Не получается вывести график php

Нужно построить график в php, не используя библиотеки. Данные берутся с БД. Наклепал свой говнокод еле живой, но никак не могу понять, как вывести график. Прошу о помощи.

<?php
    $dollar = $_GET['dollar'];
    $euro = $_GET['euro'];
    $pound = $_GET['pound'];
    $year = $_GET['year'];
    $number = $_GET['number'];

    $username = "mysql";
    $password = "mysql";
    $dbName = "lab10";

    $mysqli = new mysqli("localhost", $username, $password, $dbName);
    if(mysqli_connect_errno()){
        printf(nl2br("Ошибка соединения: %s\n"), mysqli_connect_error());
        exit();
    }

    if(!$mysqli->set_charset("utf8")){
        printf(nl2br("Ошибка кодировки"), $mysqli->error);
        exit();
    }


    $fontFile = "C:\Windows\Fonts\arial.ttf";

    if (($dollar == 0) && ($euro == 0) && ($pound == 0)) {
            header("Content-Type: image/jpeg");
            $imH = 700;
            $imW = 900;
            $im = ImageCreate($imW, $imH);
            $bgcolor = ImageColorAllocate($im,255,255,200);

            $textColor = ImageColorAllocate($im,0,0,0);
            imagettftext($im, 30, 0, 350, 270, $textColor, $fontFile, "Ошибка");
            imagettftext($im, 30, 0, 130, 330, $textColor, $fontFile, "По данному запросу данных нет!");

            imagepng($im);
     }

    else{
        $dollar_data = array();
        $euro_data = array();
        $pound_data = array();
        $values = array();
        $dates = array();

        $query = "SELECT CDate, dollar, euro, GBP FROM tcurrency WHERE YEAR(CDate) = '$year'";

            $res = $mysqli->query($query);
            $row = $res->fetch_row();
            $check_number = mysqli_num_rows($res);


        if($result = $mysqli->query($query))
            while($row = $result->fetch_array(MYSQLI_ASSOC)){
                array_push($dates, $row['CDate']);
                }

        if ($number > $check_number)
            $number = $check_number;

        if($dollar)
            if($result = $mysqli->query($query))
                while($row = $result->fetch_array(MYSQLI_ASSOC)){
                    array_push($values, $row[1]);
                    array_push($dollar_data, $row[1]);
                }

        if($euro)
            if($result = $mysqli->query($query))
                while($row = $result->fetch_array(MYSQLI_ASSOC)){
                    array_push($values, $row[2]);
                    array_push($euro_data, $row[2]);
                }

        if($pound)
            if($result = $mysqli->query($query))
                while($row = $result->fetch_array(MYSQLI_ASSOC)){
                    array_push($values, $row[3]);
                    array_push($pound_data, $row[3]);
                }

        $imH = 700;
        $imW = 900;
        header("Content-Type: image/png");
        $im = imageCreate($imW, $imH);  
        $bgcolor = imageColorAllocate($im, 255, 255, 200);
        $black = imageColorAllocate($im, 0, 0, 0);
        $color = imageColorAllocate($im, 184, 224, 191);
        $color_dollar = imageColorAllocate($im, 16, 133, 55);
        $color_euro = imageColorAllocate($im, 222, 252, 28);
        $color_pound = imageColorAllocate($im, 88, 10, 255);

        $y1 = $imH - 80;
        $y2 = 80;
        $x1 = 50;
        $x2 = $imW - 50;

        imagefilledrectangle($im, 0, 0, $imW, $imH, $bgcolor);
        imagefilledrectangle($im, 50, 80, $x2, $y1, $color);

        $j = 0;
        while(($i + $x1) < $x2){
            imagedashedline($im, $x1 + $i, $y1, $x1 + $i, $y2, $black);
            imagettftext($im, 11, 90, $x1 + $i + 6, $imH - 5, $black, $fontFile, $dates[$j]);
            $i += ($imW - 100) / $number;
            $j++;
        }

        $k = 0;
        $i = 0;
        while(($y1 - $i) > $y2){
            imagedashedline($im, $x1, $y1 - $i, $x2, $y1 - $i, $black);
            imagettftext($im, 11, 0, 5, $y1 - $i + 6, $black, $fontFile,  $k);
            $i += 20;
            $k += 20;
        }

        imagesetthickness($im, 4.5);
        $text = "Динамика курсов валют. Год: $year";
        imagettftext($im, 14, 0, 300, 50, $black, $fontFile, $text);

        $dollar_label = "Dollar";
        $euro_label = "Euro";
        $pound_label = "Pound";
        imagettftext($im, 12, 0, 700, 30, $black, $fontFile, $dollar_label);
        imageline($im, 760, 25, 800, 25, $color_dollar);
        imagettftext($im, 12, 0, 700, 45, $black, $fontFile, $euro_label);
        imageline($im, 760, 40, 800, 40, $color_euro);
        imagettftext($im, 12, 0, 700, 60, $black, $fontFile, $pound_label);
        imageline($im, 760, 55, 800, 55, $color_pound);



    imagepng($im);
}
?>