oxiphysics_gpu/kernels/md_force/
lennardjoneskernel_traits.rs

1//! # LennardJonesKernel - Trait Implementations
2//!
3//! This module contains trait implementations for `LennardJonesKernel`.
4//!
5//! ## Implemented Traits
6//!
7//! - `ComputeKernel`
8//!
9//! 🤖 Generated with [SplitRS](https://github.com/cool-japan/splitrs)
10use crate::compute::ComputeKernel;
11
12use super::types::LennardJonesKernel;
13
14impl ComputeKernel for LennardJonesKernel {
15    fn name(&self) -> &str {
16        "LennardJonesKernel"
17    }
18    fn execute(&self, inputs: &[&[f64]], outputs: &mut [Vec<f64>], work_size: usize) {
19        if inputs.len() < 2 || outputs.len() < 2 {
20            return;
21        }
22        let pos = inputs[0];
23        let epsilon = inputs[1][0];
24        let sigma = inputs[1][1];
25        let cutoff = inputs[1][2];
26        let n = work_size;
27        let cutoff2 = cutoff * cutoff;
28        let mut forces = vec![0.0; n * 3];
29        let mut potential = 0.0;
30        for i in 0..n {
31            let xi = [pos[i * 3], pos[i * 3 + 1], pos[i * 3 + 2]];
32            for j in (i + 1)..n {
33                let xj = [pos[j * 3], pos[j * 3 + 1], pos[j * 3 + 2]];
34                let dx = xi[0] - xj[0];
35                let dy = xi[1] - xj[1];
36                let dz = xi[2] - xj[2];
37                let r2 = dx * dx + dy * dy + dz * dz;
38                if r2 >= cutoff2 || r2 < 1e-30 {
39                    continue;
40                }
41                let r2_inv = 1.0 / r2;
42                let sr2 = sigma * sigma * r2_inv;
43                let sr6 = sr2 * sr2 * sr2;
44                let sr12 = sr6 * sr6;
45                potential += 4.0 * epsilon * (sr12 - sr6);
46                let f_mag = 24.0 * epsilon * (2.0 * sr12 - sr6) * r2_inv;
47                forces[i * 3] += f_mag * dx;
48                forces[i * 3 + 1] += f_mag * dy;
49                forces[i * 3 + 2] += f_mag * dz;
50                forces[j * 3] -= f_mag * dx;
51                forces[j * 3 + 1] -= f_mag * dy;
52                forces[j * 3 + 2] -= f_mag * dz;
53            }
54        }
55        outputs[0] = forces;
56        outputs[1] = vec![potential];
57    }
58}
oxiphysics_gpu/kernels/md_force/lennardjoneskernel_traits.rs

oxiphysics_gpu/kernels/md_force/
lennardjoneskernel_traits.rs
