/
vectors.v
166 lines (133 loc) · 4 KB
/
vectors.v
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module main
import rand
import math
struct Vector {
x f64
y f64
z f64
}
const (
boids_count = 10000
max_coordinate = 10000.0
cohesion_distance = 10.0
separation_distance = 5.0
)
@[direct_array_access]
fn main() {
mut positions := [boids_count]Vector{}
mut velocities := [boids_count]Vector{}
for position_index in 0 .. positions.len {
positions[position_index] = Vector{
x: rand.f64() * max_coordinate
y: rand.f64() * max_coordinate
z: rand.f64() * max_coordinate
}
}
for boid_index in 0 .. positions.len {
position := positions[boid_index]
mut close_boids_ids := []int{}
for other_boid_index in 0 .. positions.len {
if boid_index == other_boid_index {
continue
}
other_position := positions[other_boid_index]
difference_x := position.x - other_position.x
difference_y := position.y - other_position.y
difference_z := position.z - other_position.z
distance := difference_x * difference_x + difference_y * difference_y +
difference_z * difference_z
if distance <= cohesion_distance * cohesion_distance {
close_boids_ids << other_boid_index
}
}
if close_boids_ids.len == 0 {
continue
}
mut cohesion := Vector{}
mut separation := Vector{}
mut separation_count := 0
mut alignment := Vector{}
for close_boid_id in close_boids_ids {
close_boid_position := positions[close_boid_id]
cohesion = Vector{
x: cohesion.x + close_boid_position.x
y: cohesion.y + close_boid_position.y
z: cohesion.z + close_boid_position.z
}
difference_from_closest := Vector{
x: position.x - close_boid_position.x
y: position.y - close_boid_position.y
z: position.z - close_boid_position.z
}
difference_magnitude := math.sqrt(
difference_from_closest.x * difference_from_closest.x +
difference_from_closest.y * difference_from_closest.y +
difference_from_closest.z * difference_from_closest.z)
if difference_magnitude <= separation_distance {
separation = Vector{
x: separation.x + difference_from_closest.x / difference_magnitude
y: separation.y + difference_from_closest.y / difference_magnitude
z: separation.z + difference_from_closest.z / difference_magnitude
}
separation_count += 1
}
close_boid_velocity := velocities[close_boid_id]
alignment = Vector{
x: alignment.x + close_boid_velocity.x
y: alignment.y + close_boid_velocity.y
z: alignment.z + close_boid_velocity.z
}
}
cohesion = Vector{
x: cohesion.x / close_boids_ids.len
y: cohesion.y / close_boids_ids.len
z: cohesion.z / close_boids_ids.len
}
cohesion_force := Vector{
x: cohesion.x - position.x
y: cohesion.y - position.y
z: cohesion.z - position.z
}
if separation_count > 0 {
separation = Vector{
x: separation.x / separation_count
y: separation.y / separation_count
z: separation.z / separation_count
}
}
alignment = Vector{
x: alignment.x / close_boids_ids.len
y: alignment.y / close_boids_ids.len
z: alignment.z / close_boids_ids.len
}
current_velocity := velocities[boid_index]
velocities[boid_index] = Vector{
x: current_velocity.x + cohesion_force.x + separation.x + alignment.x
y: current_velocity.y + cohesion_force.y + separation.y + alignment.y
z: current_velocity.z + cohesion_force.z + separation.z + alignment.z
}
}
mut position_sum := Vector{}
mut velocity_sum := Vector{}
for boid_index in 0 .. positions.len {
position := positions[boid_index]
velocity := velocities[boid_index]
positions[boid_index] = Vector{
x: position.x + velocity.x
y: position.y + velocity.y
z: position.z + velocity.z
}
position_sum = Vector{
x: position_sum.x + position.x
y: position_sum.y + position.y
z: position_sum.z + position.z
}
velocity_sum = Vector{
x: velocity_sum.x + velocity.x
y: velocity_sum.y + velocity.y
z: velocity_sum.z + velocity.z
}
}
println('${position_sum.x} - ${position_sum.y} - ${position_sum.z}')
println('${velocity_sum.x} - ${velocity_sum.y} - ${velocity_sum.z}')
}