-        }
+        let mut cells_it = cells.iter();
+        let first_p = cells_it.next()?;
+        let bbox = cells_it.fold(Bbox::new(*first_p), |b, p| b.expand(*p));
 
         Some(Dla {
             cells,
@@ -91,14 +82,13 @@ impl Dla {
                     break;
                 }
                 None => {
-                    let d = Vec3::new(
-                        rng.gen_range(1, self.attraction_radius / 2)
-                            * *[-1, 1].choose(rng).unwrap(),
-                        rng.gen_range(1, self.attraction_radius / 2)
-                            * *[-1, 1].choose(rng).unwrap(),
-                        rng.gen_range(1, self.attraction_radius / 2)
-                            * *[-1, 1].choose(rng).unwrap(),
-                    );
+                    let mut motion = || {
+                        let d = if rng.gen::<f32>() < 0.5 { -1 } else { 1 };
+                        rng.gen_range(1, self.attraction_radius / 2) * d
+                    };
+
+                    let d = Vec3::new(motion(), motion(), motion());
+
                     cell = cell + d * self.attraction_radius;
 
                     if !spawn_bbox.contains(cell) {

src/main.rs

@@ -9,8 +9,6 @@ use structopt::StructOpt;
 
 use dla::{Dla, Vec3};
 
-pub type Rgb = [f64; 3];
-
 /// Simulate 3D diffusion limited aggregation (DLA for short) and save the final
 /// system as a scene ready to be rendered using povray for example.
 #[derive(StructOpt, Debug)]
@@ -167,14 +165,14 @@ camera {{
     let mut cells = dla.cells().map(|cc| (cc, center.dist2(*cc))).collect::<Vec<_>>();
     cells.sort_by_key(|(_, d)| *d);
 
-    let d = cells.last().expect("empty dla, cannot happen since it should be seeded").1;
+    let max_d = cells.last().expect("empty dla, cannot happen since it should be seeded").1;
     let mut cells = cells.into_iter();
 
     let gradients = 3;
     let n = gradients * 2;
     for i in 0..n {
         writeln!(out, "\nunion {{")?;
-        for (p, _) in cells.by_ref().take_while(|(_, dd)| *dd <= (i + 1) * d / n) {
+        for (p, _) in cells.by_ref().take_while(|(_, dd)| *dd <= (i + 1) * max_d / n) {
             writeln!(out, "  sphere {{ <{}, {}, {}>, 1 }}", p.x, p.y, p.z)?;
         }
 
@@ -284,6 +282,7 @@ impl Scene {
         let scene_bbox = dla.bbox();
         let scene_dimensions = scene_bbox.dimensions();
         let away_dist = scene_dimensions.x.min(scene_dimensions.y).min(scene_dimensions.z);
+
         let camera = Camera {
             position: Vec3::new(
                 scene_bbox.center().x - away_dist,
@@ -292,8 +291,8 @@ impl Scene {
             ),
             target: Vec3::new(0, 0, 0),
         };
-        let mut lights = vec![];
 
+        let mut lights = vec![];
         let mut add_light = |pt: Vec3, intensity| {
             let position = pt + (pt - scene_bbox.center()).normalized() * away_dist;
             lights.push(Light { position, intensity })
@@ -342,6 +341,7 @@ impl Scene {
 
 impl std::str::FromStr for SceneFormat {
     type Err = String;
+
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         match s {
             "povray" => Ok(SceneFormat::Povray),

src/octree.rs

@@ -17,12 +17,6 @@ pub struct Octree {
 enum Node {
     Branch { children: Box<[Node; 8]>, bbox: Bbox },
     Leaf { points: HashSet<Vec3>, bbox: Bbox },
-    //
-    // TODO: consider adding a Full{bbox: Bbox} variant which could be constructed when we know
-    // that a bbox is completely full (remember we're living in a finite space since we're using
-    // integer coordinates). This variant would drastically improve query time and also space
-    // requirements.
-    //
 }
 
 #[derive(Debug)]
@@ -332,6 +326,12 @@ fn partition_pt(p: Vec3, c: Vec3) -> usize {
     }
 }
 
+impl Default for Octree {
+    fn default() -> Self {
+        Octree::new()
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;