topic Re: Transformation Matrix in Inventor Programming Forum

Transformation Matrix

Anonymous — Sun, 22 Sep 2002 23:27:36 GMT

I am trying to figure out how to take the numbers in the Transformation
Matrix which is in an occurrence and use the numbers in it to create a
new transformation matrix.

This is easy enough to do if you can store the matrix itself but I am
trying to store just the four numbers, Length, X, Y and Z then at a
later date, convert these for use in placing a new component in a new
assembly.

pseudo code to get the matrix:
Set .TransMat = IVoccur.Transformation

Will get the transformation, I next write it out to an Excel Spread
Sheet with:

excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Length
excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.X
excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Y
excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Z

Now I want to take the data from the Excel Spread sheet and convert it
back into a Transformation Matrix so I can use it to place a part:

oAsmCompDef.Occurrences.Add("C:\Temp\Part1.ipt", oMatrix)

Where oMatrix is what I want to define from the Spread Sheet data

It would be useful if there was a little more information in help on
this subject. I suppose the other option would be to get all the data
from GetMatrixData and use PutMatrixData

Anyone know how to do this?
CBliss

Re: Transformation Matrix

Anonymous — Mon, 23 Sep 2002 06:53:09 GMT

Charles,

You're assuming a very limited case in the occurrence and you actually only
need three numbers for this. The assumption you're making is that the
occurrence does not have any rotation, it is placed so that the parts
coordinate systems and the assemblies are completely aligned. The only
thing you're defining is the position of the part within the assembly. If
that's all you need then the X, Y, and Z values are enough. If you need to
account for rotation then you could get by with storing an additional six
numbers. (You really need 9, but the other can be derived from these 6.)

The last column of the matrix defines the translation. You can extract the
translation using the following:

excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(1,4)
excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(2,4)
excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(3,4)

To use these numbers later, create a new matrix using the CreateMatrix
method and then using the Cell property of the Matrix object assign the
values you saved back into the matrix. This matrix can then be used to
place a new occurrence or modify an existing one.

The rotation information is stored in columns 1, 2, and 3.

-Brian

"Charles Bliss" wrote in message
news:3D8EC268.2070709@cbliss.com...
> I am trying to figure out how to take the numbers in the Transformation
> Matrix which is in an occurrence and use the numbers in it to create a
> new transformation matrix.
>
> This is easy enough to do if you can store the matrix itself but I am
> trying to store just the four numbers, Length, X, Y and Z then at a
> later date, convert these for use in placing a new component in a new
> assembly.
>
> pseudo code to get the matrix:
> Set .TransMat = IVoccur.Transformation
>
> Will get the transformation, I next write it out to an Excel Spread
> Sheet with:
>
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Length
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.X
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Y
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Z
>
> Now I want to take the data from the Excel Spread sheet and convert it
> back into a Transformation Matrix so I can use it to place a part:
>
> oAsmCompDef.Occurrences.Add("C:\Temp\Part1.ipt", oMatrix)
>
> Where oMatrix is what I want to define from the Spread Sheet data
>
> It would be useful if there was a little more information in help on
> this subject. I suppose the other option would be to get all the data
> from GetMatrixData and use PutMatrixData
>
> Anyone know how to do this?
> CBliss
>

Re:

Anonymous — Mon, 23 Sep 2002 21:32:46 GMT

Still a bit foggy on the concept
Position:
X=.TransMat.Cell(1,4)
Y=.TransMat.Cell(2,4)
Z=.TransMat.Cell(3,4)
So for Rotation, I would need?
aX=.TransMat.Cell(1,1)
bX=.TransMat.Cell(1,2)
cX=.TransMat.Cell(1,3)

aY=.TransMat.Cell(2,1)
bY=.TransMat.Cell(2,2)
cY=.TransMat.Cell(2,3)

aZ=.TransMat.Cell(3,1)
bZ=.TransMat.Cell(3,2)
cZ=.TransMat.Cell(3,3)
Or a total of 12 Numbers?

