/// <summary>
/// 根据指定的方向绘制一个箭头
/// </summary>
/// <param name="g">绘图对象</param>
/// <param name="brush">笔刷</param>
/// <param name="point">起始点</param>
/// <param name="size">长度</param>
/// <param name="direction">方向</param>
public static void PaintTriangle(Graphics g, Brush brush, PointF point, int size, EGraphDirection direction)
{
PointF[] array = new PointF[4];
if (direction == EGraphDirection.Leftward)
{
array[0] = new PointF(point.X, point.Y - size);
array[1] = new PointF(point.X, point.Y + size);
array[2] = new PointF(point.X - (2 * size), point.Y);
}
else if (direction == EGraphDirection.Rightward)
{
array[0] = new PointF(point.X, point.Y - size);
array[1] = new PointF(point.X, point.Y + size);
array[2] = new PointF(point.X + (2 * size), point.Y);
}
else if (direction == EGraphDirection.Upward)
{
array[0] = new PointF(point.X - size, point.Y);
array[1] = new PointF(point.X + size, point.Y);
array[2] = new PointF(point.X, point.Y - (2 * size));
}
else
{
array[0] = new PointF(point.X - size, point.Y);
array[1] = new PointF(point.X + size, point.Y);
array[2] = new PointF(point.X, point.Y + (2 * size));
}
array[3] = array[0];
g.FillPolygon(brush, array);
}
/// <summary>
/// Paints the triangle.
/// </summary>
/// <param name="g">The g.</param>
/// <param name="brush">The brush.</param>
/// <param name="point">The point.</param>
/// <param name="size">The size.</param>
/// <param name="direction">The direction.</param>
public static void PaintTriangle(Graphics g, System.Drawing.Brush brush, Point point, int size, EGraphDirection direction)
{
Point[] array = new Point[4];
switch (direction)
{
case EGraphDirection.Leftward:
array[0] = new Point(point.X, point.Y - size);
array[1] = new Point(point.X, point.Y + size);
array[2] = new Point(point.X - 2 * size, point.Y);
break;
case EGraphDirection.Rightward:
array[0] = new Point(point.X, point.Y - size);
array[1] = new Point(point.X, point.Y + size);
array[2] = new Point(point.X + 2 * size, point.Y);
break;
case EGraphDirection.Upward:
array[0] = new Point(point.X - size, point.Y);
array[1] = new Point(point.X + size, point.Y);
array[2] = new Point(point.X, point.Y - 2 * size);
break;
default:
array[0] = new Point(point.X - size, point.Y);
array[1] = new Point(point.X + size, point.Y);
array[2] = new Point(point.X, point.Y + 2 * size);
break;
}
array[3] = array[0];
g.FillPolygon(brush, array);
}
