Remove .open() call from the .render() method

Having this call there was necessary in the past as the open() method would
need the canvas size as a parameter. This is now determined automatically
after rendering.

Still calling open() is deprecated but won't result in an error.

boxes/__init__.py

@@ -219,6 +219,7 @@ class Boxes:
 
     def __init__(self):
         self.formats = formats.Formats()
+        self.ctx = None
         description = self.__doc__
         if self.description:
             description += "\n\n" + self.description
@@ -277,6 +278,8 @@ class Boxes:
 
         Call this function from your .render() method
         """
+        if self.ctx is not None:
+            return
 
         self.bedBoltSettings = (3, 5.5, 2, 20, 15)  # d, d_nut, h_nut, l, l1
         self.hexHolesSettings = (5, 3, 'circle')  # r, dist, style

boxes/generators/_template.py

@@ -47,8 +47,6 @@ class BOX(Boxes): # Change class name!
         # adjust to the variables you want in the local scope
         x, y, h = self.x, self.y, self.h
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         # Create new Edges here if needed E.g.:
         s = edges.FingerJointSettings(self.thickness, relative=False,

boxes/generators/alledges.py

@@ -36,8 +36,6 @@ class AllEdges(Boxes):
     def render(self):
         x = self.x
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         chars = list(self.edges.keys())
         chars.sort(key=lambda c: c.lower() + (c if c.isupper() else ''))

boxes/generators/angledbox.py

@@ -72,7 +72,6 @@ class AngledBox(Boxes):
         self.move(tx, ty, move)
 
     def render(self):
-        self.open()
 
         x, y, h, n = self.x, self.y, self.h, self.n
 

boxes/generators/angledcutjig.py

@@ -44,8 +44,6 @@ class AngledCutJig(Boxes): # Change class name!
         # adjust to the variables you want in the local scope
         x, y = self.x, self.y
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         th = x * math.tan(math.radians(90-self.angle))
         l = (x**2 + th**2)**0.5

boxes/generators/arcade.py

@@ -76,8 +76,6 @@ class Arcade(Boxes):
         self.top = 100-t
         self.topback = 200-0.5*t
 
-        # Initialize canvas
-        self.open()
         # Floor
         self.rectangularWall(width, self.bottom, "efff", move="up")
         # Back

boxes/generators/bintray.py

@@ -106,7 +106,6 @@ class BinTray(Boxes):
         hi = self.hi = h
         t = self.thickness
 
-        self.open()
 
         self.addPart(BinFrontEdge(self, self))
         self.addPart(BinFrontSideEdge(self, self))

boxes/generators/cardbox.py

@@ -96,7 +96,6 @@ class CardBox(Boxes):
             self.fingerHolesAt(0.5*t + (c+t)*i, 0, y, 90)
 
     def render(self):
-        self.open()
         h = self.h
         t = self.thickness
 

boxes/generators/castle.py

@@ -27,7 +27,6 @@ class Castle(Boxes):
         self.addSettingsArgs(edges.FingerJointSettings)
 
     def render(self, t_x=70, t_h=250, w1_x=300, w1_h=120, w2_x=100, w2_h=120):
-        self.open()
         s = edges.FingerJointSettings(10.0, relative=True,
                                       space=1, finger=1,
                                       width=self.thickness)

boxes/generators/closedbox.py

@@ -28,7 +28,6 @@ class ClosedBox(Boxes):
         self.buildArgParser("x", "y", "h", "outside")
 
     def render(self):
-        self.open()
 
         x, y, h = self.x, self.y, self.h
 

boxes/generators/concaveknob.py

@@ -49,8 +49,6 @@ class ConcaveKnob(Boxes):
 
     def render(self):
         t = self.thickness
-        # Initialize canvas
-        self.open()
         self.parts.concaveKnob(self.diameter, self.serrations,
                                self.rounded, self.angle,
                                callback=lambda:self.dHole(0, 0,

boxes/generators/display.py

@@ -40,8 +40,6 @@ class Display(Boxes):
         x, h, r = self.x, self.h, self.radius
         a = self.angle
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         self.roundedPlate(0.7*x, x, r, "e", move="up")
 

boxes/generators/displaycase.py

@@ -36,7 +36,6 @@ class DisplayCase(Boxes):
         )
 
     def render(self):
-        self.open()
 
         x, y, h = self.x, self.y, self.h
 

boxes/generators/displayshelf.py

@@ -61,8 +61,6 @@ class DisplayShelf(Boxes): # change class name here and below
         if self.outside:
             x = self.adjustSize(x)
         
