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Use cache to significantly reduce vert count

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This commit is contained in:
Tyler Hallada
2019-04-07 02:11:23 -04:00
parent ebc9fdfdb2
commit c5044a3a4f
8 changed files with 50 additions and 62 deletions
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98
src/main.rs
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@@ -10,6 +10,8 @@ use cgmath::Vector3;
use serde::ser::{SerializeSeq, Serializer};
use serde::Serialize;
const VERT_CACHE_PRECISION: f32 = 10000_f32;
#[derive(Debug)]
struct Triangle {
a: usize,
@@ -44,6 +46,8 @@ struct ArraySerializedVector(Vector3<f32>);
struct Polyhedron {
positions: Vec<ArraySerializedVector>,
cells: Vec<Triangle>,
#[serde(skip)]
added_vert_cache: HashMap<(i32, i32, i32), usize>,
}
impl Serialize for ArraySerializedVector {
@@ -65,26 +69,14 @@ impl Polyhedron {
Polyhedron {
positions: vec![],
cells: vec![],
added_vert_cache: HashMap::new(),
}
}
fn new_isocahedron(radius: f32, detail: usize) -> Polyhedron {
let t = (1.0 + (5.0 as f32).sqrt()) / 2.0;
let base_isocahedron = Polyhedron {
positions: vec![
ArraySerializedVector(Vector3::new(-1.0, t, 0.0)),
ArraySerializedVector(Vector3::new(1.0, t, 0.0)),
ArraySerializedVector(Vector3::new(-1.0, -t, 0.0)),
ArraySerializedVector(Vector3::new(1.0, -t, 0.0)),
ArraySerializedVector(Vector3::new(0.0, -1.0, t)),
ArraySerializedVector(Vector3::new(0.0, 1.0, t)),
ArraySerializedVector(Vector3::new(0.0, -1.0, -t)),
ArraySerializedVector(Vector3::new(0.0, 1.0, -t)),
ArraySerializedVector(Vector3::new(t, 0.0, -1.0)),
ArraySerializedVector(Vector3::new(t, 0.0, 1.0)),
ArraySerializedVector(Vector3::new(-t, 0.0, -1.0)),
ArraySerializedVector(Vector3::new(-t, 0.0, 1.0)),
],
let mut base_isocahedron = Polyhedron {
positions: vec![],
cells: vec![
Triangle::new(0, 11, 5),
Triangle::new(0, 5, 1),
@@ -107,7 +99,21 @@ impl Polyhedron {
Triangle::new(8, 6, 7),
Triangle::new(9, 8, 1),
],
added_vert_cache: HashMap::new(),
};
base_isocahedron.add_position(Vector3::new(-1.0, t, 0.0));
base_isocahedron.add_position(Vector3::new(1.0, t, 0.0));
base_isocahedron.add_position(Vector3::new(-1.0, -t, 0.0));
base_isocahedron.add_position(Vector3::new(1.0, -t, 0.0));
base_isocahedron.add_position(Vector3::new(0.0, -1.0, t));
base_isocahedron.add_position(Vector3::new(0.0, 1.0, t));
base_isocahedron.add_position(Vector3::new(0.0, -1.0, -t));
base_isocahedron.add_position(Vector3::new(0.0, 1.0, -t));
base_isocahedron.add_position(Vector3::new(t, 0.0, -1.0));
base_isocahedron.add_position(Vector3::new(t, 0.0, 1.0));
base_isocahedron.add_position(Vector3::new(-t, 0.0, -1.0));
base_isocahedron.add_position(Vector3::new(-t, 0.0, 1.0));
let mut subdivided = Polyhedron::new();
subdivided.subdivide(base_isocahedron, radius, detail);
subdivided
@@ -121,14 +127,11 @@ impl Polyhedron {
}
fn subdivide(&mut self, other: Polyhedron, radius: f32, detail: usize) {
// TODO: maybe make this part of the polygon stuct to avoid having to pass it around
let mut added_vert_cache: HashMap<(i32, i32, i32), usize> = HashMap::new();
let precision = 10_f32.powi(4);
for triangle in other.cells {
let a = other.positions[triangle.a].0;
let b = other.positions[triangle.b].0;
let c = other.positions[triangle.c].0;
self.subdivide_triangle(a, b, c, radius, detail, precision, &mut added_vert_cache);
