兰顿的蚂蚁与PHP

Question

我用PHP为Langton的Ant编写代码。但我无法得到那个结果。

规则：

如果机器位于白色方块中，请顺时针旋转90°并向前移动1个单位；

如果机器位于黑色方块中，请逆时针旋转90°并向前移动1个单位；

每走一步，翻转基方块的颜色。

这是我的代码：

Matris.php

<?php
declare(strict_types = 1);

class Matris
{
    const white = 0;
    const black = 1;

    private $cells = array();

    public function Matris($size)
    {
        for ($x = 0; $x < $size; $x++) {
            for ($y = 0; $y < $size; $y++) {
                $this->cells[$x][$y] = Matris::white;
            }
        }
    }

    public function getCells()
    {
        echo "<table>";
        for ($x = 0; $x < count($this->cells); $x++) {
            echo "<tr>";
            for ($y = 0; $y < count($this->cells); $y++) {
                $r = $this->cells[$x][$y];
                echo "<td>$r</td>";
            }
            echo "</tr>";
        }
        echo "</table>";
    }


    public function getSize()
    {
        return count($this->cells);
    }

    public function getCellColor($x, $y)
    {
        return $this->cells[$x][$y];
    }

    public function setCellColor($x, $y, $color)
    {
        $this->cells[$x][$y] = $color;
    }


}

Ant.php

<?php

class Ant
{
    const face_right = 0;
    const face_left = 1;
    const face_top = 2;
    const face_down = 3;

    private $x, $y, $steps = 0;
    private $direction;
    private $facing;

    function __construct($x, $y, $facing)
    {
        $this->x = $x;
        $this->y = $y;
        $this->facing = $facing;
    }

    public function getSteps()
    {
        return $this->steps;
    }

    public function getDirection()
    {
        return $this->direction;
    }

    public function isInMatris($matris)
    {
        return 0 <= $this->getX() && $this->getX() < $matris->getSize() &&
        0 <= $this->getY() && $this->getY() < $matris->getSize();
    }

    public function getX()
    {
        return $this->x;
    }

    public function getY()
    {
        return $this->y;
    }

    public function step($matris)
    {
        $c = $matris->getCellColor($this->x, $this->y);
        $oldX = $this->x;
        $oldY = $this->y;
        $newColor = 0;
        if (0 === $c) {
            $this->direction = $this->turnClockwise();
            $newColor = 1;
        } else {
            $this->direction = $this->turnCounterClockwise();
            $newColor = 0;
        }

        $matris->setCellColor($oldX, $oldY, $newColor);
        $this->steps++;
    }

    private function turnClockwise()
    {
        if ($this->facing === Machine::face_right) {
            $this->x += 1;
            $this->facing = Machine::face_down;
        } else if ($this->facing === Machine::face_down) {
            $this->y -= 1;
            $this->facing = Machine::face_left;
        } else if ($this->facing === Machine::face_left) {
            $this->x -= 1;
            $this->facing = Machine::face_top;
        } else if ($this->facing === Machine::face_top) {
            $this->y += 1;
            $this->facing = Machine::face_right;
        }
        return "right";
    }

    private function turnCounterClockwise()
    {
        if ($this->facing === Machine::face_right) {
            $this->x -= 1;
            $this->facing = Machine::face_top;
        } else if ($this->facing === Machine::face_down) {
            $this->y -= 1;
            $this->facing = Machine::face_left;
        } else if ($this->facing === Machine::face_left) {
            $this->x += 1;
            $this->facing = Machine::face_down;
        } else if ($this->facing === Machine::face_top) {
            $this->y += 1;
            $this->facing = Machine::face_right;
        }
        return "left";
    }

    public function getStringResult($matris)
    {
        $fa = "";
        switch ($this->facing) {
            case $this->facing === 0:
                $fa = "right";
                break;
            case $this->facing === 1:
                $fa = "left";
                break;
            case $this->facing === 2:
                $fa = "top";
                break;
            case $this->facing === 3:
                $fa = "down";
                break;
        }
        return "(" . $this->x . "," . $this->y . "," . $this->direction . "," . $matris->getCellColor($this->x, $this->y) . "," . $fa . ")";
    }

}

Index.php

<?php
require 'Machine.php';
require 'Matris.php';


$matris = new Matris(150);
$ant = new Ant(50, 50, 0);

for ($i = 1; $i <= 100; $i++) {
    if ($ant->getSteps() < 100 && $ant->isInMatris($matris)) {
        //echo $ant->getStringResult($matris) . "<br/>";
        $ant->step($matris);
    } else {
//        echo "Finish";
    }
}
$matris->getCells();

但是在运行代码之后，我没有看到任何错误，但是结果如下图所示。

我需要使用OOP进行操作。

感谢您的任何建议。