What would I collect and how would I derive from 6?

What threw me was that there are only Length, X, Y & Z showing in the
Matrix which is shown in the Watch Window. When I use GetMatrixData, it
is an array of 16 numbers. What are the extra 4 for? Is there anything
I can read somewhere which explains this?

Brian Ekins wrote:
> Charles,
>
> You're assuming a very limited case in the occurrence and you actually only
> need three numbers for this. The assumption you're making is that the
> occurrence does not have any rotation, it is placed so that the parts
> coordinate systems and the assemblies are completely aligned. The only
> thing you're defining is the position of the part within the assembly. If
> that's all you need then the X, Y, and Z values are enough. If you need to
> account for rotation then you could get by with storing an additional six
> numbers. (You really need 9, but the other can be derived from these 6.)
>
> The last column of the matrix defines the translation. You can extract the
> translation using the following:
>
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(1,4)
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(2,4)
> excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(3,4)
>
> To use these numbers later, create a new matrix using the CreateMatrix
> method and then using the Cell property of the Matrix object assign the
> values you saved back into the matrix. This matrix can then be used to
> place a new occurrence or modify an existing one.
>
> The rotation information is stored in columns 1, 2, and 3.
>
> -Brian
>
>
> "Charles Bliss" wrote in message
> news:3D8EC268.2070709@cbliss.com...
>
>>I am trying to figure out how to take the numbers in the Transformation
>>Matrix which is in an occurrence and use the numbers in it to create a
>>new transformation matrix.
>>
>>This is easy enough to do if you can store the matrix itself but I am
>>trying to store just the four numbers, Length, X, Y and Z then at a
>>later date, convert these for use in placing a new component in a new
>>assembly.
>>
>>pseudo code to get the matrix:
>>Set .TransMat = IVoccur.Transformation
>>
>>Will get the transformation, I next write it out to an Excel Spread
>>Sheet with:
>>
>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Length
>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.X
>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Y
>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Z
>>
>>Now I want to take the data from the Excel Spread sheet and convert it
>>back into a Transformation Matrix so I can use it to place a part:
>>
>>oAsmCompDef.Occurrences.Add("C:\Temp\Part1.ipt", oMatrix)
>>
>>Where oMatrix is what I want to define from the Spread Sheet data
>>
>>It would be useful if there was a little more information in help on
>>this subject. I suppose the other option would be to get all the data
>>from GetMatrixData and use PutMatrixData
>>
>>Anyone know how to do this?
>>CBliss
>>
>
>
>

Re:

Anonymous — Tue, 24 Sep 2002 00:49:05 GMT

Hi Charles,
Inventor Matrix is not too bad even if not complete as ARX AcGe...

Every time you need a new matrix you need to ask Inventor to provide a new
one:

Public Function NewMatrix()
Set NewMatrix = oApp.TransientGeometry.CreateMatrix
End Function

To access lines and row use Cell method...

Dim oBackSys As Matrix, r As Long, c As Long
Set oBackSys = NewMatrix()
For r = 1 To 4
For c = 1 To 4
oBackSys.Cell(r, c) = oSys.Cell(r, c)
Next
Next

Into the matrix you can store all information about position, rotation, ecc.
I just noticed Autodesk guys tend to use matrices to store data in a compact
way (as array of vectors).

You can find some geom info here
http://www.jtaylor1142001.net/calcjat/CFrames/Index00.htm

Just one thing is a bit tricky... extracting rotation angle from a 3D
matrix. This is an example using quaternions (not really tested onestly!!).

