Function step_columns_f64 

pub fn step_columns_f64<M>(
    model: &M,
    columns: &mut [Vec<f64>],
    n: usize,
    walls: &[WallSegment],
    params: &M::Params,
    dt: f64,
    scratch: &mut Scratch,
    peds_buf: &mut Vec<Pedestrian>,
)
where
    M: CrowdStep,

Zero-alloc SoA step over CrowdAgent columns.

Consumes parallel Vec<f64> columns in the 8-column CrowdAgent layout, runs one zero-alloc tick of model, and writes the columns back in place. peds_buf and scratch are caller-owned and reused across ticks.

This is the shape that matches rustsim::cpu_batch_step_f64’s closure signature and is the direct transliteration target for a future .cu kernel: the SoA column contract here (names, order, precision) is identical to what a CUDA launch would receive as its column pointers. On CPU today it is a thin glue layer on top of CrowdStep::step — the physics live in the model modules and are bit-exactly the same as the AoS hot path.

Example

use rustsim::cpu_batch_step_f64;
use rustsim_crowd::prelude::*;
use rustsim_crowd::integration::{step_columns_f64, SocialForceModel};
use rustsim_crowd::social_force;

let params = social_force::Params::default();
let mut scratch = Scratch::with_capacity(n, social_force::neighbor_cutoff(&params));
let mut peds_buf: Vec<Pedestrian> = Vec::with_capacity(n);
cpu_batch_step_f64::<CrowdAgent, _, _>(&store, |cols, n| {
    step_columns_f64(
        &SocialForceModel,
        cols,
        n,
        &[],
        &params,
        0.05,
        &mut scratch,
        &mut peds_buf,
    );
});