Returns a suitable representation for a 4 x 4 transformation matrix to be used in VLA methods
Supported Platforms: Windows only
(vlax-tmatrix lst)
Type: List
A value of four lists, each containing four numbers, representing transformation matrix elements.
Type: Variant
A variant of type safearray, representing the 4×4 transformation matrix.
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 "\nPick the start point: "))
(setq endPt (vlax-3d-point (getpoint startPt "\nPick 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)
(prompt "\nThe line has been transformed.")
(princ)
)