private void Cav_MouseDown(object sender, MouseButtonEventArgs e)
{
if (e.MouseDevice.LeftButton == MouseButtonState.Pressed)
{
GrainBase gb = new GrainBase();
var ui = e.GetPosition(Cav);
gb.x = ui.X;
gb.y = ui.Y;
gb.xa = rand.NextDouble() * 2 - 1;
gb.ya = rand.NextDouble() * 2 - 1;
gb.max = 8000;
grains.Add(gb);
}
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
mousePoint.max = 20000;
grains.Add(mousePoint);
//// 添加粒子
//// x，y为粒子坐标，xa, ya为粒子xy轴加速度，max为连线的最大距离
for (int i = 0; i < 100; i++)
{
GrainBase gb = new GrainBase();
gb.x = rand.NextDouble() * Cav.ActualWidth;
gb.y = rand.NextDouble() * Cav.ActualHeight;
gb.xa = rand.NextDouble() * 2 - 1;
gb.ya = rand.NextDouble() * 2 - 1;
gb.max = 8000;
grains.Add(gb);
}
//grainsEqual.Add(mousePoint);
//grains.ForEach(i => grainsEqual.Add(i));
}
public void AyKeyFrame()
{
Cav.Children.Clear();
for (int i = 0; i < grains.Count; i++)
{
GrainBase dot = grains[i];
if (dot.x == null || dot.y == null)
{
continue;
}
#region 创建碰撞粒子
// 粒子位移
dot.x += dot.xa;
dot.y += dot.ya;
// 遇到边界将加速度反向
dot.xa *= (dot.x.Value > Cav.ActualWidth || dot.x.Value < 0) ? -1 : 1;
dot.ya *= (dot.y.Value > Cav.ActualHeight || dot.y.Value < 0) ? -1 : 1;
// 绘制点
Ellipse elip = new Ellipse();
elip.Width = 2;
elip.Height = 2;
Canvas.SetLeft(elip, dot.x.Value - 0.5);
Canvas.SetTop(elip, dot.y.Value - 0.5);
elip.Fill = new SolidColorBrush(Colors.White);
Cav.Children.Add(elip);
#endregion
//判断是不是最后一个，就不用两两比较了
int endIndex = i + 1;
if (endIndex == grains.Count)
{
continue;
}
for (int j = endIndex; j < grains.Count; j++)
{
GrainBase d2 = grains[j];
double xc = dot.x.Value - d2.x.Value;
double yc = dot.y.Value - d2.y.Value;
// 两个粒子之间的距离
double dis = xc * xc + yc * yc;
// 距离比
double ratio;
// 如果两个粒子之间的距离小于粒子对象的max值，则在两个粒子间画线
if (dis < d2.max)
{
// 计算距离比
ratio = (d2.max - dis) / d2.max;
Line line = new Line();
double opacity = ratio + 0.2;
if (opacity > 1)
{
opacity = 1;
}
byte ar = (byte)(opacity * 255);
line.Stroke = new SolidColorBrush(Color.FromArgb(ar, 255, 255, 255));
line.StrokeThickness = ratio / 2;
line.X1 = dot.x.Value;
line.Y1 = dot.y.Value;
line.X2 = d2.x.Value;
line.Y2 = d2.y.Value;
Cav.Children.Add(line);
}
}
}
}