self.subdivide_triangle(a, b, c, radius, detail);
}
}
@@ -139,8 +142,6 @@ impl Polyhedron {
c: Vector3<f32>,
radius: f32,
detail: usize,
precision: f32,
added_vert_cache: &mut HashMap<(i32, i32, i32), usize>,
) {
let cols = 2usize.pow(detail as u32);
let mut new_vertices: Vec<Vec<Vector3<f32>>> = vec![];
@@ -167,18 +168,13 @@ impl Polyhedron {
let mut triangle = Triangle { a: 0, b: 0, c: 0 };
if j % 2 == 0 {
triangle.a =
self.add_position(new_vertices[i][k + 1], precision, added_vert_cache);
triangle.b =
self.add_position(new_vertices[i + 1][k], precision, added_vert_cache);
triangle.c = self.add_position(new_vertices[i][k], precision, added_vert_cache);
triangle.a = self.add_position(new_vertices[i][k + 1]);
triangle.b = self.add_position(new_vertices[i + 1][k]);
triangle.c = self.add_position(new_vertices[i][k]);
} else {
triangle.a =
self.add_position(new_vertices[i][k + 1], precision, added_vert_cache);
triangle.b =
self.add_position(new_vertices[i + 1][k + 1], precision, added_vert_cache);
triangle.c =
self.add_position(new_vertices[i + 1][k], precision, added_vert_cache);
triangle.a = self.add_position(new_vertices[i][k + 1]);
triangle.b = self.add_position(new_vertices[i + 1][k + 1]);
triangle.c = self.add_position(new_vertices[i + 1][k]);
}
self.cells.push(triangle);
@@ -189,20 +185,18 @@ impl Polyhedron {
fn add_position(
&mut self,
vertex: Vector3<f32>,
precision: f32,
added_vert_cache: &mut HashMap<(i32, i32, i32), usize>,
) -> usize {
let vertex_key = (
(vertex.x * precision).round() as i32,
(vertex.y * precision).round() as i32,
(vertex.z * precision).round() as i32,
(vertex.x * VERT_CACHE_PRECISION).round() as i32,
(vertex.y * VERT_CACHE_PRECISION).round() as i32,
(vertex.z * VERT_CACHE_PRECISION).round() as i32,
);
if let Some(added_vert_index) = added_vert_cache.get(&vertex_key) {
if let Some(added_vert_index) = self.added_vert_cache.get(&vertex_key) {
return *added_vert_index;
} else {
self.positions.push(ArraySerializedVector(vertex));
let added_index = self.positions.len() - 1;
added_vert_cache.insert(vertex_key, added_index);
self.added_vert_cache.insert(vertex_key, added_index);
return added_index;
}
}
@@ -248,26 +242,20 @@ impl Polyhedron {
&mut mid_centroid_cache,
);
let positions_start = self.positions.len();
// TODO: remove duplication here:
// push all triangle_centroids at beginning, same index as face_index
// push center_point once in outer loop and save index
// (is it okay if vertices show up in positions out of order like that?)
// -- yes, I think it is okay
self.positions.push(ArraySerializedVector(center_point));
self.positions.push(ArraySerializedVector(centroid));
self.positions.push(ArraySerializedVector(mid_b_centroid));
self.positions.push(ArraySerializedVector(mid_c_centroid));
let center_point_index = self.add_position(center_point);
let centroid_index = self.add_position(centroid);
let mid_b_centroid_index = self.add_position(mid_b_centroid);
let mid_c_centroid_index = self.add_position(mid_c_centroid);
self.cells.push(Triangle::new(
positions_start,
positions_start + 1,
positions_start + 2,
center_point_index,
centroid_index,
mid_b_centroid_index,
));
self.cells.push(Triangle::new(
positions_start,
positions_start + 1,
positions_start + 3,
center_point_index,
centroid_index,
mid_c_centroid_index,
));
}
}