Finding a rounded coordinate in a rotated view along Element, MST8i SS4, VBA

Mikha Zaslavskiy said:

I'm drawing a square in rotated View and want to create horizontal lines

Horizontal with respect to the View, or horizontal with respect to the coordinate system?

Mikha Zaslavskiy said:

Each line must start with a rounded X-Coordinate

1. Create a line aligned with the Y axis
2. Move the X coordinates: pt.X = CDbl(CLong(1000.0 * pt.X) / 1000)
3. Rotate the line by the inverse of the View rotation
4. Add the line to the active model

Create a line aligned with the X axis:

PntZusatz = Origin 
PntZus2 = Point3dAddScaled(Origin, Xv, 1000)
PntZus2.X = Runden(CDbl(CLng(PntZusatz.X)), -2)
Axis = Point3dFromXYZ(1, 0, 0)

oMatrix = Matrix3dFromVectorAndRotationAngle(Axis, dAngle)
Set TmpVertLine = CreateLineElement2(Nothing, PntZusatz, PntZus2)
oTransform = Transform3dFromMatrix3dAndFixedPoint3d(oMatrix, Origin)
TmpVertLine.Transform oTransform

Create a line aligned with the X axis:

PntZusatz = Origin 
PntZus2 = Point3dAddScaled(Origin, Xv, 1000)
PntZus2.X = Runden(CDbl(CLng(PntZusatz.X)), -2)
Axis = Point3dFromXYZ(1, 0, 0)

oMatrix = Matrix3dFromVectorAndRotationAngle(Axis, dAngle)
Set TmpVertLine = CreateLineElement2(Nothing, PntZusatz, PntZus2)
oTransform = Transform3dFromMatrix3dAndFixedPoint3d(oMatrix, Origin)
TmpVertLine.Transform oTransform

Mikha Zaslavskiy said:

Is it correct?

No idea!  I have difficulty visualising what you want to do.  Perhaps it would help if you draw manually what you want to achieve, then post the DGN file here?

I have posted a Picture. Thanks for your Time.

Hi Mikha,

the problem is that your picture is not well connected to the code.

Plus, when you do not bother to share a code in a proper way (to use Insert > Insert Code tool to ensure it will be displayed as the code), I assume not many people is willing to invest time to analyze the problem.

Another problem is that you are trying to solve two different problems in one step:

• How to work in rotated view
• How to implement specific rounding

I recommend to implement the rounding at first (for not rotated view, so there will be no matrices used) and provide more complete code, that can be tested (it means it has to be sub, containing input values and some output). It allows to move from pure theory to something testable.

When it will work, it makes sense to start another discussion how to extend the code to work in rotated view.

With regards,

  Jan

1. Create your geometry using unrotated Cartesian coordinates
2. Determine your target point
3. Group the elements into a cell: the origin of your cell is your target point
4. Rotate the cell about its origin (your target point) by the inverse view rotation
5. Drop the cell and add its components to your active DGN model

I will follow your Recommendations Jan and prepare a Code for a Rounding in unrotated View. 

This is my Code for unrotated View. In This case i need round Y-Coordinates.

Option Explicit
Option Base 0

Implements IPrimitiveCommandEvents

Dim k As Long, nPnts As Long
Dim Origin As Point3d                               'Ursprungpunkt
Dim obAccudrawAn As Boolean
Dim PtsShapInnen() As Point3d                       'Punkte zur Bildung Fläche des Zaunes
Dim Plane As Plane3d                                'Projektion auf Plan
Dim Rot As Matrix3d, Hyp As Double                  'Matrize zur Ansicht, Hypotenuse zw. Ursprung und Point
Dim DoubleX As Double, DoubleY As Double            'Katheten
Dim Xv As Point3d, Yv As Point3d                    'Projektion auf X,Y-Achsen
Dim Alfa As Double, Beta As Double, dAngle As Double         'Winkeln
Dim Sh As element, LineLinkeKo() As LineElement


Private Sub IPrimitiveCommandEvents_DataPoint(Point As Point3d, ByVal View As View)
If nPnts = 0 Then
    Origin = Point
    Plane.Origin = Point
    nPnts = nPnts + 1
    CommandState.StartDynamics
Else
    CommandState.StopDynamics
    CommandState.StartDefaultCommand
    If Not Sh Is Nothing Then Sh.Level = ActiveSettings.Level: ActiveModelReference.AddElement Sh
    For k = LBound(LineLinkeKo) To UBound(LineLinkeKo)
        If Not LineLinkeKo(k) Is Nothing Then LineLinkeKo(k).Level = ActiveSettings.Level: ActiveModelReference.AddElement LineLinkeKo(k)
    Next k
End If
End Sub

Private Sub IPrimitiveCommandEvents_Dynamics(Point As Point3d, _
 ByVal View As View, ByVal DrawMode As MsdDrawingMode)

On Error GoTo err
If DrawMode = msdDrawingModeTemporary Then
    'Ansichtdrehung auslesen
     If CommandState.AccuDrawHints.IsEnabled Then
        Rot = Matrix3dInverse(CommandState.AccuDrawHints.GetRotation(View))    'Matrix3dInverse
     Else
        Rot = Matrix3dInverse(View.Rotation)
     End If
     If Matrix3dIsXYRotation(View.Rotation, dAngle) Then
     End If
     
     'auf Plan projezieren
     Plane.Normal = Point3dFromMatrix3dColumn(Rot, 2)
     Xv = Point3dFromMatrix3dColumn(Rot, 0)
     Yv = Point3dFromMatrix3dColumn(Rot, 1)
     Point = Point3dProjectToPlane3d(Point, Plane)
     Hyp = Point3dDistance(Point, Origin)
     
