eCannotScaleNonUniformly when using transformBy

[gswifort]

I'm having trouble transforming a block. My main goal is to transform a polyline. I know I can't scale it nonuniformly directly. However, I once used a workaround by adding the polyline to the block first, then scaling it, and then exploding the block. This approach works if I simply scale the block. However, if I try to use .transformBy(), I get eCannotScaleNonUniformly.

@command
def doit2():
    pline = Db.Polyline([Ge.Point3d(0, 0, 0), Ge.Point3d(10, 0, 0), Ge.Point3d(10, 10, 0)])
    SX = 5.0
    SY = -3.0
    SZ = 1.0
    matrix = Ge.Matrix3d.fromCollection(
        [
            [SX, 0, 0, 0],
            [0, SY, 0, 0],
            [0, 0, SZ, 0],
            [0, 0, 0, 1],
        ]
    )
    try:
        pline.transformBy(matrix)
    except Db.ErrorStatusException as err:
        assert err.code == Db.ErrorStatus.eCannotScaleNonUniformly
    pline2 = Db.Polyline.cloneFrom(pline)
    bt = Db.BlockTable(Db.curDb().blockTableId(), Db.OpenMode.kForWrite)
    btr_1 = Db.BlockTableRecord()
    btr_1.appendAcDbEntity(pline)
    btr_1_id = bt.add(btr_1)
    bref_1 = Db.BlockReference(Ge.Point3d(0, 0, 0), btr_1_id)
    try:
        bref_1.transformBy(matrix)
    except Db.ErrorStatusException as err:
        assert err.code == Db.ErrorStatus.eCannotScaleNonUniformly  # !!!
    btr_2 = Db.BlockTableRecord()
    btr_2.appendAcDbEntity(pline2)
    btr_2_id = bt.add(btr_2)
    bref_2 = Db.BlockReference(Ge.Point3d(0, 0, 0), btr_2_id)
    bref_2.setScaleFactors(Ge.Scale3d(SX, SY, SZ))
    bref_1_id = Db.curDb().addToModelspace(bref_1)
    print(f"Added BlockReference 1 with handle: {bref_1_id.handle()}")
    bref_2_id = Db.curDb().addToModelspace(bref_2)
    print(f"Added BlockReference 2 with handle: {bref_2_id.handle()}")

[CEXT-Dan]

Yeah, TransformBy will throw. The work around is to add it to a block, scale the reference, then explode it.

Or you can transform the vertices

        pnts =  Ge.Point3dArray()
        pnts.extend([Ge.Point3d(0, 0, 0), Ge.Point3d(10, 0, 0), Ge.Point3d(10, 10, 0)])

        SX = 5.0
        SY = -3.0
        SZ = 1.0

        matrix = Ge.Matrix3d()
        matrix.setCoordSystem(
            Ge.Point3d.kOrigin,
            Ge.Vector3d.kXAxis * SX,
            Ge.Vector3d.kYAxis * SY,
            Ge.Vector3d.kZAxis * SZ,
        )
        
        pline = Db.Polyline(pnts)
        Db.curDb().addToModelspace(pline)
        
        clonepnts = Ge.Point3dArray()
        clonepnts.extend(pline.toPoint3dList())
        clonepnts.transformBy(matrix)
        clone = Db.Polyline(clonepnts)
        Db.curDb().addToModelspace(clone)