Imports System
Imports System.IO
Imports System.Drawing.Drawing2D
Imports GeomLib.GeomLib
Public Class GraphicsViewer
' data members
Private arlPoints As New ArrayList
Private UpperLimit As New Point3D
Private LowerLimit As New Point3D
Private TransMat As New Matrix3D
Private Sub OpenDataFileToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenDataFileToolStripMenuItem.Click
TransMat.SetToIdentity()
' open the points data file
' read the points and store them in the data member
OpenFileDialog1.Title = "Open Point Data File"
OpenFileDialog1.Filter = "Point Data Files (*.txt)|*.txt|All Files(*.*)|*.*"
OpenFileDialog1.FileName = ""
Dim strFileName As String
If OpenFileDialog1.ShowDialog() = Windows.Forms.DialogResult.OK Then
strFileName = OpenFileDialog1.FileName
Else
Exit Sub ' if user has cancelled
End If
Dim blnFileRead As Boolean
blnFileRead = PointReader(strFileName)
If Not blnFileRead Then Exit Sub ' if not a valid data file
' set the upper and lower limits
LLimit()
ULimit()
' set the default view to 3D
View3DToolStripMenuItem_Click(sender, e)
' refresh the drwing area
PanelDraw.Invalidate()
End Sub
Private Sub ViewFromXToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ViewFromXToolStripMenuItem.Click
' set the drawing tp initial position (looking from Z)
Dim Mat As New Matrix3D
Mat = TransMat.GetInverse
TransformPoints(Mat)
TransMat.PostMultiplyBY(Mat)
Mat.SetToIdentity()
' create a matrix with the required rotation
Mat.SetToRotation(90 * Math.PI / 180.0, New Vector3D(0, 1, 0))
' and transorm the points
TransformPoints(Mat)
' update the matrix data member
TransMat.PostMultiplyBY(Mat)
' refresh the drwing area
PanelDraw.Invalidate()
End Sub
Private Sub ViewFromYToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ViewFromYToolStripMenuItem.Click
' set the drawing tp initial position (looking from Z)
Dim Mat As New Matrix3D
Mat = TransMat.GetInverse
TransformPoints(Mat)
TransMat.PostMultiplyBY(Mat)
Mat.SetToIdentity()
' create a matrix with the required rotation
Mat.SetToRotation(90 * Math.PI / 180.0, New Vector3D(1, 0, 0))
' and transorm the points
TransformPoints(Mat)
' update the matrix data member
TransMat.PostMultiplyBY(Mat)
' refresh the drwing area
PanelDraw.Invalidate()
End Sub
Private Sub ViewFromZToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ViewFromZToolStripMenuItem.Click
' set the drawing tp initial position (looking from Z)
Dim Mat As New Matrix3D
Mat = TransMat.GetInverse
' and transorm the points
TransformPoints(Mat)
' update the matrix data member
TransMat.PostMultiplyBY(Mat)
Mat.SetToIdentity()
' create a matrix with the required rotation
Mat.SetToRotation(-90 * Math.PI / 180.0, New Vector3D(0, 0, 1))
' and transorm the points
TransformPoints(Mat)
' update the matrix data member
TransMat.PostMultiplyBY(Mat)
' refresh the drwing area
PanelDraw.Invalidate()
End Sub
Private Sub View3DToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles View3DToolStripMenuItem.Click
' set the drawing tp initial position (looking from Z)
Dim Mat As New Matrix3D
Mat = TransMat.GetInverse
TransformPoints(Mat)
TransMat.PostMultiplyBY(Mat)
' create the required rotation matrix, transform the points and
' refresh the drawing area
Dim xMat As New Matrix3D
Dim temp As New Matrix3D
temp.SetToRotation(45 * Math.PI / 180.0, New Vector3D(1, 0, 0))
xMat.PostMultiplyBY(temp)
temp.SetToIdentity()
temp.SetToRotation(135 * Math.PI / 180.0, New Vector3D(0, 1, 0))
xMat.PostMultiplyBY(temp)
temp.SetToIdentity()
temp.SetToRotation(-45 * Math.PI / 180.0, New Vector3D(0, 0, 1))
xMat.PostMultiplyBY(temp)
TransformPoints(xMat)
TransMat.PostMultiplyBY(xMat)
PanelDraw.Invalidate()
End Sub
Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click
Me.Close()
End Sub
Private Function PointReader(ByVal FileName As String) As Boolean
'read the points from the data file and set the points
' to the array variable (data member)
arlPoints.Clear()
If File.Exists(FileName) Then
Dim ioFile As New StreamReader(FileName)
Dim ioLine As String
ioLine = ioFile.ReadLine
' if file exists and a valid file...
