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I'm making a simple game application that based on DirectX.

'Provide:  the transform matrix for each sprite, the width and height of each
'  color map, and the color map (here called the "alpha map")
Public Shared Function PixelIntersects(ByVal transformA As Microsoft.DirectX.Matrix, ByVal widthA As Integer, ByVal heightA As Integer, ByVal alphaMapA() As Byte, _
                                    ByVal transformB As Microsoft.DirectX.Matrix, ByVal widthB As Integer, ByVal heightB As Integer, ByVal alphaMapB() As Byte) As Boolean

    'Create a matrix that transforms matrix A relative to matrix B
    Dim transformAToB As Microsoft.DirectX.Matrix = transformA * Microsoft.DirectX.Matrix.Invert(transformB)

    'for each row in A
    For yA As Integer = 0 To heightA - 1
        'for each pixel in row in A
        For xA As Integer = 0 To widthA - 1

            ' Get the pixel position of the B object relative to the A object
            Dim posInB As Microsoft.DirectX.Vector2 = Microsoft.DirectX.Vector2.TransformCoordinate(New Microsoft.DirectX.Vector2(xA, yA), transformAToB)

            If Single.IsNaN(posInB.X) Then Continue For
            If Single.IsNaN(posInB.Y) Then Continue For

            ' Convert to an integer position
            Dim xB As Integer = Convert.ToInt32(Math.Round(posInB.X))
            Dim yB As Integer = Convert.ToInt32(Math.Round(posInB.Y))

            ' First determine if xB, yB is within the rectangle bounds of the A object
            If xB >= 0 And xB < widthB And yB >= 0 And yB < heightB Then

                ' Get the alpha value of the A and B object
                Dim alphaA As Byte = alphaMapA(yA * widthA + xA)
                Dim alphaB As Byte = alphaMapB(yB * widthB + xB)

                ' If the alpha value of the point in the A object and the B object is greater than zero
                ' (zero = completely transparent) then a pixel intersection has occured and return true
                If alphaA > 0 And alphaB > 0 Then
                    Return True
                End If

            End If


    ' Looped through the objects with no pixel intersections
    Return False

End Function

I googled my problem and I found this function.

But this isn't work :(

How to detect collision of rotated 2D sprite in DirectX(No XNA)?

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