GUI doesn't move accordingly - vb.net

Question

i'm trying to display pitch, roll and yaw indications in term of graphic so i build an GUI using user control in visual basic. this is my code for the GUI only.
Private g As Graphics
Private _roll_angle As Double
Public Property roll_angle() As Double
Get
Return _roll_angle
End Get
Set(ByVal value As Double)
_roll_angle = value
Invalidate()
End Set
End Property
Private _pitch_angle As Double
Public Property pitch_angle() As Double
Get
Return _pitch_angle
End Get
Set(ByVal value As Double)
_pitch_angle = value
Invalidate()
End Set
End Property
Private Sub ArtificialHorizon_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
End Sub
Private Function pitch_to_pix(ByVal pitch As Double) As Integer
Return pitch / 35.0 * Me.Height / 2
'Return pitch / 45.0 * Me.Height / 2
End Function
Private Sub ArtificialHorizon_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
g = e.Graphics
g.SmoothingMode = Drawing2D.SmoothingMode.HighQuality
g.Clear(Me.BackColor)
Dim sin As Double = Math.Sin(roll_angle / 180 * 3.14)
g.ResetTransform()
' g.FillRegion(Brushes.White, New Region(New Rectangle(0, 0, Me.Width, Me.Height)))
' rounded rectangle
Dim path As New Drawing2D.GraphicsPath()
Dim r As Single = 50
path.AddArc(0, 0, r, r, 180, 90)
path.AddArc(Me.Width - r, 0, r, r, 270, 90)
path.AddArc(Me.Width - r, Me.Height - r, r, r, 0, 90)
path.AddArc(0, Me.Height - r, r, r, 90, 90)
'path.AddEllipse(0, 0, Me.Width, Me.Height)
path.CloseFigure()
g.SetClip(path)
g.TranslateTransform(Me.Width / 2, Me.Height / 2)
g.RotateTransform(roll_angle)
g.TranslateTransform(0, pitch_to_pix(pitch_angle))
' chocolate
Dim b As New System.Drawing.Drawing2D.LinearGradientBrush(New RectangleF(-Me.Width, 0, Me.Height * 2, Me.Width * 2), Color.FromArgb(255, 219, 140, 21), Color.Brown, Drawing2D.LinearGradientMode.Vertical)
g.FillRectangle(b, New RectangleF(-Me.Width * 2, +1, Me.Height * 4, Me.Width * 4))
g.RotateTransform(180)
' color.aqua
b = New System.Drawing.Drawing2D.LinearGradientBrush(New RectangleF(-Me.Width, -1, Me.Height * 2, Me.Width * 2), Color.FromArgb(255, 28, 134, 186), Color.DarkBlue, Drawing2D.LinearGradientMode.Vertical)
g.FillRectangle(b, New RectangleF(-Me.Width * 2, 0, Me.Height * 4, Me.Width * 4))
g.ResetTransform()
Dim w2 As Single = Me.Width / 2
Dim s As Single = Me.Width / 38
g.TranslateTransform(Me.Width / 2, Me.Height / 2)
g.RotateTransform(45)
g.TranslateTransform(-w2 + s, 0)
g.DrawLine(New Pen(Color.White, 2), 0, 0, s * 2, 0)
g.TranslateTransform(+w2 - s, 0)
g.RotateTransform(15)
g.DrawLine(New Pen(Color.White, 2), -w2 + s, 0, -w2 + s * 2, 0)
g.RotateTransform(15)
g.DrawLine(New Pen(Color.White, 2), -w2 + s, 0, -w2 + s * 2, 0)
g.RotateTransform(15)
g.DrawLine(New Pen(Color.White, 2), -w2 + s, 0, -w2 + s * 3, 0)
'g.DrawString("0°", New System.Drawing.Font("sans-serif", 9), Brushes.White, -w2 + 40, -4)
g.RotateTransform(15)
g.DrawLine(New Pen(Color.White, 2), -w2 + s, 0, -w2 + s * 2, 0)
g.RotateTransform(15)
g.DrawLine(New Pen(Color.White, 2), -w2 + s, 0, -w2 + s * 2, 0)
g.RotateTransform(15)
g.DrawLine(New Pen(Color.White, 2), -w2 + s, 0, -w2 + s * 3, 0)
'g.DrawString("+45°", New System.Drawing.Font("sans-serif", 9), Brushes.White, -w2 + 40, -4)
g.ResetTransform()
Dim length As Single = Me.Width / 4
Dim notch As Single = Me.Width / 30
g.TranslateTransform(Me.Width / 2, Me.Height / 2)
g.DrawLine(New Pen(Color.White, 3), -length + notch * 2, 0, -notch, 0)
g.DrawLine(New Pen(Color.White, 3), notch, 0, length - notch * 2, 0)
g.DrawArc(New Pen(Color.White, 3), -notch, -notch, notch * 2, notch * 2, 180, -180)
g.ResetTransform()
' driehoekje
Dim ww As Single = Me.Width / 38
g.TranslateTransform(Me.Width / 2, Me.Height / 2)
g.RotateTransform(-90 + roll_angle)
path = New Drawing2D.GraphicsPath()
path.AddLine(w2 - ww * 3, 0, w2 - ww * 4, ww)
path.AddLine(w2 - ww * 4, -ww, w2 - ww * 4, ww)
path.AddLine(w2 - ww * 4, -ww, w2 - ww * 3, 0)
g.FillRegion(Brushes.White, New Region(path))
g.DrawLine(New Pen(Color.White, 1), w2 - ww * 3, 0, w2 - ww * 4, ww)
g.DrawLine(New Pen(Color.White, 1), w2 - ww * 4, -ww, w2 - ww * 4, ww)
g.DrawLine(New Pen(Color.White, 1), w2 - ww * 4, -ww, w2 - ww * 3, 0)
g.ResetTransform()
g.ResetClip()
path = New Drawing2D.GraphicsPath()
path.AddPie(New Rectangle(ww * 3, ww * 3, Me.Width - ww * 6, Me.Height - ww * 6), 0, 360)
g.SetClip(path)
g.TranslateTransform(Me.Width / 2, Me.Height / 2)
g.RotateTransform(roll_angle)
g.TranslateTransform(0, pitch_to_pix(pitch_angle))
For i As Integer = -80 To 80 Step 10
drawpitchline(g, i)
Next i
End Sub
Private Sub drawpitchline(ByVal g As Graphics, ByVal pitch As Double)
Dim w As Single = Me.Width / 8
g.DrawLine(Pens.White, -w, pitch_to_pix(-pitch + 5), w, pitch_to_pix(-pitch + 5))
g.DrawLine(Pens.White, -w * 5 / 3, pitch_to_pix(-pitch), w * 5 / 3, pitch_to_pix(-pitch))
g.DrawString(pitch, Me.Font, Brushes.White, -w * 75 / 30, pitch_to_pix(-pitch) - 5)
g.DrawString(pitch, Me.Font, Brushes.White, w * 2, pitch_to_pix(-pitch) - 5)
End Sub
Private Sub drawrollline(ByVal g As Graphics, ByVal a As Single)
Dim w2 As Single = Me.Width / 2
g.RotateTransform(a + 90)
g.TranslateTransform(-w2 + 10, 0)
g.DrawLine(Pens.White, 0, 0, 20, 0)
g.TranslateTransform(10, 5)
g.RotateTransform(-a - 90)
g.DrawString("" & (a) & "°", New System.Drawing.Font("sans-serif", 9), Brushes.White, 0, 0)
g.RotateTransform(+90 + a)
g.TranslateTransform(-10, -5)
g.TranslateTransform(+w2 - 10, 0)
g.RotateTransform(-a - 90)
End Sub
then i added in a button to give some testing readings. code below
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
AH.roll_angle = 45
AH.pitch_angle = 10
End Sub
when the button is clicked, the GUI is supposed to turn/rotate according to the inputs. however, it stays still (btw, code is able to debug thou and the graphic did show up). i believe it's because i did not refer to the AH variable in my painting. can someone pls give me a guide on this?
thanks in advance!

