public static Vector2 InterpolateUV(this VertexTriangle triangle, Vector3 screenPosition)
{
float w1, w2, w3;
triangle.InterpolateWeight(screenPosition, out w1, out w2, out w3);
return(w1 * triangle.Vertexs[0].UV + w2 * triangle.Vertexs[1].UV + w3 * triangle.Vertexs[2].UV);
}
public static void GetInCubeVertexs(this VertexTriangle triangle, List <Vertex> outVertex)
{
foreach (var vertex in triangle.Vertexs)
{
if (MathTool.IsInCube(vertex.WorldPosition, 1, -1, 1, -1, 1, -1) == false)
{
outVertex.Add(vertex);
}
}
}
public static bool IsContain(this VertexTriangle triangle, Vector3 screenPosition)
{
double d1 = MathTool.Sign(screenPosition - triangle.Vertexs[1].WorldPosition, triangle.Vertexs[0].WorldPosition - triangle.Vertexs[1].WorldPosition);
double d2 = MathTool.Sign(screenPosition - triangle.Vertexs[2].WorldPosition, triangle.Vertexs[1].WorldPosition - triangle.Vertexs[2].WorldPosition);
double d3 = MathTool.Sign(screenPosition - triangle.Vertexs[0].WorldPosition, triangle.Vertexs[2].WorldPosition - triangle.Vertexs[0].WorldPosition);
bool hasNeg = (d1 < 0) || (d2 < 0) || (d3 < 0);
bool hasPos = (d1 > 0) || (d2 > 0) || (d3 > 0);
return(!(hasNeg && hasPos));
}
public static void InterpolateWeight(this VertexTriangle triangle, Vector3 screenPosition, out float w1, out float w2, out float w3)
{
Vector3 v3Tov2 = triangle.Vertexs[1].WorldPosition - triangle.Vertexs[2].WorldPosition;
Vector3 v2Tov1 = triangle.Vertexs[0].WorldPosition - triangle.Vertexs[1].WorldPosition;
Vector3 v1Tov3 = triangle.Vertexs[2].WorldPosition - triangle.Vertexs[0].WorldPosition;
Vector3 v3ToP = screenPosition - triangle.Vertexs[2].WorldPosition;
w1 = (v3Tov2.Y * v3ToP.X + -v3Tov2.X * v3ToP.Y) / (v3Tov2.Y * -v1Tov3.X + -v3Tov2.X * -v1Tov3.Y);
w2 = (v1Tov3.Y * v3ToP.X + -v1Tov3.X * v3ToP.Y) / (v3Tov2.Y * -v1Tov3.X + -v3Tov2.X * -v1Tov3.Y);
w3 = 1 - w1 - w2;
}
public static VertexTriangle Clone(this VertexTriangle triangle)
{
VertexTriangle clone = new VertexTriangle();
for (int i = 0; i < triangle.Vertexs.Length; i++)
{
var v = triangle.Vertexs[i].Clone();
v.Owner = clone;
clone.Vertexs[i] = v;
}
return(clone);
}
public static Color InterpolateColor(this VertexTriangle triangle, Vector3 screenPosition)
{
float w1, w2, w3;
triangle.InterpolateWeight(screenPosition, out w1, out w2, out w3);
float colorR = w1 * triangle.Vertexs[0].Color.R + w2 * triangle.Vertexs[1].Color.R + w3 * triangle.Vertexs[2].Color.R;
float colorG = w1 * triangle.Vertexs[0].Color.G + w2 * triangle.Vertexs[1].Color.G + w3 * triangle.Vertexs[2].Color.G;
float colorB = w1 * triangle.Vertexs[0].Color.B + w2 * triangle.Vertexs[1].Color.B + w3 * triangle.Vertexs[2].Color.B;
return(Color.FromArgb((int)colorR, (int)colorG, (int)colorB));
}
public static void SetVertexs(this VertexTriangle triangle, List <Vertex> list)
{
if (list.Count != 3)
{
return;
}
for (int i = 0; i < 3; i++)
{
list[i].Owner = triangle;
triangle.Vertexs[i] = list[i];
}
}
public static void GetMinRect(this VertexTriangle triangle, out int minX, out int maxX, out int minY, out int maxY)
{
minX = int.MaxValue;
maxX = int.MinValue;
minY = int.MaxValue;
maxY = int.MinValue;
foreach (var v in triangle.Vertexs)
{
MathTool.CompareMinMax(v.WorldPosition.X, ref minX, ref maxX);
MathTool.CompareMinMax(v.WorldPosition.Y, ref minY, ref maxY);
}
}
public Triangle()
{
List <Vertex> vertex = new List <Vertex>();
vertex.Add(new Vertex()
{
WorldPosition = new Vector3(0, 0, 100), Color = Color.Green
});
vertex.Add(new Vertex()
{
WorldPosition = new Vector3(_scale.X, 0, 100), Color = Color.Red
});
vertex.Add(new Vertex()
{
WorldPosition = new Vector3(_scale.X / 2, _unitHeight * _scale.Y, 100), Color = Color.Blue
});
Triangles = new VertexTriangle[1];
Triangles[0] = new VertexTriangle();
Triangles[0].SetVertexs(vertex);
}
