Pagination by category

I had a pagination for only one category “procesos”, this was the code:

<?php if(has_term('procesos', 'dslc_projects_cats')): ?>

    <?php 

        $args = array(
            'posts_per_page'  => 7,
            'post_type' => 'dslc_projects',
            'tax_query' => array('dslc_projects_cats', 'field' => 'id', 'terms' => 'procesos')
        );

        $processes = get_posts($args);
        $ids = array();

        foreach ($processes as $process) {
            $ids[] += $process->ID;
        }

        $thisindex = array_search($post->ID, $ids);

        //var_dump($ids);
        $previd = $ids[$thisindex-1];
        $nextid = $ids[$thisindex+1];

    ?>
    <div class="row">
        <div class="container inner-pagination">
            <div class="col-xs-6">
                <?php 
                    if(!empty($previd))
                        echo '<a rel="prev" href="'.get_permalink($previd).'"> &laquo; '.get_the_title($previd).'</a>';
                ?>
            </div>
            <div class="col-xs-6 text-right">
                <?php 
                    if(!empty($nextid))
                        echo '<a rel="next" href="'.get_permalink($nextid).'">'.get_the_title($nextid).' &raquo </a>';
                ?>
            </div>
        </div>
    </div>

   <?php endif; ?>

The pagination only appears in post with category “procesos”, I modified code to:

<?php 

    $args = array(
        'posts_per_page'  => 13,
        'post_type' => 'dslc_projects',

    );

    $processes = get_posts($args);
    $ids = array();
    foreach ($processes as $process) {
        $ids[] += $process->ID;
    }

    $thisindex = array_search($post->ID, $ids);

    //var_dump($ids);
    $previd = $ids[$thisindex-1];
    $nextid = $ids[$thisindex+1];
?>

The rest is the same, and now i have pagination in all the posts and is continue (without categorization): http://globalarmor.com.mx/project-view/desmontaje/

I want the pagination by category, like was before, but in all the categories (there are four). How can I achieve this?