[RESOLVED] MSchart Scaling and Moving Multiple Data Points

[Frabulator]

---- EDIT 2/10/2015 ----

I have successfully completed my task of Manipulating, Scaling and relocating multiple values in an MSChart in VB.Net code. I needed to use a formula method, which is typed below in comment 7 (I think), which took me several days of calculating to come up with.

Everything is done through data binding, fraction scaling, and mathematical equations with loops. I have a mouse down, mouse up, mouse click and mouse move event in order to capture all of these.

BUT!!! My question still remains the same. Is there an easier way to do this?!? This has been going for almost a week (I think) and still no answers.

Thanks everyone !!!!





---- EDIT 2/8/2015 ----

Well I have answered one of my own questions, which is the relocation of the data points. I figured out after days of smacking my head that I needed to use the MouseClick event instead of the MouseDown event to grab two data points (Duh). But with that information I was able to loop through the data points and move them based on the difference between the old end point and the new location (by math functions).

So, only thing left is my last question. Which, like I stated before, I have an equation for, its just working out out. Is it still feasible or is there a better way?


---- END EDIT ----


CURRENTLY ALL ANSWERED

I have a chart that populates from a collection of data in a DataGridView in which its binded. I have many points which need to be selected with either a loop (select point A and point B) or a transparent box drawing (all points within that range). Once selected they need to do two things, to be able to click on selected points and drag all of them to another position on the Y axis (first set of images) or scale the selected points (shown in second images).

I have the code complete so I can drag/drop and manipulate the position of one point, so I know that the loop method (selecting the start point and end point) would work for relocating each point in that range. My first problem is I don’t know how to select a multi range and loop through them. I have tried the normal loop methods, but I cannot seem to get it to work at all. I think I am doing it completely wrong so I scrapped my loop code and brought it here.

First question:
1. How do I set up a loop for datapoints in a spline/line/fastline graph in MSChart?

COMPLETE

My next problem is scaling the selected points like in the second set of images? I thought I could do it with a math equation, something like:

            Dim i As Integer
            Dim x As Integer
            Dim scaleRation As Integer = 0.05

            Dim NumberOfPoints As Integer
            NumberOfPoints = 1

            For i = StartPoint To EndPoint
                NumberOfPoints = NumberOfPoints + 1
            Next

            For x = StartPoint To EndPoint
                x = x * (scaleRation / NumberOfPoints)
            Next

Of course that is not working code, but the concept is there. A math function of “x * (1/(however many points))” and then the next would be “x * (2/(however many points))” and so on so that it would scale each loop perspectival.

Second question:
2. Can my code (well, more like idea) work, and is there an easier way to do this that I have overlooked?

COMPLETE





The code that I am currently using to manipulate individual points on the chart is listed below. I am using a Mousedown, MouseMove and Mouseup combined with HitTest to select one point and move it on the Y axis.

Public Class Form1






    Dim dtG2 As DataTable


    Dim pointIndex As Integer
    Dim pointIndexstart As Integer
    Dim pointIndexend As Integer


    Private selectedDataPoint As DataPoint = Nothing
    Private selectedDataPointStart As DataPoint = Nothing
    Private selectedDataPointEnd As DataPoint = Nothing
    Private selectedDataPoints As DataPointCollection = Nothing




    Dim htrResult As HitTestResult = Nothing
    Dim htrResult2 As HitTestResult = Nothing


    '/ <summary>
    '/ Mouse Down Event
    '/ </summary>
    Private Sub Chart3_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Chart3.MouseDown
        ' Call Hit Test Method


        'checks to see if curser is on
      

                'Go through points setting design elements back to default


                If e.Button = MouseButtons.Right Then

                    Dim hitResult As HitTestResult = Chart3.HitTest(e.X, e.Y)


                    ' Initialize currently selected data point
                    selectedDataPoint = Nothing
                    If hitResult.ChartElementType = ChartElementType.DataPoint Then
                        selectedDataPoint = CType(hitResult.Object, DataPoint)
                        pointIndex = Chart3.Series(1).Points.IndexOf(selectedDataPoint)

                        ' Show point value as label
                        selectedDataPoint.IsValueShownAsLabel = True

                        ' Set cursor shape
                        Chart3.Cursor = Cursors.SizeNS
                    End If
                End If







    End Sub 'Chart1_MouseDown

    Private Sub Chart3_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Chart3.MouseMove
        ' Check if data point selected


            If Not (selectedDataPoint Is Nothing) Then
                ' Mouse coordinates should not be outside of the chart 
                Dim coordinate As Integer = e.Y
                If coordinate < 0 Then
                    coordinate = 0
                End If
                If coordinate > Chart3.Size.Height - 1 Then
                    coordinate = Chart3.Size.Height - 1
                End If
                ' Calculate new Y value from current cursor position
                Dim yValue As Double = Chart3.ChartAreas(0).AxisY.PixelPositionToValue(coordinate)
                yValue = Math.Min(yValue, Chart3.ChartAreas(0).AxisY.Maximum)
                yValue = Math.Max(yValue, Chart3.ChartAreas(0).AxisY.Minimum)

                ' Update selected point Y value
                selectedDataPoint.YValues(0) = yValue
                Try


                    dtG2.Rows(pointIndex).Item("MD") = yValue
                Catch ex As Exception

                End Try
                ' Invalidate chart
                Chart3.Invalidate()



            Else
                ' Set different shape of cursor over the data points
                Dim hitResult As HitTestResult = Chart3.HitTest(e.X, e.Y)
                If hitResult.ChartElementType = ChartElementType.DataPoint Then
                    Chart3.Cursor = Cursors.Hand
                Else
                    Chart3.Cursor = Cursors.Default
                End If
            End If

    End Sub

    '/ <summary>
    '/ Mouse Up Event
    '/ </summary>
    Private Sub Chart3_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Chart3.MouseUp
        ' Initialize currently selected data point
      
            If Not (selectedDataPoint Is Nothing) Then
                ' Hide point label
                selectedDataPoint.IsValueShownAsLabel = False

                ' reset selected object
                selectedDataPoint = Nothing

                ' Invalidate chart
                Chart3.Invalidate()

                ' Reset cursor style
                Chart3.Cursor = Cursors.Default


        End If


    End Sub 'Chart1_MouseUp

Moving selected data points to new location (complete)




resizing and scaling selected data points (Complete)



Thanks for the help!