检测WPF画布上两个矩形之间的碰撞

我对编程非常陌生，从C#开始。我现在正在努力制作我的第一个游戏，我决定选择蛇。到目前为止，我一直在尝试研究这个问题，但我看到的所有答案都与那些使用不同方法移动蛇的人有关。

我的程序使用两个替身（left和top）来存储蛇在Canvas上的位置。我的程序还使用了两个替身作为游戏中的"食物"，称为randomFoodSpawnLeft和randomFoodSpawnTop。

我的问题是。如何检测两个只有左值和上值的矩形对象之间的碰撞？我很困惑。

snakeWindow是窗口，snakeHead是表示蛇的矩形，left是蛇的左侧值，top是蛇的顶部值。

void timer_Tick(object sender, EventArgs e)
    {
        double left = Canvas.GetLeft(snakeHead);
        double top = Canvas.GetTop(snakeHead);
        if (keyUp)
        {
            top -= 3;
        }
        else if (keyDown)
        {
            top += 3;
        }
        else if (keyLeft)
        {
            left -= 3;
        }
        else if (keyRight)
        {
            left += 3;
        }
        // These statements see if you have hit the border of the window, default is 1024x765
        if (left < 0)
        {
            left = 0;
            gameOver = true;
        }
        if (top < 0)
        {
            top = 0;
            gameOver = true;
        }
        if (left > snakeWindow.Width)
        {
            left = 0;
            gameOver = true;
        }
        if (top > snakeWindow.Height)
        {
            top = 0;
            gameOver = true;
        }
        // Statements that detect hit collision between the snakeHead and food
        //
        if (foodEaten == true)
        {
            spawnFood();
            textBlockCurrentScore.Text += 1;
        }
            // If gameOver were to be true, then the game would have to end. In order to accomplish this I display to the user that the game is over
            // and the snakeHead is disabled, and should restart.
            if (gameOver == true)
        {
            keyRight = false;
            keyLeft = false;
            keyUp = false;
            keyDown = false;
            top = 0;
            left = 0;
            textBlockGameOver.Text = "GAME OVER!";
            snakeCanvas.Background = Brushes.Blue;
        }

        Canvas.SetLeft(snakeHead, left);
        Canvas.SetTop(snakeHead, top);
    }

Rect rect1 = new Rect(left1, top1, widht1, height1);
Rect rect2 = new Rect(left2, top2, widht2, height2);
bool intersects = rect1.IntersectsWith(rect2);