3D Histogram Example

This is an example for creating a 3D Histogram using GDI+ in VB.Net (and c# added 17/7/2015)

Attachment 127787

All of the drawing is done with Transforms in the PictureBox_Paint event, and the Histogram has MouseOver features:

Code:

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Private Sub PictureBox1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
    If propertiesDictionary("Total Income") <> 0 Then

        Dim totalHeight As Integer = CInt(propertiesDictionary("Total Income"))
        Dim topHeight As Integer = CInt(totalHeight * 0.05)

        ' Flip vertically and scale to fit.
        Dim scalex As Single = 20.0F
        Dim scaley As Single = CSng(-PictureBox1.Height / (totalHeight * 1.5))
        e.Graphics.ScaleTransform(scalex, scaley, MatrixOrder.Append)

        ' Translate so (0, MAX_VALUE) maps to the origin.
        e.Graphics.TranslateTransform(0, PictureBox1.Height, MatrixOrder.Append)

        Dim front() As PointF = { _
        New PointF(0, 0), _
        New PointF(0, totalHeight), _
        New PointF(2, totalHeight), _
        New PointF(2, 0), _
        New PointF(0, 0) _
        }

        Dim top() As PointF = { _
            New PointF(0, totalHeight), _
            New PointF(1, totalHeight + topHeight), _
            New PointF(3, totalHeight + topHeight), _
            New PointF(2, totalHeight), _
            New PointF(0, totalHeight) _
        }

        Dim right() As PointF = { _
            New PointF(2, totalHeight), _
            New PointF(3, totalHeight + topHeight), _
            New PointF(3, topHeight), _
            New PointF(2, 0), _
            New PointF(2, totalHeight) _
        }

        ' Draw the histogram.
        For x As Integer = 0 To propertiesDictionary.Count - 1
            rgns(x) = New GraphicsPath
            Dim value As Integer = CInt(propertiesDictionary.ElementAt(x).Value)
            If value > 0 Then
                Dim offsetX As Single = CSng(x * 2.5)

                Dim barFront() As PointF = Array.ConvertAll(front, Function(pf) New PointF(pf.X + offsetX, pf.Y))
                barFront(1).Y = value
                barFront(2).Y = value
                e.Graphics.FillPolygon(New SolidBrush(barColors(x)), barFront)
                e.Graphics.DrawPolygon(New Pen(Color.Black, 0), barFront)
                rgns(x).AddPolygon(Array.ConvertAll(barFront, Function(pf) New PointF(pf.X * scalex, pf.Y * scaley)))

                Dim barTop() As PointF = Array.ConvertAll(top, Function(pf) New PointF(pf.X + offsetX, value))
                barTop(1).Y += topHeight
                barTop(2).Y += topHeight
                e.Graphics.FillPolygon(New SolidBrush(barColors(x)), barTop)
                e.Graphics.DrawPolygon(New Pen(Color.Black, 0), barTop)

                rgns(x).AddPolygon(Array.ConvertAll(barTop, Function(pf) New PointF(pf.X * scalex, pf.Y * scaley)))

                Dim barRight() As PointF = Array.ConvertAll(right, Function(pf) New PointF(pf.X + offsetX, pf.Y))
                barRight(0).Y = value
                barRight(1).Y = value + topHeight
                barRight(4).Y = value
                e.Graphics.FillPolygon(New SolidBrush(barColors(x)), barRight)
                e.Graphics.DrawPolygon(New Pen(Color.Black, 0), barRight)

                rgns(x).AddPolygon(Array.ConvertAll(barRight, Function(pf) New PointF(pf.X * scalex, pf.Y * scaley)))

            End If
        Next

        e.Graphics.ResetTransform()

    Else
        Array.Clear(rgns, 0, 10)
    End If
End Sub

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Download example project: here (c# added 17/7/2015)

Looking nice... It's useful... Thanks ;)

Improved version available here...

http://www.scproject.biz/Household_Budgets.php

Thanks paul