public bool Intersect2D(SBSLine2D line, out SBSVector3 point)
{
float det = this.A * line.B - line.A * this.B;
point = SBSVector3.zero;
if (det == 0)
return false;
point.x = (line.B * this.C - this.B * line.C) / det;
point.y = (this.A * line.C - line.A * this.C) / det;
return true;
}
public static void CreateLine(Vector3[] pointList, float width, Color color, bool isClosed, out Mesh lineMesh)
{
/*
* A -------- C
* B -------- D
*/
lineMesh = new Mesh();
lineMesh.name = "lineMesh";
if (pointList.Length < 2)
return;
int vNum = pointList.Length * 2;
int tNum = (pointList.Length - 1) * 2 * 3;
int vIndex = 0;
int tIndex = 0;
Vector3[] vertices = new Vector3[vNum];
Vector2[] uv = new Vector2[vNum];
Vector3[] normals = new Vector3[vNum];
Color[] colors = new Color[vNum];
int[] triangles = new int[tNum];
if (isClosed)
triangles = new int[tNum + 2 * 3];
for (int i = 0; i < pointList.Length - 1; i++)
{
Vector3 direction = (pointList[i + 1] - pointList[i]).normalized;
Vector3 ortho = Vector3.Cross(direction, Vector3.forward);
SBSVector3 A = pointList[i] - ortho * width * 0.5f;
SBSVector3 B = pointList[i] + ortho * width * 0.5f;
direction = (pointList[i] - pointList[i + 1]).normalized;
ortho = Vector3.Cross(direction, Vector3.forward);
SBSVector3 C = pointList[i + 1] + ortho * width * 0.5f;
SBSVector3 D = pointList[i + 1] - ortho * width * 0.5f;
if (i == 0)
{
vertices[vIndex] = A;
vertices[vIndex + 1] = B;
}
else
{
SBSLine2D line1 = new SBSLine2D(vertices[vIndex - 2], vertices[vIndex]);
SBSLine2D line2 = new SBSLine2D(A, C);
SBSVector3 intersection;
bool parallel = !line1.Intersect2D(line2, out intersection);
if (parallel)
vertices[vIndex] = A;
else
vertices[vIndex] = intersection;
line1 = new SBSLine2D(vertices[vIndex - 1], vertices[vIndex + 1]);
line2 = new SBSLine2D(B, D);
parallel = !line1.Intersect2D(line2, out intersection);
if (parallel)
vertices[vIndex + 1] = B;
else
vertices[vIndex + 1] = intersection;
}
vertices[vIndex + 2] = C;
vertices[vIndex + 3] = D;
triangles[tIndex] = vIndex;
triangles[tIndex + 1] = vIndex + 2;
triangles[tIndex + 2] = vIndex + 1;
triangles[tIndex + 3] = vIndex + 1;
triangles[tIndex + 4] = vIndex + 2;
triangles[tIndex + 5] = vIndex + 3;
tIndex += 6;
vIndex += 2;
}
if (isClosed)
{
Vector3 lastPoint = pointList[pointList.Length - 1];
Vector3 firstPoint = pointList[0];
SBSVector3 A1 = vertices[0];
SBSVector3 B1 = vertices[1];
SBSVector3 C1 = vertices[2];
SBSVector3 D1 = vertices[3];
SBSVector3 A2 = vertices[vNum - 1 - 3];
SBSVector3 B2 = vertices[vNum - 1 - 2];
SBSVector3 C2 = vertices[vNum - 1 - 1];
SBSVector3 D2 = vertices[vNum - 1];
Vector3 direction = (firstPoint - lastPoint).normalized;
Vector3 ortho = Vector3.Cross(direction, Vector3.forward);
SBSVector3 A = lastPoint - ortho * width * 0.5f;
SBSVector3 B = lastPoint + ortho * width * 0.5f;
direction = (lastPoint - firstPoint).normalized;
ortho = Vector3.Cross(direction, Vector3.forward);
SBSVector3 C = firstPoint + ortho * width * 0.5f;
SBSVector3 D = firstPoint - ortho * width * 0.5f;
SBSLine2D line1 = new SBSLine2D(A2, C2);
SBSLine2D line2 = new SBSLine2D(A, C);
SBSVector3 intersection;
bool parallel = !line1.Intersect2D(line2, out intersection);
if (parallel)
vertices[vIndex] = A;
else
vertices[vIndex] = intersection;
line1 = new SBSLine2D(B2, D2);
line2 = new SBSLine2D(B, D);
parallel = !line1.Intersect2D(line2, out intersection);
if (parallel)
vertices[vIndex + 1] = B;
else
vertices[vIndex + 1] = intersection;
line1 = new SBSLine2D(A, C);
line2 = new SBSLine2D(A1, C1);
parallel = !line1.Intersect2D(line2, out intersection);
if (parallel)
vertices[0] = A1;
else
vertices[0] = intersection;
line1 = new SBSLine2D(B, D);
line2 = new SBSLine2D(B1, D1);
parallel = !line1.Intersect2D(line2, out intersection);
if (parallel)
vertices[1] = B1;
else
vertices[1] = intersection;
triangles[tIndex] = vIndex;
triangles[tIndex + 1] = 0;
triangles[tIndex + 2] = vIndex + 1;
triangles[tIndex + 3] = vIndex + 1;
triangles[tIndex + 4] = 0;
triangles[tIndex + 5] = 1;
}
for (int i = 0; i < vNum; i++)
{
uv[i] = Vector2.zero;
normals[i] = -Vector3.forward;
colors[i] = color;
}
lineMesh.vertices = vertices;
lineMesh.uv = uv;
lineMesh.normals = normals;
lineMesh.colors = colors;
string log = string.Empty;
for (int i = 0; i < triangles.Length; i++)
log += triangles[i] + ", ";
//Debug.Log(" triangles: " + log);
lineMesh.triangles = triangles;
}