/// 如果端点在前，返回true，否则是false
/// <param name="ray"></param>
/// <param name="p1">端点</param>
/// <param name="p2">交点</param>
private static void HitLineSeg(Ray ray, uint line, out Point p1, out Point p2, out bool b1, out bool b2)
{
LineSeg lineSeg = new LineSeg(ray.Origin, ray.NormalDirection * (float.MaxValue / 10000) + ray.Origin,
LineSegs[line].Normal, 0);
float p1l = ray.Direction.Magnitude();
float p2l = float.MaxValue;
p1 = new Point(LineSegs[line].Material, line, ray.Direction + ray.Origin);
p2 = new Point();
b1 = true;
b2 = false;
for (uint i = 0; i < LineSegs.Length; i++)
{
if (line == i)
{
continue;
}
if (!LineSeg.IsIntersect(lineSeg, LineSegs[i], out Vector2 vector2))
{
continue;
}
if (vector2 == p1.Position)
{
continue;
}
if (vector2 == LineSegs[i].P1 || vector2 == LineSegs[i].P2)
{
continue;
}
float l = (ray.Origin - vector2).Magnitude();
if (l < p1l && b1)
{
b1 = false;
}
if (l < p2l)
{
p2l = l;
if (l < p1l || LineSegs[i].Normal * (ray.Origin - LineSegs[i].Position) < 0)
{
b2 = false;
continue;
}
p2 = new Point(LineSegs[i].Material, i, vector2);
b2 = true;
}
}
if (b2 && (p2.Position == LineSegs[p2.Line].P1 || p2.Position == LineSegs[p2.Line].P2))
{
b2 = false;
}
}
private static void Sampling(int x, int y, bool debug = false)
{
Vector2 Origin = new Vector2(x, y);
Color32 color = new Color32();
if (World.IsInside(Origin, out Point p))
{
color = Materials[p.Materail].GetColor();
Buff[y * Width * 4 + x * 4] = color.B;
Buff[y * Width * 4 + x * 4 + 1] = color.G;
Buff[y * Width * 4 + x * 4 + 2] = color.R;
Buff[y * Width * 4 + x * 4 + 3] = 1;
return;
}
List <Point>[] points = new List <Point> [LineSegs.Length];
for (int i = 0; i < points.Length; i++)
{
points[i] = new List <Point>();
}
foreach (LineSeg lineSeg in LineSegs)
{
float l = lineSeg.Normal * (Origin - lineSeg.Position);
if (l < 0)
{
continue;
}
bool isOnline = l == 0;
HitLineSeg(new Ray(Origin, lineSeg.P1 - Origin), lineSeg.ID, out Point p1,
out Point p2, out bool b1, out bool b2);
if (!isOnline)
{
HitLineSeg(new Ray(Origin, lineSeg.P2 - Origin), lineSeg.ID, out Point p3,
out Point p4, out bool b3, out bool b4);
if (b3)
{
points[p3.Line].Add(p3);
}
if (b4)
{
points[p4.Line].Add(p4);
}
}
if (b1)
{
points[p1.Line].Add(p1);
}
if (b2)
{
points[p2.Line].Add(p2);
}
}
foreach (List <Point> point in points)
{
if (point.Count < 2)
{
continue;
}
if (point.Count == 2)
{
if (point[0].Position == point[1].Position)
{
continue;
}
color += Math.Abs(Vector2.Angle(point[0].Position - Origin, point[1].Position - Origin)) /
Mathf.TwoPi * Materials[point[0].Materail].GetColor();
continue;
}
Point lastPoint = point[0];
for (int i = 0; i < point.Count; i++)
{
Point p1 = point[i];
if (p1.Position == lastPoint.Position && i != 0)
{
point.RemoveAt(i--);
continue;
}
lastPoint = p1;
p1.Distance = (LineSegs[p1.Line].P1 - p1.Position).Magnitude();
point[i] = p1;
}
if (point.Count % 2 == 1)
{
continue;
}
point.Sort();
for (int i = 0; i < point.Count; i += 2)
{
color += Math.Abs(Vector2.Angle(point[i].Position - Origin, point[i + 1].Position - Origin)) /
Mathf.TwoPi * Materials[point[i].Materail].GetColor();
}
}
Buff[y * Width * 4 + x * 4] = color.B;
Buff[y * Width * 4 + x * 4 + 1] = color.G;
Buff[y * Width * 4 + x * 4 + 2] = color.R;
Buff[y * Width * 4 + x * 4 + 3] = 1;
#region debug
//if (debug)
//{
// foreach (List<Point> point in points)
// {
// if (point.Count % 2 == 1 && point.Count != 1)
// {
// Console.WriteLine(new Vector2(x, y));
// //foreach (Point point1 in point)
// //{
// // DrawLine(LineSegs[point1.Line].P1, LineSegs[point1.Line].P2, new Color32(0, 0, 1));
// //}
// //foreach (Point point1 in point)
// //{
// // DrawLine(Origin, point1.Position, new Color32(0, 0, 1));
// //}
// continue;
// }
// foreach (Point point1 in point)
// {
// DrawLine(Origin, point1.Position, new Color32(0, 1, 0));
// }
// }
//}
#endregion
}