-        # Initialize canvas
-        self.open()
 
         a = math.radians(self.angle)
 

boxes/generators/drillbox.py

@@ -54,7 +54,6 @@ in 0.5mm steps, 3 holes each size"""
         x, y, h = self.x, self.y, self.h
         t = self.thickness
 
-        self.open()
         self.edges["f"].settings.setValues(self.thickness, space=3, finger=3, surroundingspaces=1)
 
         self.rectangularWall(x, h, "FfeF", callback=[self.holesx], move="right")

boxes/generators/electronicsbox.py

@@ -56,7 +56,6 @@ class ElectronicsBox(Boxes):
         self.fingerHolesAt(self.y, self.h-1.5*t, self.triangle, 180)
         
     def render(self):
-        self.open()
 
         t = self.thickness
         self.h = h = self.h + 2*t # compensate for lid

boxes/generators/flexbox.py

@@ -116,7 +116,6 @@ class FlexBox(boxes.Boxes):
         r = min(r, x / 2.0)
         self.radius = r = min(r, max(0, (y - self.latchsize) / 2.0))
 
-        self.open()
 
         self.surroundingWall(move="up")
         self.flexBoxSide(self.x, self.y, self.radius, move="right")

boxes/generators/flexbox2.py

@@ -105,7 +105,6 @@ class FlexBox2(Boxes):
         self.radius = min(self.radius, max(0, self.h - self.latchsize))
         self.c4 = c4 = math.pi * self.radius * 0.5
 
-        self.open()
 
         self.moveTo(2 * self.thickness, self.thickness)
 

boxes/generators/flexbox3.py

@@ -146,7 +146,6 @@ class FlexBox3(Boxes):
         width = 2 * x + y - 2 * r + c4 + 14 * thickness + 3 * h  # lock
         height = y + z + 8 * thickness
 
-        self.open()
 
         s = edges.FingerJointSettings(self.thickness, finger=1.,
                                       space=1., surroundingspaces=1)

boxes/generators/flexbox4.py

@@ -110,7 +110,6 @@ class FlexBox4(Boxes):
         self.radius = min(self.radius, max(0, self.y - self.latchsize))
         self.c4 = c4 = math.pi * self.radius * 0.5
 
-        self.open()
 
         self.surroundingWall(move="up")
         self.flexBoxSide(self.x, self.y, self.radius, move="right")

boxes/generators/flextest.py

@@ -29,7 +29,6 @@ class FlexTest(Boxes):
 
     def render(self):
         x, y = self.x, self.y
-        self.open()
 
         self.moveTo(5, 5)
         self.edge(10)

boxes/generators/flextest2.py

@@ -32,7 +32,6 @@ class FlexTest2(Boxes):
     def render(self):
         x, y = self.x, self.y
 
-        self.open()
         self.rectangularWall(x, y, callback=[lambda: self.flex2D(x, y, self.fw)])
 
 

boxes/generators/folder.py

@@ -33,7 +33,6 @@ class Folder(Boxes):
     def render(self):
         x, y, r, h = self.x, self.y, self.r, self.h
         c2 = math.pi * h
-        self.open()
         self.moveTo(r + self.thickness, self.thickness)
         self.edge(x - r)
         self.edges["X"](c2, y)

boxes/generators/gear.py

@@ -56,8 +56,6 @@ class Gears(Boxes):
     def render(self):
         # adjust to the variables you want in the local scope
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         if not self.shaft2:
             self.shaft2 = self.shaft1

boxes/generators/gearbox.py

@@ -42,8 +42,6 @@ class GearBox(Boxes):
             help="number of stages in the gear reduction")
 
     def render(self):
-        # Initialize canvas
-        self.open()
 
         if self.teeth2 < self.teeth1:
             self.teeth2, self.teeth1 = self.teeth1, self.teeth2

