uranix

haystack = [
    [1, 0, 0, 1, 0, 1],
    [1, 0, 1, 1, 1, 1],
    [0, 1, 0, 0, 1, 0],
    [1, 0, 1, 1, 0, 1],
    [0, 0, 0, 0, 1, 0],
    [1, 1, 1, 1, 0, 1]
]
needle = [
    [1, 0, 1],

uranix

M = 59;
h = 2 / M;

si = [];
sj = [];
sv = [];

f = zeros((M + 1) * (M + 1), 1);

lbc = @(x, y) -x;

uranix

#include <iostream>
#include <vector>
#include <functional>
#include <cmath>

template <typename T>
struct vec3 {
    T x;
    T y;
    T z;