我想创建这个函数：

void drawSquare(int x) {
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.forward(x);
    tortuga.right(90);
}

但是，我发现标识符“tortuga”未定义。
我试着这样修改函数：

void drawSquare(int x) {
    ct::TurtleScreen scr;
    scr.bgcolor({ "white" });
    ct::Turtle tortuga(scr);
    Home(tortuga);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.pencolor({ "red" });
    tortuga.speed(ct::TS_FASTEST);
    scr.exitonclick();
}

我知道标识符“tortuga”现在已经定义好了，这看起来很有效。但是，出现了20多个窗口，在每个窗口中，乌龟只画了一个正方形的三条边，如下图所示：image我希望绘制螺旋。
以下是所有的程序：

#include"CTurtle.hpp"
#include <iostream>
using namespace std;
#define Home(x) x.left(90)

namespace ct = cturtle;
int shellSize;
int initialShellSize;


void drawSquare(int x) {
    ct::TurtleScreen scr;
    scr.bgcolor({ "white" });
    ct::Turtle tortuga(scr);
    Home(tortuga);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.forward(x);
    tortuga.right(90);
    tortuga.pencolor({ "red" });
    tortuga.speed(ct::TS_FASTEST);
    scr.exitonclick();
}

int main(int argc, char** argv) {
    std::cout << "Type the size of the outershell of the spiral: "; // Type a number and press enter
    std::cin >> shellSize; // Get user input from the keyboard
    initialShellSize = shellSize;
    
    for (int i = 10; i <= initialShellSize; i = i + 10)
    {
        shellSize = initialShellSize - (initialShellSize/i);
        drawSquare(shellSize);
    }
    
    return 0;
}