Public Sub TransformVectorsExample(ByVal e As PaintEventArgs)
Dim myPen As New Pen(Color.Blue, 1)
Dim myPen2 As New Pen(Color.Red, 1)
' Create an array of points.
Dim myArray As Point() = {New Point(20, 20), New Point(120, 20), _
New Point(120, 120), New Point(20, 120), New Point(20, 20)}
' Draw the Points to the screen before applying the
' transform.
e.Graphics.DrawLines(myPen, myArray)
' Create a matrix and scale it.
Dim myMatrix As New Matrix
myMatrix.Scale(3, 2, MatrixOrder.Append)
myMatrix.Translate(100, 100, MatrixOrder.Append)
ListMatrixElementsHelper(e, myMatrix, _
"Scaled and Translated Matrix", 6, 20)
myMatrix.TransformVectors(myArray)
' Draw the Points to the screen again after applying the
' transform.
e.Graphics.DrawLines(myPen2, myArray)
End Sub
' A helper function to list the contents of a matrix.
Public Sub ListMatrixElementsHelper(ByVal e As PaintEventArgs, _
ByVal matrix As Matrix, ByVal matrixName As String, ByVal numElements As Integer, _
ByVal y As Integer)
' Set up variables for drawing the array
' of points to the screen.
Dim i As Integer
Dim x As Single = 20
Dim j As Single = 200
Dim myFont As New Font("Arial", 8)
Dim myBrush As New SolidBrush(Color.Black)
' Draw the matrix name to the screen.
e.Graphics.DrawString(matrixName + ": ", myFont, myBrush, x, y)
' Draw the set of path points and types to the screen.
For i = 0 To numElements - 1
e.Graphics.DrawString(matrix.Elements(i).ToString() + ", ", _
myFont, myBrush, j, y)
j += 30
Next i
End Sub
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