Is it possible to sort/re-order a wp_query loop by a dynamic value produced from a custom field?

Question

I am trying to find ways to sort my loop from a numeric value(distance) that i can only get via a shortcode(by calculating custom field address). shortcode works, i successfully got the distance value but now i want to sort my data from closest distance to farthest.

i was trying to use usort, but i don't know how to execute it properly.

$loop = new WP_Query( $args );

function customCompare($Aint, $Bint)
{
$Aint = $distance;  
$Bint = $distance;
return ($Aint < $Bint);
} 

usort($loop->posts, 'customCompare');

while ( $loop->have_posts() ) : $loop->the_post(); 

$address = get_field('acf_address');
$distance = do_shortcode("[distance address='".$address."']");

im expecting to display my data from lowest distance value to highest but right now it doesn't do anything to my loop, just displays the default order. which means my code doesn't work. I would appreciate any help/suggestion

Answer 1

i updated my code, saved the data i needed in array and used array_multisort

$merchantPost = get_posts( $args ); 

        foreach ( $merchantPost as $post ) : 
            setup_postdata( $post ); 


            $merchant_list[] = array(
                'acf_address' => get_post_meta( $post->ID, 'acf_address', true ),
                'distance' => do_shortcode("[distance address_to='".get_field('acf_address')."']"),
                'post_title' => get_the_title(),
                'permalink' => get_the_permalink(),
                'gallery' => get_field('gallery'),
                'image' => wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'single-post-thumbnail' ),
                'terms' => get_the_terms( $post->ID, 'merchant_categories' ),
            ); 

        endforeach;

       wp_reset_postdata();


        $all_distance = array();
            foreach ( $merchant_list as $mlist ) {
                $all_distance[] = $mlist['distance'];
            }

            array_multisort($all_distance, SORT_ASC, $merchant_list, SORT_NUMERIC);

now my problem is pagination, since im not using wordpress default loop., but thats for another topic.