This helped btw, I think I made the width too big somehow (looking back at the code, I didn't divide by 2; fixed it here) because I overshot it and reopened the game 15 times, and when I tried to fix it, it double clicked a pixel and deleted everything. This took like two hours to run as well, so I don't really feel like trying again.

import java.awt.Robot; 
import java.awt.event.InputEvent;  
public class Main 
{
    public static void main(String[] args)
    {
        try
        {
            Robot rob = new Robot();
            int startX = 780;
            int startY = 271;
            int width = 362;
            int height = 540;
            int secondsBeforeStarting = 3;
            rob.delay(secondsBeforeStarting * 1000);
            for(var i=0; i<width/2; i++)
            {
                for(var j=0; j<height/2; j++)
                {
                    rob.mouseMove(startX+i*2, startY+j*2);
                    rob.mousePress(InputEvent.BUTTON1_MASK);
                    rob.delay(50);
                    rob.mouseRelease(InputEvent.BUTTON1_MASK);
                    rob.delay(50);
                }
            }
        }
        catch(Exception e)
        {
        }
    }
}