boxes/generators/hingebox.py

@@ -34,7 +34,6 @@ class HingeBox(Boxes):
             help="split the lid in y direction (mm)")
 
     def render(self):
-        self.open()
 
         x, y, h, hl = self.x, self.y, self.h, self.lidheight
         s = self.splitlid

boxes/generators/hooks.py

@@ -43,7 +43,6 @@ class Hook(Boxes):
             help="angle of the support underneeth")
 
     def render(self):
-        self.open()
 
         self.angle = min(self.angle, 80)
         t = self.thickness

boxes/generators/integratedhingebox.py

@@ -33,7 +33,6 @@ class IntegratedHingeBox(Boxes):
         
 
     def render(self):
-        self.open()
 
         x, y, h, hl = self.x, self.y, self.h, self.lidheight
 

boxes/generators/jigsaw.py

@@ -80,8 +80,6 @@ class JigsawPuzzle(Boxes):  # change class name here and below
     def render(self):
         size = self.size
         t = self.thickness
-        # Initialize canvas
-        self.open()
         self.burn = 0.0
         self.moveTo(10, 10)
         self.hilbert(self.depth)

boxes/generators/lamp.py

@@ -90,7 +90,6 @@ class Lamp(Boxes):
         h : height box
         """
 
-        self.open()
 
         # self.edges["f"].settings = (5, 5) # XXX
 

boxes/generators/laserclamp.py

@@ -85,7 +85,6 @@ parts sliding on each other to reduce friction.
     def render(self):
         t = self. thickness
         h_max, h_min, h_extra = self.maxheight, self.minheight,self.extraheight
-        self.open()
 
         if h_extra and h_extra < 2*t:
             h_extra = 2*t

boxes/generators/lbeam.py

@@ -35,7 +35,6 @@ class LBeam(Boxes):
             y = self.adjustSize(y, False)
 
 
-        self.open()
 
         self.rectangularWall(x, h, "eFee", move="right")
         self.rectangularWall(y, h, "eeef")

boxes/generators/magazinefile.py

@@ -69,7 +69,6 @@ class MagazinFile(Boxes):
         self.hi = hi = self.hi or (h / 2.0)
         t = self.thickness
 
-        self.open()
 
         with self.saved_context():
             self.rectangularWall(x, h, "Ffef", move="up")

boxes/generators/nemamount.py

@@ -36,7 +36,6 @@ class NemaMount(Boxes):
 
         x = y = h = motor + 2*t
 
-        self.open()
 
         self.rectangularWall(x, y, "ffef", callback=[
             lambda: self.NEMA(self.size, x/2, y/2)], move="right")

boxes/generators/openbox.py

@@ -35,7 +35,6 @@ class OpenBox(Boxes):
             y = self.adjustSize(y, False)
             h = self.adjustSize(h, False)
 
-        self.open()
 
         d2 = [edges.Bolts(2)]
         d3 = [edges.Bolts(3)]

boxes/generators/organpipe.py

@@ -126,8 +126,6 @@ class OrganPipe(Boxes): # Change class name!
 
         total_length = resonator_length + base_length
         
-        # Initialize canvas
-        self.open()
 
         e = ["f", "e",
              edges.CompoundEdge(self, "fef", (resonator_length - mouth_height - 10*t, mouth_height + 10*t, base_length)), "f"]

boxes/generators/ottobody.py

@@ -98,7 +98,6 @@ class OttoBody(Boxes):
         self.move(w+4, h+8+t, move)
 
     def render(self):
-        self.open()
 
         self.x = x = 60.
         self.y = y = 60.

boxes/generators/ottolegs.py

@@ -104,8 +104,6 @@ class OttoLegs(Boxes):
     def render(self):
         # adjust to the variables you want in the local scope
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         ws = 25
         lx, ly, lh = 12.4, 23.5, max(self.length, ws+6+t)

boxes/generators/ottosoles.py

@@ -45,8 +45,6 @@ class OttoSoles(Boxes):
         w2 = w * 2**0.5 - c2 / 2
         d = w * math.tan(math.radians(22.5))
 
