public void InitUV()
{
Vertex v1 = t1.Vertices[0];
Vertex v2 = t1.Vertices[1];
Vertex v3 = t1.Vertices[2];
Vertex vt1 = t2.Vertices[0];
Vertex vt2 = t2.Vertices[1];
Vertex vt3 = t2.Vertices[2];
Vector4 e1 = v2.Position - v1.Position;
Vector4 e2 = v3.Position - v2.Position;
Vector4 e3 = v1.Position - v3.Position;
Vector4 e4 = vt2.Position - vt1.Position;
Vector4 e5 = vt3.Position - vt2.Position;
Vector4 e6 = vt1.Position - vt3.Position;
float e1l = e1.Length();
float e2l = e2.Length();
float e3l = e3.Length();
float e4l = e4.Length();
float e5l = e5.Length();
float e6l = e6.Length();
float maxlength = Math.Max(Math.Max(e1l, e3l), Math.Max(e2l, e1l));
if (maxlength == e1l)
{
}
}
public bool CalculateWeight(Vector4 p)
{
Vector4 p1 = Vertices[0].ScreenSpacePosition;
Vector4 p2 = Vertices[1].ScreenSpacePosition;
Vector4 p3 = Vertices[2].ScreenSpacePosition;
float dy1 = p.Y - p1.Y;
float dy2 = p.Y - p2.Y;
float dx1 = p1.X - p.X;
float dx2 = p2.X - p.X;
Vector4 tp1 = p2 - p;
Vector4 tp2 = p3 - p;
Vector4 tp3 = p1 - p;
float d1 = tp1.Length();
float d2 = tp2.Length();
float d3 = tp3.Length();
float h1 = (l1 + d1 + d2) / 2;
float h2 = (l2 + d2 + d3) / 2;
float h3 = (l3 + d1 + d3) / 2;
float t1 = (float)Math.Sqrt(h1 * (h1 - l1) * (h1 - d1) * (h1 - d2));
float t2 = (float)Math.Sqrt(h2 * (h2 - l2) * (h2 - d2) * (h2 - d3));
float t3 = (float)Math.Sqrt(h3 * (h3 - l3) * (h3 - d3) * (h3 - d1));
//float t1 = Vector4.Cross(tp1, tp2).Length() / 2;
//float t2 = Vector4.Cross(tp3, tp2).Length() / 2;
//float t3 = Vector4.Cross(tp3, tp1).Length() / 2;
float a = t1 + t2 + t3;
;
if (a > area + 100)
{
return(false);
}
else
{
b1 = t1 / area;
//b1 = MathUtil.Clamp01(b1);
b2 = t2 / area;
//b2 = MathUtil.Clamp01(b2);
b3 = t3 / area;
//b3 = MathUtil.Clamp01(b3);
this.nowpos = p;
return(true);
}
}
public void Preproccess()
{
Vector4 p1 = this.Vertices[0].ScreenSpacePosition;
Vector4 p2 = this.Vertices[1].ScreenSpacePosition;
Vector4 p3 = this.Vertices[2].ScreenSpacePosition;
a = (int)(p2.X - p1.X);
b = (int)(p3.X - p1.X);
c = (int)(p2.Y - p1.Y);
d = (int)(p3.Y - p1.Y);
e = (int)(p2.Y - p3.Y);
f = (int)(p1.Y - p2.Y);
Vector4 e1 = p2 - p1;
Vector4 e2 = p3 - p1;
Vector4 e3 = p3 - p2;
float n1 = e1.Length();
float n2 = e2.Length();
float n3 = e3.Length();
float h = (n1 + n2 + n3) / 2;
area = (float)Math.Sqrt(h * (h - n1) * (h - n2) * (h - n3));
////公式的分母
den = d * b + e * c;
u1 = Vertices[0].UV.X / Vertices[0].ClipSpacePosition.W;
u2 = Vertices[1].UV.X / Vertices[1].ClipSpacePosition.W;
u3 = Vertices[2].UV.X / Vertices[2].ClipSpacePosition.W;
v1 = Vertices[0].UV.Y / Vertices[0].ClipSpacePosition.W;
v2 = Vertices[1].UV.Y / Vertices[1].ClipSpacePosition.W;
v3 = Vertices[2].UV.Y / Vertices[2].ClipSpacePosition.W;
//透视校正
w1 = 1.0f / Vertices[0].ClipSpacePosition.W;
w2 = 1.0f / Vertices[1].ClipSpacePosition.W;
w3 = 1.0f / Vertices[2].ClipSpacePosition.W;
}
/* 向量投影
* 给定 向量 V N ，能将V 分解成 Vh (平行于N的分向量) 和 Vv (垂直于N的分向量)
* V = Vh + Vv
* Vh 一般成为 V 在N上的投影
*/
// 在 N 上的平行分量
public Vector4 PComponent(Vector4 n)
{
return(n * (Vector4.Dot(this, n) / n.Length() * n.Length()));
}
// 两向量夹角大小
public double Degree(Vector4 A)
{
return(Math.Acos(Vector4.Dot(this, A) / this.Length() * A.Length()));
}
//
/// <summary>
/// AB的cosQ值反应了夹角的大小和方向
/// 即 取 A · B 的符号结果
/// 小于0 0' 大于等于 Q 小于 90' 方向基本相同
/// 等于0 Q<= 90' 正交
/// 大于0 90' 大于 Q 小于等于 180' 方向基本相反
///
/// </summary>
/// 矢量A
/// <param name="A"></param>
/// 矢量B
/// <param name="B"></param>
///
///
/// <returns></returns>
public float CosUV(Vector4 A)
{
return((Vector4.Dot(this, A)) / this.Length() * A.Length());
}