Public Function PI() As Double
PI = Atn(1) * 4
End Function

Public Function Equal(ByVal val1 As Double, ByVal val2 As Double, Optional
ByVal tol As Double = 0.00001)
Equal = Abs(val1 - val2) < tol
End Function

Function Acos(x As Double) As Double
' Inverse Cosine
If Equal(x, 1) Then
Acos = 0
ElseIf Equal(x, -1) Then
Acos = PI()
'Acos = -PI()
Else
Acos = (PI() / 2#) - Atn(x / Sqr(1# - (x * x)))
'Acos = Atn(x / Sqr(-x * x + 1)) + PI() / 2
End If
End Function

Public Function GetMatrixRotationAngle(oMat As Matrix, oAxis As Vector) As
Double

' Be sure the matrix has no scale, mirror or shear...
If Not Equal(oMat.Determinant, 1#) Then
MsgBox "Unable to get piece rotation angle"
GetMatrixRotationAngle = 0#
Exit Function
End If

Dim i As Long
For i = 1 To 3
If Equal(oMat.Cell(i, i), 0#) Then
oMat.Cell(i, i) = 0#
End If
Next

Dim M11 As Double, M22 As Double, M33 As Double
M11 = oMat.Cell(1, 1)
M22 = oMat.Cell(2, 2)
M33 = oMat.Cell(3, 3)

Dim trace As Double
trace = M11 + M22 + M33

Dim s As Double
Dim quat(4) As Double

If trace > 0# Then
s = Sqr(trace + 1#)
quat(0) = s * 0.5
s = 0.5 / s
quat(1) = s * (oMat.Cell(3, 2) - oMat.Cell(2, 3))
quat(2) = s * (oMat.Cell(1, 3) - oMat.Cell(3, 1))
quat(3) = s * (oMat.Cell(2, 1) - oMat.Cell(1, 2))
Else
' find which column has the greater value
Dim j As Long, k As Long
i = 0
If M22 > M11 Then
i = 1
End If
If M33 > oMat.Cell(i + 1, i + 1) Then
i = 2
End If
j = (i + 1) Mod 3
k = (i + 2) Mod 3

s = Sqr(oMat.Cell(i + 1, i + 1) - (oMat.Cell(j + 1, j + 1) +
oMat.Cell(k + 1, k + 1)) + 1#)
quat(i + 1) = s * 0.5
s = 0.5 / s
quat(0) = s * (oMat.Cell(k + 1, j + 1) - oMat.Cell(j + 1, k + 1))
quat(j + 1) = s * (oMat.Cell(j + 1, i + 1) + oMat.Cell(i + 1, j + 1))
quat(k + 1) = s * (oMat.Cell(k + 1, i + 1) + oMat.Cell(i + 1, k + 1))
End If

' Extract the rotation angle
Dim theta As Double
theta = 2# * Acos(quat(0))

If Not Equal(theta, 0#) Then
Dim factor As Double
factor = 1# / Sin(theta * 0.5)

Dim oTmpAxis As Vector
Set oTmpAxis = NewVector(quat(1) * factor, quat(2) * factor, quat(3)
* factor)

'Flip direction if necessary
Dim dotp As Double
dotp = oTmpAxis.DotProduct(oAxis)
If dotp < 0# Then
Call oTmpAxis.ScaleBy(-1#)
theta = PI() * 2# - theta
End If
Else
theta = 0#
End If

