C#. Рисование кружочков с использованием SmallBasicLibrary

Circles.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.SmallBasic.Library;

class Program
{
    private static Primitive circle2;
    static double vx2 = 0;
    static double vy2 = 0;
    static void Main(string[] args)
    {
        GraphicsWindow.Show();

        GraphicsWindow.PenColor = "blue";
        GraphicsWindow.BrushColor = "cyan";
        int circle_width = 50, circle_height = 50;
        
        int width = 640;GraphicsWindow.Width=width;
        int height = 400;GraphicsWindow.Height=height;
        Primitive circle= Shapes.AddEllipse(circle_width, circle_height);
        Shapes.Move(circle, width/2-circle_width/2 , height/2-circle_height/2);
        double vx = 5;
        double vy = 3;

         circle2 = Shapes.AddEllipse(circle_width, circle_height);
        Shapes.Move(circle2, width / 2 - circle_width / 2, height / 2 - circle_height / 2);
        

        GraphicsWindow.KeyDown += GraphicsWindow_KeyDown;

        while (true)
        {
            UpdateCircle(circle, ref vx, ref vy,circle_width, circle_height);
            //UpdateCircle(circle2, ref vx2, ref vy2, circle_width, circle_height);
            Microsoft.SmallBasic.Library.Program.Delay(30);
        }

        //Primitive circle2 = Shapes.AddEllipse(circle_width, circle_height);
        //int duration = 1000;
        //double destX = width - circle_width ;
        //double destY = height - circle_height ;
        
        //Animate(circle2,destX, destY,duration);

        //Shapes.Animate(circle2, 0, 0, 1000);
    }

    private static void GraphicsWindow_KeyDown()
    {
        if(GraphicsWindow.LastKey=="Left")
        {
            vx2 = -10;
            UpdateCircle(circle2,ref vx2,ref vy2,50,50);
        }
        else if(GraphicsWindow.LastKey=="Right")
        {
            double vx2 = 10;
            UpdateCircle(circle2, ref vx2, ref vy2, 50, 50);
        }
    }

    private static void UpdateCircle(Primitive circle, ref double vx, ref double vy,int circle_width, int circle_height)
    {
        double x = Shapes.GetLeft(circle) + vx;
        if (x + circle_width > GraphicsWindow.Width)
        {
            x = GraphicsWindow.Width - circle_width;
            vx *= -1;
        }
        else if (x < 0)
        {
            x = 0;
            vx *= -1;
        }

        double y = Shapes.GetTop(circle) + vy;
        if (y + circle_height > GraphicsWindow.Height)
        {
            y = GraphicsWindow.Height - circle_height;
            vy *= -1;
        }
        else if (y < 0)
        {
            y = 0;
            vy *= -1;
        }
        Shapes.Move(circle, x, y);
    }

    private static void Animate(Primitive circle2,double destX, double destY, int duration)
    {
        int steps = 100;
        double stepX = (destX- Shapes.GetLeft(circle2))/steps;
        double stepY = (destY- Shapes.GetTop(circle2))/steps;

        for (int i = 0; i < steps; i++)
        {
            double left = Shapes.GetLeft(circle2);
            double top = Shapes.GetTop(circle2);
            Shapes.Move(circle2, left + stepX, top + stepY);

            Microsoft.SmallBasic.Library.Program.Delay(duration/steps);
        }
    }
}