MODX Revo snippet to divide resources into columns.

how to use

Call the snippet

[[multiCols?
&cols=`2`
&tvs=`{"image":1}`
&select=`pagetitle,introtext`
&where=`{"published":1, "deleted":0, "parent":2}`
&sortby=`publishedon`
&sortdir=`DESC`
&tpl=`tpl_article`
]]

And call columns. For example for 2-columned output it will be: [[+column1]] and [[+column2]]

Attention: you need to explicitly specify basePath for tvs with not default media source.

TV with name image will be available in tpl as [[+image]].

modx_multiColumns

<?php
// move it to snippet parameters
$cols = 2;
$limit = 0;
$sortby = 'menuindex';
$sortdir = 'ASC';

//snippet start
$c = $modx->newQuery('modResource');

// init select array

if (isset($select)){
    $select = explode(',',$select);
    $select[] = 'modResource.id as id';
}
else{
    $select = array('modResource.id', 'modResource.pagetitle', 'modResource.longtitle', 'modResource.publishedon'
    ,'modResource.alias','modResource.content','modResource.introtext');
}

//process tvs

if (isset($tvs)){
    $tvs = json_decode($tvs,1);
}
else{
    $tvs = array();
}
foreach ($tvs as $name=>$id){
    $alias = 'tv_'.$name;
    $c->leftJoin('modTemplateVarResource',$alias
    , array($alias.'.contentid=modResource.id', $alias.'.tmplvarid' => $id));
    $select[] = $alias.'.value as '.$name;
}

// where condition

if (!isset($where)){
    $where = array('modResource.published' => 1, 'modResource.deleted' => 0); 
}
else{
    $where = json_decode($where,1);
}

//query

$c->where($where);
$c->select($select);
$c->sortby($sortby, $sortdir);
$c->limit($limit);
$collections = array();
if ($c->prepare() && $c->stmt->execute()) {
    $collections = $c->stmt->fetchAll(PDO::FETCH_ASSOC);
}

//generate collumns

$n = count($collections);
$delta = floor($n/$cols);
$columns = array();
for ($i=0; $i < $cols; $i++){
    $output = '';
    //$output .= '<br/>col:'.($i+1).'<br/>';
    $offset = $i*$delta;
    if ($i == $cols-1){
        $to = $n;
    }
    else{
        $to = $offset + $delta;
    }
    for ($j=$offset; $j < $to; $j++){
        if (!isset($tpl)){
            $output .= '<pre>'. print_r($collections[$j],1)  .'</pre>';
        }
        else{
            $output .= $modx->getChunk($tpl, $collections[$j]);
        }
    }
    $columns['column'.($i+1)] = $output;
}
$modx->setPlaceholders($columns);
return;