[VB.NET]Linee dinamiche...

[Zlatan8.]

Ciao a tutti ho un piccolo problema...Devo disegnare delle linee dinamicamente, cioè clicco una prima volta e fisso il primo punto, poi muovendomi devo vedere la linea muoversi e poi con un secodno click fisso il secondo punto della linea...
Sono da poco passato a vb.net...In vb6 tutto questo lo facevo con il seguente codice:

Dim oldX As Single, oldY As Single
'Array Linee
Dim arrX1(1000) As Single
Dim arrX2(1000) As Single
Dim arrY1(1000) As Single
Dim arrY2(1000) As Single
Dim iNumLinee As Integer

Private Sub Form_Load()
oldX = -1: oldY = -1
End Sub

Private Sub Picture1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If oldX <> -1 Then
Picture2.PaintPicture Picture1.Image, 0, 0
Else
'Aggiunge le coordinate della linea negli array delle linee
arrX1(iNumLinee) = oldX
arrX2(iNumLinee) = X
arrY1(iNumLinee) = oldY
arrY2(iNumLinee) = Y
iNumLinee = iNumLinee + 1
End If
oldX = X
oldY = Y
End Sub

Private Sub Picture1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
If oldX = -1 Then Exit Sub
Picture1.PaintPicture Picture2.Image, 0, 0
Picture1.Line (oldX, oldY)-(X, Y), RGB(0, 0, 0)
End Sub

Ho provato a riadattarlo in vb.net in questo modo ma il risultato è pessimo...

Public Class Form1
    Dim oldX As Single, oldY As Single
    'Array Linee
    Dim arrX1(1000) As Single
    Dim arrX2(1000) As Single
    Dim arrY1(1000) As Single
    Dim arrY2(1000) As Single
    Dim iNumLinee As Integer
    Dim bm As Bitmap

    Private Sub Picture1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Picture1.MouseDown
        If oldX <> -1 Then
            bm = New Bitmap(Picture1.Size.Width, Picture1.Size.Height, Picture1.CreateGraphics())
        Else
            'Aggiunge le coordinate della linea negli array delle linee
            arrX1(iNumLinee) = oldX
            arrX2(iNumLinee) = e.X
            arrY1(iNumLinee) = oldY
            arrY2(iNumLinee) = e.Y
            iNumLinee = iNumLinee + 1
        End If
        oldX = e.X
        oldY = e.Y
    End Sub

    Private Sub Picture1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Picture1.MouseMove
        If oldX = -1 Then Exit Sub
        Picture1.Image = (bm)
        Picture1.CreateGraphics.DrawLine(Pens.Black, oldX, oldY, e.X, e.Y)
    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        oldX = -1 : oldY = -1
    End Sub
End Class

Qualcuno saprebbe aiutarmi?....Grazie mille a tutti...

[Janx]

Cosa significa che il risultato è pessimo?

[Zlatan8.]

Significa intanto che muovendosi la linea si vede molto male, se ci si ferma non si vede e se si clica per fissarla non si vede...

[Pirelli72]

Come al solito si capisce ben poco da quello che scrivi. Comunque sia per disegnare una linea singola:

   Dim pushed As Boolean
    Dim myPoint As PointF
    Dim endPoint As PointF
    Dim bmp As Bitmap

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        bmp = New Bitmap(Me.Width, Me.Height)
    End Sub

    Private Sub Form1_MouseDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseDown
        pushed = True
        myPoint = New PointF(e.X, e.Y)
    End Sub

    Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseMove
        If pushed Then
            endPoint = New PointF(e.X, e.Y)
            Me.Invalidate()
        End If
    End Sub

    Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseUp
        pushed = False
    End Sub

    Private Sub Form1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
        Dim g As Graphics = Graphics.FromImage(bmp)
        g.Clear(Me.BackColor)
        g.SmoothingMode = Drawing2D.SmoothingMode.HighQuality
        g.DrawLine(Pens.Black, myPoint, endPoint)
        e.Graphics.DrawImage(bmp, 0, 0)
    End Sub

[Pirelli72]

Una soluzione che ho complicato al massimo per disegnare più linee insieme..

    Dim pushed As Boolean
    Dim myPoint As PointF
    Dim endPoint As PointF
    Dim count As Integer
    Dim bmp As Bitmap
    Dim myList As New ArrayList
    Dim myLine As Line

    Public Structure Line
        Public startPoint As PointF
        Public endPoint As PointF

        Sub New(ByValstartPoint As PointF, ByVal endPoint As PointF)
            Me.startPoint = startPoint
            Me.endPoint = endPoint
        End Sub
    End Structure

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        bmp = New Bitmap(Me.Width, Me.Height)
    End Sub

    Private Sub Form1_MouseDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseDown
        pushed = True
        myLine = New Line(New PointF(e.X, e.Y), New PointF(e.X, e.Y))
        myList.Add(myLine)
    End Sub

    Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseMove
        If pushed Then
            myLine = CType(myList(count), Line)
            myLine.endPoint = New Point(e.X, e.Y)
            myList.RemoveAt(count)
            myList.Insert(count, myLine)
            Me.Invalidate()
        End If
    End Sub

    Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseUp
        myLine = New Line(myLine.startPoint, New PointF(e.X, e.Y))
        ' myList.Add(myLine)
        pushed = False
        count += 1
        Me.Invalidate()
    End Sub

    Private Sub Form1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
        Dim g As Graphics = Graphics.FromImage(bmp)
        g.Clear(Me.BackColor)
        g.SmoothingMode = Drawing2D.SmoothingMode.HighQuality
        If myList.Count > 0 Then
            For Each linea As Line In myList
                g.DrawLine(Pens.Black, linea.startPoint, linea.endPoint)
            Next
        Else
            g.DrawLine(Pens.Black, myLine.startPoint, myLine.endPoint)
        End If
        e.Graphics.DrawImage(bmp, 0, 0)
    End Sub

[Pirelli72]

Dimenticavo:

 Protected Overrides Sub OnPaintBackground(ByVal e As System.Windows.Forms.PaintEventArgs)
        ' MyBase.OnPaintBackground(e)
    End Sub