If InStr(ioLine, " ") = 0 Then
MsgBox("Not a Valid File.", MsgBoxStyle.Information, "Open Data File")
PointReader = False
Exit Function
Else
If Not (IsNumeric(Trim(Mid(ioLine, 1, InStr(ioLine, " "))))) Then
MsgBox("Not a Valid File.", MsgBoxStyle.Information, "Open Data File")
PointReader = False
Exit Function
End If
End If
Me.Cursor = Cursors.WaitCursor
' read line by line and set the points
While ioLine <> ""
Dim ptX, ptY, ptZ As Double
ReadPointFromString(ioLine, ptX, ptY, ptZ)
Dim Pnt As New Point3D
Pnt.X = ptX
Pnt.Y = ptY
Pnt.Z = ptZ
arlPoints.Add(Pnt)
ioLine = ioFile.ReadLine
End While
Me.Cursor = Cursors.Default
Return True
Else
Me.Cursor = Cursors.Default
Return False
End If
Me.Cursor = Cursors.Default
Return False
End Function
Private Sub ReadPointFromString(ByVal strPoint As String, ByRef ptX As Double, ByRef ptY As Double, ByRef ptZ As Double)
' take a string that consists of x, y and z points
' example 50.0 25.0 35.0 (x, y & z separated by spaces)
Dim intSpacePos As Integer
intSpacePos = InStr(strPoint, " ")
ptX = Trim(Mid(strPoint, 1, intSpacePos))
strPoint = Trim(Mid(strPoint, Trim(intSpacePos)))
intSpacePos = InStr(strPoint, " ")
ptY = Trim(Mid(strPoint, 1, intSpacePos))
strPoint = Trim(Mid(strPoint, Trim(intSpacePos)))
ptZ = Trim(strPoint)
End Sub
Private Sub PanelDraw_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles PanelDraw.Paint
' set the lower limit and upper limit of the bounding box
LLimit()
ULimit()
Dim SF As Single
Dim X1, X2, Y1, Y2 As Single
X1 = LowerLimit.X * 1.5
Y1 = LowerLimit.Y * 1.5
X2 = UpperLimit.X * 1.5
Y2 = UpperLimit.Y * 1.5
Dim CX, CY As Single
CX = X1 + (X2 - X1) / 2
CY = Y1 + (Y2 - Y1) / 2
' calculate the scale factor of the drawing, that is to be displayed
' based on the bounding box
If PanelDraw.Width / (X2 - X1) < PanelDraw.Height / (Y2 - Y1) Then
SF = Fix((PanelDraw.Width / (X2 - X1)))
If X2 = 0.0 And X1 = 0.0 Then SF = 1.0
Else
SF = Fix((PanelDraw.Height / (Y2 - Y1)))
If Y2 = 0.0 And Y1 = 0.0 Then SF = 1.0
End If
If SF = 0.0 Then SF = 1.0
Dim sTransform As New Matrix
' center the drawing
e.Graphics.TranslateTransform((PanelDraw.Width / 2 + CX), (PanelDraw.Height / 2 + CY))
' we want Y upwards. by default Y points downwards from top left corner
' change that to point upwards from bottom left corner
e.Graphics.RotateTransform(180)
' transform to scale
e.Graphics.ScaleTransform(SF, SF)
' draw the required lines
Dim Pt As New Point3D
Dim i As Integer = 1
Dim Pt1 As New Point3D
For i = 0 To arlPoints.Count - 2
Pt = arlPoints(i)
Pt1 = arlPoints(i + 1)
e.Graphics.DrawLine(Pens.AliceBlue, CSng(Pt.X), CSng(Pt.Y), CSng(Pt1.X), CSng(Pt1.Y))
Next
End Sub
' find the lower limit of the bounding box (lower left corner)
Public Sub LLimit()
Dim Pt As New Point3D
Dim i As Integer = 0
For Each Pt In arlPoints
If i = 0 Then
LowerLimit.SetPoint(Pt.X, Pt.Y, Pt.Z)
End If
If Pt.X < LowerLimit.X Then LowerLimit.X = Pt.X
If Pt.Y < LowerLimit.Y Then LowerLimit.Y = Pt.Y
If Pt.Z < LowerLimit.Z Then LowerLimit.Z = Pt.Z
i += 1
Next
End Sub
' find the upper limit of the bounding box (upper right corner)
Public Sub ULimit()
Dim Pt As New Point3D
Dim i As Integer = 0
For Each Pt In arlPoints
If i = 0 Then
UpperLimit.SetPoint(Pt.X, Pt.Y, Pt.Z)
End If
If Pt.X > UpperLimit.X Then UpperLimit.X = Pt.X
If Pt.Y > UpperLimit.Y Then UpperLimit.Y = Pt.Y
If Pt.Z > UpperLimit.Z Then UpperLimit.Z = Pt.Z
i += 1
Next
End Sub
' transform the points by the given matrix
Public Sub TransformPoints(ByVal Mat As Matrix3D)
Dim Pt As New Point3D
For Each Pt In arlPoints
Pt.TransformBy(Mat)
Next
End Sub
End Class
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