Finally got back from the generic LABELS, fixed that.

[Nicholas Randall Forystek]

Public Declare Function VertexPoint_Behind_TrianglePlane Lib
"maxlandlib.dll" Alias "PointBehindPoly" _
(ByVal VertexPointX As Single, ByVal VertexPointY As
Single, ByVal VertexPointZ As Single, _
ByVal TrianglePlaneNormalX As Single, ByVal
TrianglePlaneNormalY As Single, ByVal TrianglePlaneNormalZ As Single, _
ByVal TriangleSideLength1 As Single, ByVal
TriangleSideLength2 As Single, ByVal TriangleSideLength3 As Single) As
Boolean

Public Sub Main()

Dim v As D3DVECTOR
Dim n As D3DVECTOR
Dim p As D3DVECTOR
Dim t1 As D3DVECTOR
Dim t2 As D3DVECTOR
Dim t3 As D3DVECTOR

'make three points of a triangle
t1.x = 20: t2.y = 0: t3.z = 0
t1.x = 20: t2.y = 20: t3.z = 0
t1.x = -20: t2.y = -20: t3.z = 0

'get plane normal of a triangle
n = GetPlaneNormal(t1, t2, t3)

'get lengths of triangle sides
v.x = Distance(t3, t1)
v.y = Distance(t1, t2)
v.z = Distance(t2, t3)

'make up a point test scenario
p.x = 0: p.y = 0: p.z = 30

'check to see if the point is behind the illogical spun traingular
sphere in back spuns
Debug.Print VertexPoint_Behind_TrianglePlane(p.x, p.y, p.z, n.x, n.y,
n.z, v.x, v.y, v.z)

End Sub

Public Function Distance(ByRef p1 As D3DVECTOR, ByRef p2 As D3DVECTOR) As
Single
Distance = Sqr(((p1.x - p2.x) * (p1.x - p2.x)) + ((p1.y - p2.y) *
(p1.y - p2.y)) + ((p1.z - p2.z) * (p1.z - p2.z)))
End Function

Public Function GetPlaneNormal(ByRef v0 As D3DVECTOR, ByRef v1 As D3DVECTOR,
ByRef v2 As D3DVECTOR) As D3DVECTOR

Dim vector1 As D3DVECTOR
Dim vector2 As D3DVECTOR
Dim vector3 As D3DVECTOR

'/*Calculate the Normal*/
'/*Vector 1*/
vector1 = VectorSubtract(v0, v1)

'/*Vector 2*/
vector2 = VectorSubtract(v1, v2)

'/*Apply the Cross Product*/
vector3 = VectorCrossProduct(vector1, vector2)

'/*Normalize the Vector*/
GetPlaneNormal = VectorNormalize(vector3)

End Function

Public Function VectorCrossProduct(ByRef v As D3DVECTOR, ByRef u As
D3DVECTOR) As D3DVECTOR
VectorCrossProduct.x = v.y * u.z - v.z * u.y
VectorCrossProduct.y = v.z * u.x - v.x * u.z
VectorCrossProduct.z = v.x * u.y - v.y * u.x
End Function

Public Function VectorSubtract(ByRef v As D3DVECTOR, ByRef u As D3DVECTOR)
As D3DVECTOR
VectorSubtract.x = v.x - u.x
VectorSubtract.y = v.y - u.y
VectorSubtract.z = v.z - u.z
End Function

Public Function VectorNormalize(ByRef v As D3DVECTOR) As D3DVECTOR
Dim l As Single
l = Sqr(v.x * v.x + v.y * v.y + v.z * v.z)
If l = 0 Then l = 1
VectorNormalize.x = (v.x / l)
VectorNormalize.y = (v.y / l)
VectorNormalize.z = (v.z / l)
End Function