AutoCAD Visual LISP / AutoLISP :: Create Materials In 2007 - 2008

In AutoCAD 2006 and previous versions when we had to create a new STANDARD material with a pattern/texture map and attach it to a selection set of objects, first of all we had to load render.arx (arxload “render.arx”) and then we had to call the following function:

;;; matname = New Material Name
;;; ss = Selection Set of Objects
;;; Matfile = The name of the jpg file
(defun SetMaterial (matname ss matfile / r1)
(if (null (member matname (c:rmat "l")))
(if (findfile matfile)

[code]....

The above function checks if a material with name matname exists and if not then it creates a new STANDARD material with name matname, material color (-1.0 -1.0 -1.0), which means derive the color from an object’s ACI (diffuse color), color-weight factor 0 (the amount of diffuse color) and a pattern/texture which is described in the list (list matfile 1.0 1 nil nil nil 1 1). The following table describes the pattern/texture arguments:

matfile name of the bitmap file
1.0 amount of map color to use
1 tile(repeat the patterns)
nil u and v scale factors (AutoCAD used the default values)
nil U and V offsets (AutoCAD used the default values)
nil (reserved by Autodesk)

[code]....

It was not necessary to define CreateNewMaterial with all these arguments, but I do it for future purposes.

In the attached file you can see the definition of MaterialExists, CreateNewMaterial and some other functions:

MaterialExists: Checks if a material exists.

DefaultNewMaterial: Default values for new materials. I have used the AutoCAD defaults, but one can modify them accordingly.

CreateNewMaterial: Creates a new material. If one needs more information on the meaning of the arguments I think Ralph Grabowski’s “Tailoring AutoCAD Rendering” is a good start.

AttachMaterialToEntity:Attaches material to objects

MaterialByLayer: Modifies an object to have material by layer.

AttachMaterialToLayer: Attaches material to a layer.

As you can see I don’t use vlax functions, because I write the code for OEM programming purposes. You can change the functions accordingly.