Array question

[hog]

I know the content of this is DirectX but the problem I have is the mechanics of the usage of the array hence posting here:)

 

 

I don't follow how this code works and hope someone can explain.

 

Here goes;

 

Public Function CreateTextures() As Boolean

       Dim Verts As CustomVertex()
       Dim intX As Integer

       Dim strTexturePath As String

       Try

           For intX = 1 To 10

               strTexturePath = Application.StartupPath & "\walk" & CStr(intX) & ".bmp"

               Textures(intX - 1) = TextureLoader.FromFile(m_objDevice, strTexturePath)

           Next

           VertBuffer = New VertexBuffer(GetType(CustomVertex), NUM_VERTS, m_objDevice, Usage.WriteOnly, FVF_CUSTOMVERTEX, Pool.Default)

           Verts = VertBuffer.Lock(0, 0)

           SquareVertices(Verts)

           VertBuffer.Unlock()

           Return True

       Catch objException As Exception

           Return False

       End Try

End Function

Private Function SquareVertices(ByVal Vertices As CUSTOMVERTEX())

       Vertices(0) = CreateFlexVertex(60, 60, 0, 1, 0, 0)
       Vertices(1) = CreateFlexVertex(240, 60, 0, 1, 1, 0)
       Vertices(2) = CreateFlexVertex(60, 240, 0, 1, 0, 1)
       Vertices(3) = CreateFlexVertex(240, 240, 0, 1, 1, 1)

End Function

 Private Function CreateFlexVertex(ByVal X As Single, ByVal Y As Single, ByVal Z As Single, ByVal rhw As Single, _
                                     ByVal tu As Single, ByVal tv As Single) As CUSTOMVERTEX

       CreateFlexVertex.X = X
       CreateFlexVertex.Y = Y
       CreateFlexVertex.Z = Z
       CreateFlexVertex.rhw = rhw
       CreateFlexVertex.tu = tu
       CreateFlexVertex.tv = tv

End Function

 

In the procedure CreateTextures() Verts is declared as CUSTOMVERTEX() which is a structure. So Verts is an array of structures?

 

This line, SquareVertices(Verts), passes Verts to the SquareVertices procedure ByVal again an array of structures?

 

In SquareVertices it assigns values to each array element.

 

But how come the redim staement is not required? I spent a lot of time trying to get this to work and by trial and error found if I removed the redim line it work??

 

Duh.....don't get it :(

[PlausiblyDamp]

the lines

VertBuffer = New VertexBuffer(GetType(CustomVertex), NUM_VERTS, m_objDevice, Usage.WriteOnly, FVF_CUSTOMVERTEX, Pool.Default)
Verts = VertBuffer.Lock(0, 

 

are creating the array at the correct size