GetMatrixRotationAngle = theta

End Function

Hope this helps,

Daniele Piazza
AutoCAD-ME10 Translator Customers Support
QS Informatica

"Charles Bliss" ha scritto nel messaggio
news:3D8FF8FE.9090604@cbliss.com...
> Still a bit foggy on the concept
> Position:
> X=.TransMat.Cell(1,4)
> Y=.TransMat.Cell(2,4)
> Z=.TransMat.Cell(3,4)
> So for Rotation, I would need?
> aX=.TransMat.Cell(1,1)
> bX=.TransMat.Cell(1,2)
> cX=.TransMat.Cell(1,3)
>
> aY=.TransMat.Cell(2,1)
> bY=.TransMat.Cell(2,2)
> cY=.TransMat.Cell(2,3)
>
> aZ=.TransMat.Cell(3,1)
> bZ=.TransMat.Cell(3,2)
> cZ=.TransMat.Cell(3,3)
> Or a total of 12 Numbers?
>
> What would I collect and how would I derive from 6?
>
> What threw me was that there are only Length, X, Y & Z showing in the
> Matrix which is shown in the Watch Window. When I use GetMatrixData, it
> is an array of 16 numbers. What are the extra 4 for? Is there anything
> I can read somewhere which explains this?
>
>
> Brian Ekins wrote:
> > Charles,
> >
> > You're assuming a very limited case in the occurrence and you actually
only
> > need three numbers for this. The assumption you're making is that the
> > occurrence does not have any rotation, it is placed so that the parts
> > coordinate systems and the assemblies are completely aligned. The only
> > thing you're defining is the position of the part within the assembly.
If
> > that's all you need then the X, Y, and Z values are enough. If you need
to
> > account for rotation then you could get by with storing an additional
six
> > numbers. (You really need 9, but the other can be derived from these
6.)
> >
> > The last column of the matrix defines the translation. You can extract
the
> > translation using the following:
> >
> > excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(1,4)
> > excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(2,4)
> > excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(3,4)
> >
> > To use these numbers later, create a new matrix using the CreateMatrix
> > method and then using the Cell property of the Matrix object assign the
> > values you saved back into the matrix. This matrix can then be used to
> > place a new occurrence or modify an existing one.
> >
> > The rotation information is stored in columns 1, 2, and 3.
> >
> > -Brian
> >
> >
> > "Charles Bliss" wrote in message
> > news:3D8EC268.2070709@cbliss.com...
> >
> >>I am trying to figure out how to take the numbers in the Transformation
> >>Matrix which is in an occurrence and use the numbers in it to create a
> >>new transformation matrix.
> >>
> >>This is easy enough to do if you can store the matrix itself but I am
> >>trying to store just the four numbers, Length, X, Y and Z then at a
> >>later date, convert these for use in placing a new component in a new
> >>assembly.
> >>
> >>pseudo code to get the matrix:
> >>Set .TransMat = IVoccur.Transformation
> >>
> >>Will get the transformation, I next write it out to an Excel Spread
> >>Sheet with:
> >>
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Length
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.X
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Y
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Z
> >>
> >>Now I want to take the data from the Excel Spread sheet and convert it
> >>back into a Transformation Matrix so I can use it to place a part:
> >>
> >>oAsmCompDef.Occurrences.Add("C:\Temp\Part1.ipt", oMatrix)
> >>
> >>Where oMatrix is what I want to define from the Spread Sheet data
> >>
> >>It would be useful if there was a little more information in help on
> >>this subject. I suppose the other option would be to get all the data
> >>from GetMatrixData and use PutMatrixData
> >>
> >>Anyone know how to do this?
> >>CBliss
> >>
> >
> >
> >
>

Re:

Anonymous — Tue, 24 Sep 2002 09:28:05 GMT

Charless,
in a 3D world you need the 4X4 transformation matrix to have all the
"movements" in a 3D world:
1. Translation,
2. Rotate X-axis
3. Rotate Y-axis
4. Rotate Z-axis
5. Rotate other axis is a combination of 2..4
6. X scaling
7 Y scaling
8 Z scaling
9 special scaling, i.e. perspective scaling (vanishing point)

I don't know the exact positions of the Cos(X), SIN(X) etc. elements within
the matrix anymore but i wouldn't be supprised if they could be found on the
web. What i can remember is that the last element mat(4,4) is the overall
scaling factor and this should be 1. The last horizontal row is the
perspective row i think but this can also be the last column if the matrix
is in fact the transposed matrix of the 3D 'movement'.
Further more it is important that all the numbers following some rules so
that the inverse matrix can be calculated.

Anton

Re:

Anonymous — Tue, 24 Sep 2002 15:54:07 GMT

Hi Charles,

You can get by with just saving this information.

