ImageMagick

<?php

// This PHP code utilizes ImageMagick to perform image manipulation tasks similar to your Python code.
// Note that you'll need to have the Imagick extension installed and enabled in your PHP environment to run this code.
// Additionally, make sure to adjust the file paths and any other specifics according to your setup.


function map_creator($data) {
    $img = new Imagick('map_image.jpg');
    $draw = new ImagickDraw();
    $draw->setStrokeWidth(1);

    $data = str_replace("\"", "", $data);
    $data = str_replace("\'", "", $data);

    function compute_XY_from_GR($gr_east, $gr_north) {
        $base_es = 50481;
        $base_ns = 98019;
        $base_x = 644;
        $base_y = 534;

        $x = $base_x + (($gr_east - $base_es) * 0.3555);
        $y = $base_y - (($gr_north - $base_ns) * 0.355);

        $x_corr = ($y - $base_y) * 0.04;
        $x -= $x_corr;

        $y_corr = ($x - $base_x) * 0.025;
        $y += $y_corr;

        return array($x, $y);
    }

    function draw_cross($draw, $point, $pc, $age) {
        if ($pc > 20) {
            $sizer = 12;
        } elseif ($pc > 10) {
            $sizer = 9;
        } else {
            $sizer = 6;
        }

        $colors = array("rgb(0,0,255)", "rgb(255,0,255)", "rgb(255,0,0)", "rgb(255,165,0)", "rgb(255,255,0)");
        $idx = 0;
        if ($age < 2) {
            $idx = 4;
        } elseif ($age < 5) {
            $idx = 3;
        } elseif ($age < 10) {
            $idx = 2;
        } elseif ($age < 20) {
            $idx = 1;
        }

        $color = $colors[$idx];

        $draw->setStrokeColor($color);
        $draw->line($point[0] - $sizer, $point[1], $point[0] + $sizer, $point[1]);
        $draw->line($point[0], $point[1] - $sizer, $point[0], $point[1] + $sizer);
    }

    $now = time();
    $days = $now / 86400;
    $year_now = 1970 + intval($days / 365.25);

    $fsplit = explode("*", $data);
    $group = trim(array_shift($fsplit));

    $taxon = ucfirst(trim(array_shift($fsplit)));
    $vernac = ucfirst(trim(array_shift($fsplit)));   // Vernacular (Common) name
    $total = intval(trim(array_shift($fsplit)));    // Total number of sightings of this species

    $sp_refs = [];
    $griddata = $fsplit;                    // e.g. TV514989-1-2001/TV513989-7-1998/TV514990-1-2016/

    foreach ($griddata as $triple) {
        if (!$triple) {
            break;
        }
        $psplit = explode('~', $triple);
        $gr = $psplit[0];                              // get grid ref
        $gr = substr($gr, 0, 5) . "50" . substr($gr, 5) . "50"; // Adjust grid rwf to centre of 100m square
        $ctr = $psplit[1];
        $year = $psplit[2];
        $sp_refs[] = array($gr, $ctr, $year);
    }

    $more = $vernac;
    if (strtolower($vernac) === strtolower($taxon)) {  // if common name is same
        $more = $group;
    }

    $more = ucfirst($more);

    $draw->setFontSize(12);
    $draw->setFillColor("rgb(255,255,255)");
    $draw->setFont('Arial');
    $img->annotateImage($draw, 675, 40, 0, $taxon);
    $img->annotateImage($draw, 675, 80, 0, $more);
    $img->annotateImage($draw, 675, 120, 0, "$total sightings");
    $img->annotateImage($draw, 1400, 240, 0, "< 2 years");
    $img->annotateImage($draw, 1400, 270, 0, "< 5 years");
    $img->annotateImage($draw, 1400, 300, 0, "< 10 years");
    $img->annotateImage($draw, 1400, 330, 0, "< 20 years");
    $img->annotateImage($draw, 1400, 360, 0, "20 years+");

    foreach ($sp_refs as $item) {
        $gr = $item[0];                    // Grid Ref
        $ctr = $item[1];                   // Qty seen at this Grid Ref
        $year = $item[2];                  // Year of most recent sighting at this Grid Ref
        $eastings = intval(substr($gr, 2, 5));         // split numeric part of Grid Ref into Eastings and Northings
        $northings = intval(substr($gr, 7));

        $ctr = intval($ctr);                                  // Qty seen at this location
        $pc = ($ctr * 100) / $total;                          // Percent qty seen at this location compared to all locations

        list($x, $y) = compute_XY_from_GR($eastings, $northings);      // Convert Grid Ref to pixel positions X, Y

        $aged = $year_now - intval($year);                     // Age of most recent sighting at this Grid Ref

        draw_cross($draw, array($x, $y), $pc, $aged );              // Draw a cross on the map at centre of this grid ref.
    }

    $img->drawImage($draw);
    return $img;
}
?>