Dead link on the Advanced Topics page in the documentation.

[fishnet37222]

The "Advanced Topics" page in the documentation contains a link to a blog post that no longer exists. The link on the page is "Custom OpenCL functions in C++ with Boost.Compute". If you navigate to that link, you'll see it no longer exists. However, I was able to find the blog post in the Internet Archive: https://web.archive.org/web/20201112042827/http://kylelutz.blogspot.com/2014/03/custom-opencl-functions-in-c-with.html.

[ljluestc]

#include <iostream>
#include <vector>
#include <boost/compute.hpp>

namespace compute = boost::compute;

int main() {
    // Select the default OpenCL device
    compute::device device = compute::system::default_device();
    compute::context context(device);
    compute::command_queue queue(context, device);

    std::cout << "Using OpenCL device: " << device.name() << std::endl;

    // OpenCL kernel source (custom function)
    const char source[] = R"(
        __kernel void square(__global float *data) {
            int gid = get_global_id(0);
            data[gid] = data[gid] * data[gid]; // Square each element
        }
    )";

    // Build OpenCL program and create kernel
    compute::program program = compute::program::build_with_source(source, context);
    compute::kernel kernel(program, "square");

    // Create input data
    std::vector<float> host_data = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f };
    compute::vector<float> device_data(host_data.size(), context);

    // Copy data to device
    compute::copy(host_data.begin(), host_data.end(), device_data.begin(), queue);

    // Set kernel argument and execute
    kernel.set_arg(0, device_data);
    queue.enqueue_1d_range_kernel(kernel, 0, host_data.size(), 0);

    // Copy results back to host
    compute::copy(device_data.begin(), device_data.end(), host_data.begin(), queue);

    // Print results
    std::cout << "Squared Values:" << std::endl;
    for (float val : host_data) {
        std::cout << val << " ";
    }
    std::cout << std::endl;

    return 0;
}