X = .TransMat.Cell(1,4)
Y = .TransMat.Cell(2,4)
Z = .TransMat.Cell(3,4)

Xx=.TransMat.Cell(1,1)
Xy=.TransMat.Cell(2,1)
Xz=.TransMat.Cell(3,1)

Yx=.TransMat.Cell(1,2)
Yy=.TransMat.Cell(2,2)
Yz=.TransMat.Cell(3,2)

To restore the matrix. Create a new matrix using the CreateMatrix method.
This will create an identity matrix. You can put the values you obtained
previously back in the same location you obtained them. You can derive the
Z vector from the X and Y that you saved. (This only works because your
only defining rotation and translation with the matrix, not scaling or othe
transforms.) The code below does this.

Dim oTG As TransientGeometry
Set oTG = oApp.TransientGeometry

Dim oXVec As Vector
Set oXVec = oTG.CreateVector(Xx, Xy, Xz)

Dim oYVec As Vector
Set oYVec = oTG.CreateVector(Yx, Yy, Yz)

Dim oZVec As Vector
Set oZVec = oXVec.CrossProduct(oYVec)

Zx = oZVec.X
Zy = oZVec.Y
Zz = oZVec.Z

The Z vector goes into the 3 column.

There's a website that has some information on matrices.

http://3dhtml.netzministerium.de/2_basic3dmath.html

-Brian
"Charles Bliss" wrote in message
news:3D8FF8FE.9090604@cbliss.com...
> Still a bit foggy on the concept
> Position:
> X=.TransMat.Cell(1,4)
> Y=.TransMat.Cell(2,4)
> Z=.TransMat.Cell(3,4)
> So for Rotation, I would need?
> aX=.TransMat.Cell(1,1)
> bX=.TransMat.Cell(1,2)
> cX=.TransMat.Cell(1,3)
>
> aY=.TransMat.Cell(2,1)
> bY=.TransMat.Cell(2,2)
> cY=.TransMat.Cell(2,3)
>
> aZ=.TransMat.Cell(3,1)
> bZ=.TransMat.Cell(3,2)
> cZ=.TransMat.Cell(3,3)
> Or a total of 12 Numbers?
>
> What would I collect and how would I derive from 6?
>
> What threw me was that there are only Length, X, Y & Z showing in the
> Matrix which is shown in the Watch Window. When I use GetMatrixData, it
> is an array of 16 numbers. What are the extra 4 for? Is there anything
> I can read somewhere which explains this?
>
>
> Brian Ekins wrote:
> > Charles,
> >
> > You're assuming a very limited case in the occurrence and you actually
only
> > need three numbers for this. The assumption you're making is that the
> > occurrence does not have any rotation, it is placed so that the parts
> > coordinate systems and the assemblies are completely aligned. The only
> > thing you're defining is the position of the part within the assembly.
If
> > that's all you need then the X, Y, and Z values are enough. If you need
to
> > account for rotation then you could get by with storing an additional
six
> > numbers. (You really need 9, but the other can be derived from these
6.)
> >
> > The last column of the matrix defines the translation. You can extract
the
> > translation using the following:
> >
> > excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(1,4)
> > excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(2,4)
> > excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(3,4)
> >
> > To use these numbers later, create a new matrix using the CreateMatrix
> > method and then using the Cell property of the Matrix object assign the
> > values you saved back into the matrix. This matrix can then be used to
> > place a new occurrence or modify an existing one.
> >
> > The rotation information is stored in columns 1, 2, and 3.
> >
> > -Brian
> >
> >
> > "Charles Bliss" wrote in message
> > news:3D8EC268.2070709@cbliss.com...
> >
> >>I am trying to figure out how to take the numbers in the Transformation
> >>Matrix which is in an occurrence and use the numbers in it to create a
> >>new transformation matrix.
> >>
> >>This is easy enough to do if you can store the matrix itself but I am
> >>trying to store just the four numbers, Length, X, Y and Z then at a
> >>later date, convert these for use in placing a new component in a new
> >>assembly.
> >>
> >>pseudo code to get the matrix:
> >>Set .TransMat = IVoccur.Transformation
> >>
> >>Will get the transformation, I next write it out to an Excel Spread
> >>Sheet with:
> >>
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Length
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.X
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Y
> >>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Z
> >>
> >>Now I want to take the data from the Excel Spread sheet and convert it
> >>back into a Transformation Matrix so I can use it to place a part:
> >>
> >>oAsmCompDef.Occurrences.Add("C:\Temp\Part1.ipt", oMatrix)
> >>
> >>Where oMatrix is what I want to define from the Spread Sheet data
> >>
> >>It would be useful if there was a little more information in help on
> >>this subject. I suppose the other option would be to get all the data
> >>from GetMatrixData and use PutMatrixData
> >>
> >>Anyone know how to do this?
> >>CBliss
> >>
> >
> >
> >
>