     Alfa = Point3dAngleBetweenVectors(Xv, Point3dSubtract(Point, Origin))
     Beta = Point3dAngleBetweenVectors(Yv, Point3dSubtract(Point, Origin))
    
'     If (Alfa > (135 * Pi / 180)) Or (Beta > (135 * Pi / 180)) Or (Beta > 1.5) Or (Alfa > 1.5) Then Exit Sub
    
     ReDim PtsShapInnen(0 To 3)
     PtsShapInnen(0) = Origin
     PtsShapInnen(1) = Point3dAddScaled(Origin, Xv, Hyp * Cos(Alfa))
     PtsShapInnen(2) = Point
     PtsShapInnen(3) = Point3dAddScaled(Origin, Yv, Hyp * Cos(Beta))
     Set Sh = CreateShapeElement1(Nothing, PtsShapInnen, msdFillModeNotFilled)
    
     'Rahmen als Rechteck erstellen
     If dAngle = 0 Then Call CreateLinesRounded(View, Origin)

    'Breite/Höhe
     DoubleX = Point3dDistanceXY(PtsShapInnen(0), PtsShapInnen(1))
     DoubleY = Point3dDistanceXY(PtsShapInnen(0), PtsShapInnen(3))
End If

Sh.Redraw DrawMode
For k = LBound(LineLinkeKo) To UBound(LineLinkeKo)
    If Not LineLinkeKo(k) Is Nothing Then LineLinkeKo(k).Redraw DrawMode
Next k

Exit Sub
err:
    Select Case err
    Case Else
        MsgBox "Error in [clsFenceElement] // Dynamics " & _
        vbCrLf & err.Description, vbCritical, err.Number
'        Resume
    End Select
End Sub

Private Sub CreateLinesRounded(oView As View, Origin As Point3d)
Dim dblSegDist As Double, Delta_Y As Double, i As Long, OriginRound As Point3d, DivPoints() As Point3d, lngDivisionsY As Long, PntsLinkeKo(1) As Point3d

'Linke Linien-Koordinaten
ReDim LineLinkeKo(0) As LineElement
dblSegDist = 1000
OriginRound = Origin
OriginRound.Y = Runden(CDbl(CLng(Origin.Y + 100)), -2)
Delta_Y = Point3dDistance(OriginRound, PtsShapInnen(3))
lngDivisionsY = Int((Delta_Y - 15) / 1000)
If lngDivisionsY > 0 Then
    lngDivisionsY = lngDivisionsY + 1
    ReDim DivPoints(0 To lngDivisionsY - 1) As Point3d: ReDim LineLinkeKo(0)
    DivPoints(0) = PtsShapInnen(0)
    DivPoints(UBound(DivPoints)) = Point3dAddScaled(PtsShapInnen(3), Yv, -15)
    For i = (LBound(DivPoints) + 1) To (UBound(DivPoints))
        If i = 1 Then
            DivPoints(i) = DivPoints(0)
            DivPoints(i).Y = Runden(CDbl(CLng(DivPoints(0).Y + 1100)), -2)
        Else
            DivPoints(i) = Point3dAddScaled(DivPoints(i - 1), Yv, 1000)
        End If
        PntsLinkeKo(0) = DivPoints(i)
        PntsLinkeKo(1) = Point3dAddScaled(DivPoints(i), Xv, 25)
        If Not LineLinkeKo(UBound(LineLinkeKo)) Is Nothing Then ReDim Preserve LineLinkeKo(UBound(LineLinkeKo) + 1)
        Set LineLinkeKo(UBound(LineLinkeKo)) = CreateLineElement2(Nothing, PntsLinkeKo(0), PntsLinkeKo(1))
    Next i
End If
End Sub

Public Function Runden(ByVal Number As Double, ByVal Digits As Integer) As Double
    Runden = Int(Number * 10 ^ Digits + 0.5) / 10 ^ Digits
End Function    


Private Sub IPrimitiveCommandEvents_Keyin(ByVal Keyin As String)
    'not used
End Sub

Private Sub IPrimitiveCommandEvents_Reset()
    CommandState.StopDynamics
    CommandState.StartDefaultCommand
End Sub

Private Sub IPrimitiveCommandEvents_Cleanup()
    nPnts = 0
    CommandState.StopDynamics
End Sub

Private Sub IPrimitiveCommandEvents_Start()
    Set Sh = Nothing
    obAccudrawAn = CommandState.AccuDrawHints.IsEnabled
    If obAccudrawAn = False Then CadInputQueue.SendKeyin "accudraw activate"
End Sub

Hi Jon,

if you see on my Code, you will see that i need a Elements in Inverted View. How can i get a unrotated Cartesian coordinates from Elements of inverted View for case with rotated View. Thanks.

Mikha Zaslavskiy said:

How can i get a unrotated Cartesian coordinates from Elements

In general, elements don't have any rotation.  The exceptions are cell elements, text elements and perhaps some others.  A line or line-string, for example, is a set of coordinates with no intrinsic rotation.  You can rotate the line, which then has a new set of coordinates.

If you have created elements in a no-rotation Cartesian system, then they have no rotation.

You can rotate an element by applying a transform.  Element.Rotate is a shortcut that applies a rotation transform to most elements.

Mikha Zaslavskiy said:

How can i get a unrotated Cartesian coordinates from Elements of inverted View for case with rotated View

I occurs to me that you are not comfortable when discussing geometric algebra.  Here are some reading suggestions that may help.

Jon thank you for your advices. My Problem is in this diskussing, that my dynamic must be beginning with inverted Matrix, becase my Elements as rectangular  and other mus be orthogonal created. If i begin include of my Dynamics my Objects to transform with unrotated Matrix, i dont getting my results. 

I will try get this books, it would be interesting for me i hope. Have a Nice Weekend. With Regards, Mikha