private bool CountWise(BordPoint p1, BordPoint p0, BordPoint p2)
{
Vector2 v1 = new Vector2(p1.p.X - p0.p.X, p1.p.Y - p0.p.Y);
Vector2 v2 = new Vector2(p2.p.X - p1.p.X, p2.p.Y - p1.p.Y);
float cross = MathTools.Vector2Cross(v1, v2);
return(cross < 0 || cross == 0 && Vector2.Dot(v1, v2) < 0);
}
public void BuildConvexHall(CircleList <BordPoint> border, float minOptimizeDest)
{
#region 获得原始凸包
if (border.Length < 2)
{
return;
}
Stack <BordPoint> stack = new Stack <BordPoint>();
CircleListNode <BordPoint> cur = border.First;
stack.Push(cur.value);
cur = cur.next;
stack.Push(cur.value);
cur = cur.next;
for (int i = 2; i < border.Length; i++)
{
BordPoint p1 = stack.Pop();
BordPoint p0 = stack.Peek();
BordPoint p2 = cur.value;
if (CountWise(p1, p0, p2))
{
stack.Push(p1);
stack.Push(p2);
cur = cur.next;
}
else
{
if (stack.Count == 1)
{
stack.Push(p2);
cur = cur.next;
}
else
{
i--;
}
}
}
List <BordPoint> templist = new List <BordPoint>(stack);
if (templist.Count > 3)
{
if (!CountWise(templist[0], templist[1], templist[templist.Count - 1]))
{
templist.RemoveAt(0);
}
if (!CountWise(templist[templist.Count - 1], templist[0], templist[templist.Count - 2]))
{
templist.RemoveAt(templist.Count - 1);
}
}
else if (templist.Count == 3)
{
if (!CountWise(templist[0], templist[1], templist[templist.Count - 1]))
{
templist.RemoveAt(0);
BordPoint temp = templist[0];
templist[0] = templist[1];
templist[1] = temp;
}
}
#endregion
#region 对凸包进行化简
if (templist.Count > 3)
{
for (int i = 0; i < templist.Count; i++)
{
Vector2 p1 = ConvertHelper.PointToVector2(templist[i].p);
Vector2 p2 = ConvertHelper.PointToVector2(templist[(i + 1) % templist.Count].p);
Vector2 p3 = ConvertHelper.PointToVector2(templist[(i + 2) % templist.Count].p);
Vector2 p4 = ConvertHelper.PointToVector2(templist[(i + 3) % templist.Count].p);
if (Vector2.Distance(p2, p3) > minOptimizeDest)
{
continue;
}
Vector2 seg1 = p2 - p1;
Vector2 seg2 = p4 - p3;
float ang = (float)Math.Acos(Vector2.Dot(seg1, seg2) / (seg1.Length() * seg2.Length()));
if (ang > MathHelper.PiOver2)
{
continue;
}
Line line1 = new Line(p1, seg1);
Line line2 = new Line(p4, seg2);
Vector2 interPoint;
if (!MathTools.InterPoint(line1, line2, out interPoint))
{
continue;
}
templist[(i + 1) % templist.Count] =
new BordPoint(templist[(i + 1) % templist.Count].index, ConvertHelper.Vector2ToPoint(interPoint));
templist.RemoveAt((i + 2) % templist.Count);
i--;
}
}
#endregion
convexPoints = templist;
}
private bool CountWise ( BordPoint p1, BordPoint p0, BordPoint p2 )
{
Vector2 v1 = new Vector2( p1.p.X - p0.p.X, p1.p.Y - p0.p.Y );
Vector2 v2 = new Vector2( p2.p.X - p1.p.X, p2.p.Y - p1.p.Y );
float cross = MathTools.Vector2Cross( v1, v2 );
return cross < 0 || cross == 0 && Vector2.Dot( v1, v2 ) < 0;
}
private void SetValueAtIndex( int index, float value, IShelterObj obj, int bordIndex, Point bordp )
{
if (index < 0 || index >= depthMap.Length)
return;
if (value < depthMap[index])
{
depthMap[index] = value;
objMap[index] = obj;
objBordIndexMap[index] = new BordPoint( bordIndex, bordp );
}
}