Re:

Anonymous — Tue, 24 Sep 2002 18:22:51 GMT

Thanks all, it reminds me of things I did in AutoCAD to develop the
correct viewport sizes from solids. I slimmd on this one. I set up an
array of doubles (0 to 15) which I filled using GetMatrixData(dblArray)
I then concatenated it into a string with deliminators and put the
resultant string into an Excel cell. To later place the component, I
parse the string back into an array of doubles and use PutMatrixData to
populate the matrix.

In the process, I discovered that if you put in one wrong number, you
can get some pretty interesting geometry.

Thanks to all for all the really great information. I'm sure it will
come in handy for other things as well.

Brian Ekins wrote:
> Hi Charles,
>
> You can get by with just saving this information.
>
> X = .TransMat.Cell(1,4)
> Y = .TransMat.Cell(2,4)
> Z = .TransMat.Cell(3,4)
>
> Xx=.TransMat.Cell(1,1)
> Xy=.TransMat.Cell(2,1)
> Xz=.TransMat.Cell(3,1)
>
> Yx=.TransMat.Cell(1,2)
> Yy=.TransMat.Cell(2,2)
> Yz=.TransMat.Cell(3,2)
>
> To restore the matrix. Create a new matrix using the CreateMatrix method.
> This will create an identity matrix. You can put the values you obtained
> previously back in the same location you obtained them. You can derive the
> Z vector from the X and Y that you saved. (This only works because your
> only defining rotation and translation with the matrix, not scaling or othe
> transforms.) The code below does this.
>
> Dim oTG As TransientGeometry
> Set oTG = oApp.TransientGeometry
>
> Dim oXVec As Vector
> Set oXVec = oTG.CreateVector(Xx, Xy, Xz)
>
> Dim oYVec As Vector
> Set oYVec = oTG.CreateVector(Yx, Yy, Yz)
>
> Dim oZVec As Vector
> Set oZVec = oXVec.CrossProduct(oYVec)
>
> Zx = oZVec.X
> Zy = oZVec.Y
> Zz = oZVec.Z
>
> The Z vector goes into the 3 column.
>
> There's a website that has some information on matrices.
>
> http://3dhtml.netzministerium.de/2_basic3dmath.html
>
> -Brian
> "Charles Bliss" wrote in message
> news:3D8FF8FE.9090604@cbliss.com...
>
>>Still a bit foggy on the concept
>>Position:
>> X=.TransMat.Cell(1,4)
>> Y=.TransMat.Cell(2,4)
>> Z=.TransMat.Cell(3,4)
>>So for Rotation, I would need?
>> aX=.TransMat.Cell(1,1)
>> bX=.TransMat.Cell(1,2)
>> cX=.TransMat.Cell(1,3)
>>
>> aY=.TransMat.Cell(2,1)
>> bY=.TransMat.Cell(2,2)
>> cY=.TransMat.Cell(2,3)
>>
>> aZ=.TransMat.Cell(3,1)
>> bZ=.TransMat.Cell(3,2)
>> cZ=.TransMat.Cell(3,3)
>>Or a total of 12 Numbers?
>>
>>What would I collect and how would I derive from 6?
>>
>>What threw me was that there are only Length, X, Y & Z showing in the
>>Matrix which is shown in the Watch Window. When I use GetMatrixData, it
>>is an array of 16 numbers. What are the extra 4 for? Is there anything
>>I can read somewhere which explains this?
>>
>>
>>Brian Ekins wrote:
>>
>>>Charles,
>>>
>>>You're assuming a very limited case in the occurrence and you actually
>>
> only
>
>>>need three numbers for this. The assumption you're making is that the
>>>occurrence does not have any rotation, it is placed so that the parts
>>>coordinate systems and the assemblies are completely aligned. The only
