public static bool Contains2DPoint(Vector2 point, Vector2 p0, Vector2 p1, Vector2 p2, TriangleEpsilon epsilon = new TriangleEpsilon())
{
return(Contains3DPoint(point, false, p0, p1, p2, epsilon));
}
public static bool Contains3DPoint(Vector3 point, bool checkOnPlane, Vector3 p0, Vector3 p1, Vector3 p2, TriangleEpsilon epsilon = new TriangleEpsilon())
{
Vector3 edge0 = p1 - p0;
Vector3 edge1 = p2 - p1;
Vector3 edge2 = p0 - p2;
Vector3 normal = Vector3.Cross(edge0, -edge2).normalized;
if (checkOnPlane)
{
float distanceToPt = Vector3.Dot(point - p0, normal);
if (Mathf.Abs(distanceToPt) > epsilon.ExtrudeEps)
{
return(false);
}
}
Vector3 edgeNormal = Vector3.Cross(edge0, normal).normalized;
if (Vector3.Dot(point - p0, edgeNormal) > epsilon.AreaEps)
{
return(false);
}
edgeNormal = Vector3.Cross(edge1, normal).normalized;
if (Vector3.Dot(point - p1, edgeNormal) > epsilon.AreaEps)
{
return(false);
}
edgeNormal = Vector3.Cross(edge2, normal).normalized;
if (Vector3.Dot(point - p2, edgeNormal) > epsilon.AreaEps)
{
return(false);
}
return(true);
}
public static bool Raycast(Ray ray, out float t, Vector3 p0, Vector3 p1, Vector3 p2, TriangleEpsilon epsilon = new TriangleEpsilon())
{
t = 0.0f;
float rayEnter;
Plane trianglePlane = new Plane(p0, p1, p2);
if (trianglePlane.Raycast(ray, out rayEnter) &&
Contains3DPoint(ray.GetPoint(rayEnter), false, p0, p1, p2, epsilon))
{
t = rayEnter;
return(true);
}
if (epsilon.ExtrudeEps != 0.0f)
{
float dot = Vector3Ex.AbsDot(ray.direction, trianglePlane.normal);
if (dot < ExtrudeEpsThreshold.Get)
{
OBB obb = Calc3DTriangleOBB(p0, p1, p2, trianglePlane.normal, epsilon);
return(BoxMath.Raycast(ray, obb.Center, obb.Size, obb.Rotation));
}
}
return(false);
}
public static bool RaycastWire(Ray ray, out float t, Vector3 p0, Vector3 p1, Vector3 p2, TriangleEpsilon epsilon = new TriangleEpsilon())
{
t = 0.0f;
float rayEnter;
Plane trianglePlane = new Plane(p0, p1, p2);
if (trianglePlane.Raycast(ray, out rayEnter))
{
Vector3 intersectPt = ray.GetPoint(rayEnter);
float distToSegment = intersectPt.GetDistanceToSegment(p0, p1);
if (distToSegment <= epsilon.WireEps)
{
t = rayEnter;
return(true);
}
distToSegment = intersectPt.GetDistanceToSegment(p1, p2);
if (distToSegment <= epsilon.WireEps)
{
t = rayEnter;
return(true);
}
distToSegment = intersectPt.GetDistanceToSegment(p2, p0);
if (distToSegment <= epsilon.WireEps)
{
t = rayEnter;
return(true);
}
}
if (epsilon.ExtrudeEps != 0.0f)
{
float dot = Vector3Ex.AbsDot(ray.direction, trianglePlane.normal);
if (dot < ExtrudeEpsThreshold.Get)
{
OBB obb = Calc3DTriangleOBB(p0, p1, p2, trianglePlane.normal, epsilon);
return(BoxMath.Raycast(ray, obb.Center, obb.Size, obb.Rotation));
}
}
return(false);
}
public static OBB Calc3DTriangleOBB(Vector3 p0, Vector3 p1, Vector3 p2, Vector3 normal, TriangleEpsilon epsilon = new TriangleEpsilon())
{
const float eps = 1e-5f;
Vector3 lgEdgeStart = p0;
Vector3 lgEdgeEnd = p1;
Vector3 oppositePt = p2;
float sqrEdgeLength = (p0 - p1).sqrMagnitude + eps; // Add small epsilon to avoid problems with equilateral triangles
float nextSqrLength = (p1 - p2).sqrMagnitude;
if (nextSqrLength > sqrEdgeLength)
{
lgEdgeStart = p1;
lgEdgeEnd = p2;
oppositePt = p0;
sqrEdgeLength = nextSqrLength;
}
nextSqrLength = (p2 - p0).sqrMagnitude;
if (nextSqrLength > sqrEdgeLength)
{
lgEdgeStart = p2;
lgEdgeEnd = p0;
oppositePt = p1;
sqrEdgeLength = nextSqrLength;
}
Quaternion obbRotation = Quaternion.LookRotation((lgEdgeEnd - lgEdgeStart).normalized, normal);
OBB obb = new OBB(obbRotation);
float sizeAdd = 2.0f * epsilon.AreaEps;
float obbDepth = Mathf.Sqrt(sqrEdgeLength) + sizeAdd;
float dotRight = Vector3.Dot(obb.Right, (oppositePt - lgEdgeStart));
float obbWidth = Mathf.Abs(dotRight) + sizeAdd;
float obbHeight = epsilon.ExtrudeEps * 2.0f;
obb.Size = new Vector3(obbWidth, obbHeight, obbDepth);
Vector3 right = obb.Right * Mathf.Sign(dotRight);
obb.Center = right * obbWidth * 0.5f - right * epsilon.AreaEps +
lgEdgeStart - obb.Look * epsilon.AreaEps + obb.Look * obbDepth * 0.5f;
return(obb);
}
