vlax-tmatrix (AutoLISP/ActiveX)

Returns a suitable representation for a 4 x 4 transformation matrix to be used in VLA methods

Supported Platforms: Windows only

Signature

(vlax-tmatrix lst)

lst

Type: List

A value of four lists, each containing four numbers, representing transformation matrix elements.

Return Values

Type: Variant

A variant of type safearray, representing the 4×4 transformation matrix.

Examples

Define a transformation matrix and assign its value to variable tmatrix:

(setq tmatrix (vlax-tmatrix '((1 1 1 0) (1 2 3 0) (2 3 4 5) (2 9 8 3))))
#<variant 8197 ...>

Use vlax-safearray->list to view the value of tmatrix in list form:

(vlax-safearray->list (vlax-variant-value tmatrix))
((1.0 1.0 1.0 0.0) (1.0 2.0 3.0 0.0) (2.0 3.0 4.0 5.0) (2.0 9.0 8.0 3.0))

The following code example creates a line and rotates it 90 degrees using a transformation matrix:

(defun Example_TransformBy ( / acadObject acadDocument mSpace lineObj
                               startPt endPt matList transMat) 
  (vl-load-com)      ; Load ActiveX support
  (setq acadObject   (vlax-get-acad-object))
  (setq acadDocument (vla-get-ActiveDocument acadObject))
  (setq mSpace       (vla-get-ModelSpace acadDocument))

;;; Create a line
  (setq startPt (getpoint "Pick the start point"))
  (setq endPt (vlax-3d-point (getpoint startPt "Pick the end point")))
  (setq lineObj (vla-addline mSpace (vlax-3d-point startPt) endPt))

;;; Initialize the transMat variable with a transformation matrix
;;; that will rotate an object by 90 degrees about the point(0,0,0).
;;; Begin by Creating a list of four lists, each containing four
;;; numbers, representing transformation matrix elements.
  (setq matList (list '(0 -1 0 0) '(1 0 0 0) '(0 0 1 0) '(0 0 0 1)))

;;; Use vlax-tmatrix to convert the list to a variant.
  (setq transmat (vlax-tmatrix matlist))

;;;  Transform the line using the defined transformation matrix
  (vla-transformby lineObj transMat)
  (vla-zoomall acadObject)
  (princ "The line is transformed ")
 (princ)
)