有没有办法在 VB.net 中将像素坐标转换为笛卡尔坐标

我有一个大小为 1096 x 1004 的 PictureBox，SizeMode 设置为 StretchImage。通过考虑像素坐标上的 StrechImage 效果，我能够正确获取每个像素的坐标（请参阅下面的代码）。

现在我想要完成的是将这些像素坐标转换为笛卡尔坐标以便能够绘制图形。从长远来看，我将采用笛卡尔坐标并将它们转换为极坐标。

我尝试使用这种方法将像素坐标转换为笛卡尔坐标。

cartesianx = scalefactor*screenx - screenwidth / 2;
cartesiany = -scalefactor*screeny + screenheight / 2;

此方法不是将原点放在 (0,0) 处的图片框的中心。它似乎将原点设置为靠近图片框的左上角。对我缺少什么有任何想法吗？

下面是我将图像转换为 BitMap 并获取这些坐标并正确缩放它们的代码。

Imports System.IO

Public Class HomePanel

Dim realX As Int32
Dim realY As Int32

Private Sub HomePanel_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    chartImageDisplay_box.Image = Image.FromFile("C:\Users\UserB\Desktop\test.jpg")

End Sub


Private Sub chartImageDisplay_box_MouseMove(sender As Object, e As MouseEventArgs) Handles chartImageDisplay_box.MouseMove

    If (e.Button = MouseButtons.Left) Then
        ShowCoords(e.X, e.Y)
    End If

End Sub



Private Sub chartImageDisplay_box_MouseDown(sender As Object, e As MouseEventArgs) Handles chartImageDisplay_box.MouseDown
    If (e.Button = MouseButtons.Left) Then
        ShowCoords(e.X, e.Y)

        Dim MyBitmap As Bitmap
        MyBitmap = CType(chartImageDisplay_box.Image, Bitmap)
        'Me.BackColor = MyBitmap.GetPixel(realX, realY)
        rgbValue.Text = "RGB Value: " & MyBitmap.GetPixel(realX, realY).ToString()

    End If
    'printAllPixels()

End Sub


Private Sub ShowCoords(ByVal mouseX As Int32, ByVal mouseY As Int32)
    Dim realW As Int32 = chartImageDisplay_box.Image.Width
    Dim realH As Int32 = chartImageDisplay_box.Image.Height
    Dim currentW As Int32 = chartImageDisplay_box.ClientRectangle.Width
    Dim currentH As Int32 = chartImageDisplay_box.ClientRectangle.Height
    Dim zoomW As Double = (currentW / CType(realW, Double))
    Dim zoomH As Double = (currentH / CType(realH, Double))
    Dim zoomActual As Double = Math.Min(zoomW, zoomH)
    Dim padX As Double = If(zoomActual = zoomW, 0, (currentW - (zoomActual * realW)) / 2)
    Dim padY As Double = If(zoomActual = zoomH, 0, (currentH - (zoomActual * realH)) / 2)
    realX = CType(((mouseX - padX) / zoomActual), Int32)
    realY = CType(((mouseY - padY) / zoomActual), Int32)
    lblPosXval.Text = "X: " & If(realX < 0 OrElse realX > realW, "-", realX.ToString())
    lblPosYVal.Text = "Y: " & If(realY < 0 OrElse realY > realH, "-", realY.ToString())
    cartX.Text = "X: " 'Where to add the cart conversion for X
    cartY.Text = "Y: " 'Where to add the cart conversion for Y

End Sub


'Writes all the pixels to a text file along with RGB values for each pixel
Public Sub printAllPixels()
    Using writer As StreamWriter =
        New StreamWriter("C:\Users\UserB\Desktop\Pixels.txt")

        Dim MyBitmap As Bitmap
        MyBitmap = CType(chartImageDisplay_box.Image, Bitmap)


        For y = 0 To MyBitmap.Height - 1
            For x = 0 To MyBitmap.Width - 1
                writer.WriteLine("XY Coord: " & x & ", " & y & ";   " & MyBitmap.GetPixel(x, y).ToString)
            Next
        Next


    End Using
End Sub
End Class