-        # Initialize canvas
-        self.open()
         
         self.edges["d"].settings.setValues(w, size=0.4, depth=0.3,
                                            radius=0.05)

boxes/generators/paintbox.py

@@ -68,8 +68,6 @@ class PaintStorage(Boxes):
         x, y = self.x, self.y
         t = self.thickness
         
-        # Initialize canvas
-        self.open()
 
         stack = self.edges['s'].settings
         h = self.canheight - stack.height - stack.holedistance + t

boxes/generators/planetary.py

@@ -49,8 +49,6 @@ class Planetary(Boxes):
         #    help="number of stages in the gear reduction")
 
     def render(self):
-        # Initialize canvas
-        self.open()
 
         ringteeth = self.sunteeth + 2 * self.planetteeth
         spoke_width = 3 * self.shaft

boxes/generators/planetary2.py

@@ -77,8 +77,6 @@ class Planetary2(Boxes):
 
 
     def render(self):
-        # Initialize canvas
-        self.open()
 
         ringteeth = self.sunteeth + 2 * self.planetteeth
         t = self.thickness

boxes/generators/polehook.py

@@ -99,8 +99,6 @@ class PoleHook(Boxes): # change class name here and below
         # adjust to the variables you want in the local scope
         d = self.diameter
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         shh = self.screwheadheight
         self.bedBoltSettings = (self.screw, self.screwhead, shh, d/4+shh, d/4)  # d, d_nut, h_nut, l, l

boxes/generators/pulley.py

@@ -69,8 +69,6 @@ class Pulley(Boxes):
     def render(self):
         # adjust to the variables you want in the local scope
         t = self.thickness
-        # Initialize canvas
-        self.open()
 
         if self.top:
             self.disk(

boxes/generators/rack19box.py

@@ -63,7 +63,6 @@ class Rack19Box(Boxes):
         
         
     def _render(self, type):
-        self.open()
 
         t = self.thickness
         self.h = h = self.height * 44.45 - 0.787 - t

boxes/generators/rackbox.py

@@ -64,7 +64,6 @@ class RackBox(Boxes):
         
         
     def render(self):
-        self.open()
 
         t = self.thickness
         self.h = h = self.h + 2*t # compensate for lid

boxes/generators/rectangularWall.py

@@ -62,8 +62,6 @@ class RectangularWall(Boxes):
 
     def render(self):
         # adjust to the variables you want in the local scope
-        # Initialize canvas
-        self.open()
         t = self.thickness
 
         self.edgetypes = [self.bottom_edge, self.right_edge, self.top_edge, self.left_edge]

boxes/generators/regularbox.py

@@ -38,7 +38,6 @@ class RegularBox(Boxes):
             help="style of the top and lid")
 
     def render(self):
-        self.open()
 
         r, h, n = self.radius, self.h, self.n
 

boxes/generators/robotarm.py

@@ -44,8 +44,6 @@ class RobotArm(Boxes): # change class name here and below
                 help="length of segment axle to axle")
 
     def render(self):
-        # Initialize canvas
-        self.open()
 
         for i in range(5, 0,-1):
             armtype = getattr(self, "type%i" % i)

boxes/generators/rotary.py

@@ -189,8 +189,6 @@ class Rotary(Boxes):
         a = self.a = self.axle
         bw, bh = self.beamwidth, self.beamheight
 
-        # Initialize canvas
-        self.open()
         # self.spacing = 0.1 * t
 
         # Change settings of default edges if needed. E.g.:

boxes/generators/roundedbox.py

@@ -58,7 +58,6 @@ class RoundedBox(Boxes):
             self.corner(90, r)
 
     def render(self):
-        self.open()
 
         x, y, h, r = self.x, self.y, self.h, self.radius
 

boxes/generators/royalgame.py

@@ -163,8 +163,6 @@ class RoyalGame(Boxes): # Change class name!
         self.size = size = x / 8.0
         h = size/2 * 3**0.5
         y = 3 * size
-        # Initialize canvas
-        self.open()
 
         self.rectangularWall(x, h, "FLFF", move="right")
         self.rectangularWall(y, h, "nlmE", callback=[

boxes/generators/shutterbox.py

@@ -159,8 +159,6 @@ class ShutterBox(Boxes):
         self.radius = r = min(r, h/2)
 
         t = self.thickness
-        # Initialize canvas
-        self.open()
         self.ctx.save()
         self.side(x, h, r, style, move="right")
         self.side(x, h, r, style, move="right")

boxes/generators/silverwarebox.py

@@ -91,7 +91,6 @@ class Silverware(Boxes):
         h = self.h
         r = self.cornerradius
 