>>>thing you're defining is the position of the part within the assembly.
>>
> If
>
>>>that's all you need then the X, Y, and Z values are enough. If you need
>>
> to
>
>>>account for rotation then you could get by with storing an additional
>>
> six
>
>>>numbers. (You really need 9, but the other can be derived from these
>>
> 6.)
>
>>>The last column of the matrix defines the translation. You can extract
>>
> the
>
>>>translation using the following:
>>>
>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(1,4)
>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(2,4)
>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Cell(3,4)
>>>
>>>To use these numbers later, create a new matrix using the CreateMatrix
>>>method and then using the Cell property of the Matrix object assign the
>>>values you saved back into the matrix. This matrix can then be used to
>>>place a new occurrence or modify an existing one.
>>>
>>>The rotation information is stored in columns 1, 2, and 3.
>>>
>>>-Brian
>>>
>>>
>>>"Charles Bliss" wrote in message
>>>news:3D8EC268.2070709@cbliss.com...
>>>
>>>
>>>>I am trying to figure out how to take the numbers in the Transformation
>>>>Matrix which is in an occurrence and use the numbers in it to create a
>>>>new transformation matrix.
>>>>
>>>>This is easy enough to do if you can store the matrix itself but I am
>>>>trying to store just the four numbers, Length, X, Y and Z then at a
>>>>later date, convert these for use in placing a new component in a new
>>>>assembly.
>>>>
>>>>pseudo code to get the matrix:
>>>>Set .TransMat = IVoccur.Transformation
>>>>
>>>>Will get the transformation, I next write it out to an Excel Spread
>>>>Sheet with:
>>>>
>>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Length
>>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.X
>>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Y
>>>>excelSheet.Cells(rownum, colnum).Value = .TransMat.Translation.Z
>>>>
>>>>Now I want to take the data from the Excel Spread sheet and convert it
>>>>back into a Transformation Matrix so I can use it to place a part:
>>>>
>>>>oAsmCompDef.Occurrences.Add("C:\Temp\Part1.ipt", oMatrix)
>>>>
>>>>Where oMatrix is what I want to define from the Spread Sheet data
>>>>
>>>>It would be useful if there was a little more information in help on
>>>>this subject. I suppose the other option would be to get all the data
>>>
>>>>from GetMatrixData and use PutMatrixData
>>>
>>>>Anyone know how to do this?
>>>>CBliss
>>>>
>>>
>>>
>>>
>
>

Re:

Anonymous — Wed, 25 Sep 2002 09:46:12 GMT

>In the process, I discovered that if you put in one wrong number, you
>can get some pretty interesting geometry.

He, Charles found new purposes for Inventor: ART.

Re:

Anonymous — Wed, 25 Sep 2002 17:53:02 GMT

Go ahead, place a part in an assembly using a messed up matrix.

Anton van Buiten wrote:
>>In the process, I discovered that if you put in one wrong number, you
>>can get some pretty interesting geometry.
>
>
> He, Charles found new purposes for Inventor: ART.
>
>
>
>