日期:2014-05-18 浏览次数:20786 次
private void timer_Tick(object sender, EventArgs e) { Tick++; if (Tick % 10 == 0) { SnowFlake s = new SnowFlake(); Random rd = new Random(); s.X = rand.Next(-20, this.Width + 20); s.Y = 0f; s.XVelocity = (float)(rand.NextDouble() - 0.5f) * 2f; s.YVelocity = (float)(rand.NextDouble() * 3) + 1f; s.Rotation = rand.Next(0, 359); s.RotVelocity = rand.Next(-3, 3) * 2; s.image = Image.FromFile(@"Resources\" + rd.Next(1, 4) + ".gif"); if (s.RotVelocity == 0) { s.RotVelocity = 3; } s.Scale = (float)(rand.NextDouble() / 2) + 0.75f; SnowFlakes.Add(s); } Graphics g = Graphics.FromImage(screenImage); g.Clear(Color.Transparent); g.SmoothingMode = SmoothingMode.HighSpeed; for (int i = 0; i < SnowFlakes.Count; i++) { SnowFlake s1 = SnowFlakes[i]; s1.X += s1.XVelocity; s1.Y += s1.YVelocity; s1.Rotation += s1.RotVelocity; s1.XVelocity += ((float)rand.NextDouble() - 0.5f) * 0.7f; s1.XVelocity = Math.Max(s1.XVelocity, -2f); s1.XVelocity = Math.Min(s1.XVelocity, +2f); if (s1.Y > this.Height) { SnowFlakes.RemoveAt(i); } else { g.ResetTransform(); g.TranslateTransform(-16, -16, MatrixOrder.Append); //pan g.ScaleTransform(s1.Scale, s1.Scale, MatrixOrder.Append); //scale g.RotateTransform(s1.Rotation, MatrixOrder.Append); //rotate g.TranslateTransform(s1.X, s1.Y, MatrixOrder.Append); //pan g.DrawImage(s1.image, 0, 0); //draw } } g.Dispose(); SetBackground(screenImage); }