-        self.open()
         t = self.thickness
         b = self.burn
 

boxes/generators/stachel.py

@@ -86,8 +86,6 @@ class Stachel(Boxes):
         
 
     def render(self):
-        # Initialize canvas
-        self.open()
 
         ri = self.flutediameter / 2.0
         ro = ri + self.wall

boxes/generators/trafficlight.py

@@ -122,8 +122,6 @@ When turned by 90°, it can be also used to create a bottle holder."""
 
         th = n * (h + t) - t
         
-        # Initialize canvas
-        self.open()
 
         self.addPart(ShadyEdge(self, None))
 

boxes/generators/trayinsert.py

@@ -37,7 +37,6 @@ class TrayInsert(Boxes):
         h = self.h
         t = self.thickness
 
-        self.open()
 
         # Inner walls
         for i in range(len(self.sx) - 1):

boxes/generators/traylayout.py

@@ -151,7 +151,6 @@ class TrayLayout2(TrayLayout):
             for f in line:
                 hasfloor |= f
 
-        self.open()
 
         self.edges["s"] = boxes.edges.Slot(self, self.hi / 2.0)
         self.edges["C"] = boxes.edges.CrossingFingerHoleEdge(self, self.hi)

boxes/generators/two_piece.py

@@ -44,8 +44,6 @@ class TwoPiece(Boxes):
             y -= 4*t + 2*p
             h -= 2 * t
 
-        # Initialize canvas
-        self.open()
 
         # Adjust h edge with play
         self.edges["f"].settings.setValues(t, False, edge_width=self.edges["f"].settings.edge_width + p)

boxes/generators/typetray.py

@@ -88,7 +88,6 @@ class TypeTray(_TopEdge):
         hi = self.hi = self.hi or h
         t = self.thickness
 
-        self.open()
 
         # outer walls
         b = self.bottom_edge

boxes/generators/ubox.py

@@ -93,7 +93,6 @@ class UBox(_TopEdge, _ChestLid):
 
         self.radius = r = min(r, x/2.0, y)
 
-        self.open()
 
         t1, t2, t3, t4 = self.topEdges(self.top_edge)
 

boxes/generators/unevenheightbox.py

@@ -69,7 +69,6 @@ class UnevenHeightBox(Boxes):
 
 
     def render(self):
-        self.open()
 
         x, y = self.x, self.y
         heights = [self.height0, self.height1, self.height2, self.height3]

boxes/generators/universalbox.py

@@ -56,7 +56,6 @@ class UniversalBox(_TopEdge, _ChestLid):
         x, y, h = self.x, self.y, self.h
         t = self.thickness
 
-        self.open()
 
         t1, t2, t3, t4 = self.topEdges(self.top_edge)
         b = self.edges.get(self.bottom_edge, self.edges["F"])

boxes/generators/waivyknob.py

@@ -46,8 +46,6 @@ class WaivyKnob(Boxes):
 
     def render(self):
         t = self.thickness
-        # Initialize canvas
-        self.open()
         angle = self.serrationangle
         self.parts.waivyKnob(self.diameter, self.serrations, angle,
                              callback=lambda:self.dHole(0, 0, d=self.bolthole,

boxes/generators/winerack.py

@@ -110,7 +110,6 @@ class WineRack(Boxes):
         self.cy = cy = int((y-dy-t) // (r+dy))
         self.delta = 3**0.5/6.*t
 
