file/routes/web.php

<?php

use App\Image\Processor;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Route;
use Jcupitt\Vips\Image;

/*
|--------------------------------------------------------------------------
| Web Routes
|--------------------------------------------------------------------------
|
| Here is where you can register web routes for your application. These
| routes are loaded by the RouteServiceProvider within a group which
| contains the "web" middleware group. Now create something great!
|
*/

Route::get('/', function (Request $request) {

    // && !isset($request->h)
    if (isset($request->w) && isset($request->h)) {
        $image = Image::thumbnail('../public/image.jpg', $request->w, ['height' => $request->h, 'crop' => 'centre']);
    }

    if (isset($request->w) && !isset($request->h)) {
        $image = Image::thumbnail('../public/image.jpg', $request->w, ['height' => getimagesize('../public/image.jpg')[1]]);
    }

    if (!isset($request->w) && isset($request->h)) {
        $image = Image::thumbnail('../public/image.jpg', getimagesize('../public/image.jpg')[0], ['height' => $request->h]);
    }

    $y = null;
    $x = null;

    if (isset($request->brightness) || isset($request->saturation)) {
        $image = Processor::brightness($image, isset($request->brightness) ? $request->brightness : 1.0, isset($request->saturation) ? $request->saturation : 1.0);
    }

    if ($request->rotation) {
        $image = $image->rotate($request->rotation);
    }


    // ----------------------------------------------------------------------------------------
    if ($request->cpx) {
        $GLOBALS['x'] = $request->cpx;
    } else {
        $GLOBALS['x'] = ($image->width - $request->w) / 2;
    }

    if ($request->cpy) {
        $GLOBALS['y'] = $request->cpy;
    } else {
        $GLOBALS['y'] = ($image->height - $request->h) / 2;
    }


    if ($request->debug == true) {

        if (!$request->cpx) {
            $image = $image->draw_line(1000, $image->width / 2, 0, $image->width / 2, $image->height);
        }

        if (!$request->cpy) {
            $image = $image->draw_line(1000, 0, $image->height / 2, $image->width, $image->height / 2);
        }

        if ($request->cpx) {
            $image = $image->draw_line(1000, $request->cpx, 0, $request->cpx, $image->height);
        }

        if ($request->cpy) {
            $image = $image->draw_line(1000, 0, $request->cpy, $image->width, $request->cpy);
        }
    }
    // ----------------------------------------------------------------------------------------

    if ($request->flip == "h") {
        $image = $image->fliphor();
    }

    if ($request->flip == "v") {
        $image = $image->flipver();
    }



    $image->writeToFile('image-modified.jpg', [
        'Q' => $request->q
    ]);

    return response()->file(public_path("image-modified.jpg"));
});