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Further rewrite of cohesion to match separation

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This commit is contained in:
Robert Garrett
2024-07-10 14:35:46 -05:00
parent 95cdd90485
commit eb6d4b2e32
1 changed files with 12 additions and 5 deletions
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15
src/birdoids_plugin.rs
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@@ -170,6 +170,11 @@ fn cohesion(
spatial_tree: Res<KDTree2<TrackedByKdTree>>, spatial_tree: Res<KDTree2<TrackedByKdTree>>,
mut boids: Query<(&Transform, &mut Velocity), With<Boid>>, mut boids: Query<(&Transform, &mut Velocity), With<Boid>>,
) { ) {
// for each boid
// find neighbors
// find center-of-mass of neighbors
// find vector from boid to flock CoM
// apply force
for (transform, mut velocity) in &mut boids { for (transform, mut velocity) in &mut boids {
let neighbors = spatial_tree.within_distance( let neighbors = spatial_tree.within_distance(
transform.translation.xy(), transform.translation.xy(),
@@ -177,11 +182,13 @@ fn cohesion(
); );
if neighbors.len() > 0 { if neighbors.len() > 0 {
let center_of_mass = neighbors.iter() let center_of_mass = neighbors.iter()
.map(|(pos, _opt_entity)| pos ) .map(|(pos, _)| pos.extend(0.0) )
.sum::<Vec2>() / neighbors.len() as f32; .fold(transform.translation, |acc, neighbor| {
acc + neighbor
}) / (neighbors.len()) as f32;
let towards = (center_of_mass - transform.translation.xy()).normalize(); let towards = (center_of_mass - transform.translation).normalize();
**velocity += towards.extend(0.0) * COHESION_FACTOR; velocity.0 += towards * COHESION_FACTOR;
} }
} }
} }