Extending autolisp with Python

[Danielm103]

Lisp functions take a resbuf argument. A resbuf in python is a list of tuples  

Each tuple (Typed value) has a data type and a value, you can also use integers as ARX does

 

Rx.LispType:
    kAngle
    kDottedPair
    kDouble
    kInt16
    kInt32
    kListBegin
    kListEnd
    kNil
    kNone
    kObjectId
    kOrientation
    kPoint2d
    kVector2d
    kPoint3d
    kVector3d
    kT_atom
    kText
    kVoid
    kSelectionSet

 

you can also use integers as ARX does

 

#define RTNONE    5000 /* No result */
#define RTREAL    5001 /*Real number */
#define RTPOINT   5002 /* 2D point X and Y only */
#define RTSHORT   5003 /* Short integer */
#define RTANG     5004 /* Angle */
#define RTSTR     5005 /* String */
#define RTENAME   5006 /* Entity name */
#define RTPICKS   5007 /* Pick set */
#define RTORINT   5008 /* Orientation */
#define RT3DPOINT 5009 /* 3D point - X, Y, and Z */
#define RTLONG    5010 /* Long integer */
#define RTVOID    5014 /* Blank symbol */
#define RTLB      5016 /* list begin */
#define RTLE      5017 /* list end */
#define RTDOTE    5018 /* dotted pair */
#define RTNIL     5019 /* nil */
#define RTT       5021 /* T atom */
#define RTMODELESS 5027 /* interrupted by modeless dialog */

 

[Danielm103]

Create a lisp function by using the “@Ap.LispFunction()”

 

example

from pyrx import Rx, Ge, Gi, Gs, Db, Ap, Ed, Ax
import traceback

@Ap.LispFunction()
def lfunc(resbuf):
    try:
        #iterate the resbuf
        for type, value in resbuf:
            print(type, value)
            
        return resbuf
    except Exception as err:
        traceback.print_exception(err)
        
        

 

[Danielm103]

maybe a useful example, check if two curves overlap

 

the lisp:

(defun c:doit (/ c1 c2)
  (setq c1 (car (entsel "pick curve 1\n")))
  (setq c2 (car (entsel "pick curve 2\n")))
  (check_overlap c1 c2)
)

 

the python

from pyrx import Rx, Ge, Gi, Gs, Db, Ap, Ed, Ax
import traceback


@Ap.LispFunction()
def check_overlap(resbuf):
    try:
        cv1 = None
        cv2 = None

        # check the resbuf
        if len(resbuf) != 2:
            return None

        if resbuf[0][0] != Rx.LispType.kObjectId:
            return None

        if resbuf[1][0] != Rx.LispType.kObjectId:
            return None

        # get the geometry 
        dbc1 = Db.Curve(resbuf[0][1])
        cv1 = dbc1.getAcGeCurve()

        dbc2 = Db.Curve(resbuf[1][1])
        cv2 = dbc2.getAcGeCurve()

        # do the check
        cc = Ge.CurveCurveInt3d(cv1, cv2)
        return cc.overlapCount() > 0

    except Exception as err:
        traceback.print_exception(err)

 

and the results

 

[Danielm103]

some examples of building list to return back to autolisp

 

from pyrx import Rx, Ge, Gi, Gs, Db, Ap, Ed, Ax
import traceback


#return a list
@Ap.LispFunction()
def lfunc1(resbuf):
    try:

        buf = [
            (Rx.LispType.kPoint3d, Ge.Point3d(1, 0, 0)),
            (Rx.LispType.kPoint3d, Ge.Point3d(2, 0, 0)),
            (Rx.LispType.kPoint3d, Ge.Point3d(3, 0, 0)),
            (Rx.LispType.kPoint3d, Ge.Point3d(4, 0, 0)),
        ]
        return buf

    except Exception as err:
        traceback.print_exception(err)


# ((1.0 0.0 0.0) (2.0 0.0 0.0) (3.0 0.0 0.0) (4.0 0.0 0.0))

#return a nested list
@Ap.LispFunction()
def lfunc2(resbuf):
    try:

        buf = [
            
            (Rx.LispType.kListBegin, 0), # these must match
            (Rx.LispType.kPoint3d, Ge.Point3d(1, 0, 0)),
            (Rx.LispType.kPoint3d, Ge.Point3d(2, 0, 0)),
            (Rx.LispType.kListEnd, 0),
            
            (Rx.LispType.kListBegin, 0),
            (Rx.LispType.kPoint3d, Ge.Point3d(3, 0, 0)),
            (Rx.LispType.kPoint3d, Ge.Point3d(4, 0, 0)),
            (Rx.LispType.kListEnd, 0),
            
        ]
        return buf

    except Exception as err:
        traceback.print_exception(err)
        
# (((1.0 0.0 0.0) (2.0 0.0 0.0)) ((3.0 0.0 0.0) (4.0 0.0 0.0)))