Answer 1

I might have something which can be used, I created this to display azimuth heading of parabolic antenna.
the heading is using simple pen
superimpose on top of circle image
the pen will rotate according to the degree movement
With 3 main functions
DrawAntenna() --> draw the pen/line
FindPointOnCircle() --> find end point of the pen (start point always center of circle)
RotateAntenna() --> this will rotate the pen and updating the image accordingly
call RotateAntenna from your function (e.g. TextChanged), and pass the change angle to RotateAntenna
One key thing is to do a refresh on the image whenever the angle change, this will provide rotate effect.
I suggest making this on a different thread, as not to bogged down your main thread, because usually this data acquisition for the azm/elv/roll will happen continuously.
Down to the code:
Private Function FindPointOnCircle(ByVal originPoint As Point, ByVal radius As Double, ByVal angleDegrees As Double) As Point
Dim x As Double = radius * Math.Cos(Math.PI * angleDegrees / 180.0) + originPoint.X
Dim y As Double = radius * Math.Sin(Math.PI * angleDegrees / 180.0) + originPoint.Y
Return New Point(x, y)
End Function
Private Sub DrawAntenna(ByVal originPoint As Point, ByVal endPoint As Point, ByVal g As Graphics, Optional ByVal aPen As Pen = Nothing)
If aPen Is Nothing Then
Using BluePen = New Pen(Color.Blue)
BluePen.Width = 2
g.DrawLine(BluePen, originPoint.X, originPoint.Y, endPoint.X, endPoint.Y)
End Using
Else
g.DrawLine(aPen, originPoint.X, originPoint.Y, endPoint.X, endPoint.Y)
End If
End Sub
Private Sub RotateAntenna(ByVal ang As Double, ByVal g As Graphics, ByVal typeOfDisplay As Integer)
' Radius of 95% of half the width of the panel
Dim radius As Double = (Me.picDestTop.Width / 2) * 0.95
' Origin half of width and height of panel
Dim origin As New Point(Me.picDestTop.Width / 2, Me.picDestTop.Height / 2)
Select Case typeOfDisplay
Case displayAntenna.DisplayTop
'rotate start at 270deg, pointing up
Dim antennaDegrees As Double = ang + 170
'find point
Dim secondsPoint As Point = FindPointOnCircle(origin, radius, antennaDegrees)
Using p As New Pen(Color.Red)
p.Width = 5
DrawAntenna(origin, secondsPoint, g, p)
End Using
Case displayAntenna.DisplaySide
'display elevation
Case displayAntenna.DisplayRoll
'display pitch
End Select
g.Dispose()
End Sub
'azimuth
Private Sub lblEncCurrent_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lblEncCurrent.TextChanged
Dim iint As Double
Me.picDestTop.Refresh()
iint = CDbl(lblEncCurrent.Text)
If iint >= 360 Then
iint = iint - 360
End If
RotateAntenna(iint, Me.picDestTop.CreateGraphics, displayAntenna.DisplayTop)
End Sub
Hope this help!!. Thanks.