Util.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace MundoMusical.EFFECTS
{
    public static class Util
    {
        public enum Effect { Roll, Slide, Center, Blend }

        public static void Animate(Control ctl, Effect effect, int msec, int angle)
        {
            int flags = effmap[(int)effect];
            if (ctl.Visible) { flags |= 0x10000; angle += 180; }
            else
            {
                if (ctl.TopLevelControl == ctl) flags |= 0x20000;
                else if (effect == Effect.Blend) throw new ArgumentException();
            }
            flags |= dirmap[(angle % 360) / 45];
            bool ok = AnimateWindow(ctl.Handle, msec, flags);
            if (!ok) throw new Exception("Animation failed.");
            ctl.Visible = !ctl.Visible;
        }

        private static int[] dirmap = { 1, 5, 4, 6, 2, 10, 8, 9 };
        private static int[] effmap = { 0, 0x40000, 0x10, 0x80000 };

        [DllImport("user32.dll")]
        private static extern bool AnimateWindow(IntPtr handle, int msec, int flags);
    }
}