-        self.open()
         self.rectangularWall(x, y, callback=[self.wallCB], move="up")
         self.rectangularWall(x, y, callback=[lambda:self.wallCB(backwall=True)], move="up")
         self.rectangularWall(x, y, callback=[lambda:self.wallCB(frontwall=True)], move="up")

scripts/boxes

@@ -68,6 +68,7 @@ def run_generator(name, args):
     if lower_name in generators.keys():
         box = generators[lower_name]()
         box.parseArgs(args)
+        box.open()
         box.render()
         box.close()
     else:

scripts/boxes_example.ipynb

@@ -27,7 +27,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 6,
+   "execution_count": 5,
    "metadata": {
     "scrolled": true
    },
@@ -36,7 +36,7 @@
      "data": {
       "image/svg+xml": [
        "<svg height=\"210mm\" version=\"1.1\" viewBox=\"0 9790 170 210\" width=\"170mm\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\n",
-       "<g id=\"surface4\">\n",
+       "<g id=\"surface11\">\n",
        "<path d=\"M 150 50.103125 L 0 50.103125 M 0 50.103125 L -3 50.103125 C -3.054688 50.103125 -3.101562 50.060156 -3.101562 50.001562 M -3.101562 50.001562 L -3.101562 50.001562 M -3.101562 50.001562 L -3.101562 37.001562 M -3.101562 37.001562 C -3.101562 36.946875 -3.058594 36.9 -3 36.9 M -3 36.9 L 0 36.9 C -0.0546875 36.9 -0.101562 36.942969 -0.101562 37.001562 M -0.101562 37.001562 L -0.101562 28.001562 C -0.101562 28.05625 -0.0585938 28.103125 0 28.103125 M 0 28.103125 L -3 28.103125 C -3.054688 28.103125 -3.101562 28.060156 -3.101562 28.001562 M -3.101562 28.001562 L -3.101562 22.001562 M -3.101562 22.001562 C -3.101562 21.946875 -3.058594 21.9 -3 21.9 M -3 21.9 L 0 21.9 C -0.0546875 21.9 -0.101562 21.942969 -0.101562 22.001562 M -0.101562 22.001562 L -0.101562 13.001562 C -0.101562 13.05625 -0.0585938 13.103125 0 13.103125 M 0 13.103125 L -3 13.103125 C -3.054688 13.103125 -3.101562 13.060156 -3.101562 13.001562 M -3.101562 13.001562 L -3.101562 0.0015625 M -3.101562 0.0015625 L -3.101562 -5.998438 C -3.101562 -6.053125 -3.058594 -6.1 -3 -6.1 M -3 -6.1 L 0 -6.1 M 0 0.0015625 \" style=\"fill:none;stroke-width:0.2;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(0%,0%,0%);stroke-opacity:1;stroke-miterlimit:10;\" transform=\"matrix(-1,-0.000000000000000122,-0.000000000000000122,1,153.851562,9949.045313)\"/>\n",
        "<path d=\"M 0 -0.000000000000028422 C 1.867188 -0.000000000000028422 1.867188 -2.796875 0 -2.796875 C -1.863281 -2.796875 -1.863281 -0.000000000000028422 0 -0.000000000000028422 \" style=\"fill:none;stroke-width:0.2;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(0%,0%,100%);stroke-opacity:1;stroke-miterlimit:10;\" transform=\"matrix(-0.000000000000000184,-1,-1,0.000000000000000184,142.453125,9959.046875)\"/>\n",
        "<path d=\"M 0 0 C -0.0546875 0 -0.101562 0.046875 -0.101562 0.101562 M -0.101562 0.101562 L -0.101562 -2.898438 C -0.101562 -2.84375 -0.0585938 -2.796875 0 -2.796875 M 0 -2.796875 L -9 -2.796875 C -8.945312 -2.796875 -8.898438 -2.839844 -8.898438 -2.898438 M -8.898438 -2.898438 L -8.898438 0.101562 C -8.898438 0.046875 -8.941406 0 -9 0 M -9 0 L 0 0 \" style=\"fill:none;stroke-width:0.2;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(0%,0%,100%);stroke-opacity:1;stroke-miterlimit:10;\" transform=\"matrix(1,-0,-0,-1,143.351562,9946.046875)\"/>\n",
@@ -96,7 +96,6 @@
     "    def render(self):\n",
     "        x, y, h = self.x, self.y, self.h\n",
     "        t = self.thickness\n",
-    "        self.open()\n",
     "        \n",
     "        # render-magic goes here\n",
     "        \n",
@@ -113,6 +112,7 @@
     "b = Example()\n",
     "fd, fn = tempfile.mkstemp()\n",
     "b.parseArgs(['--reference=0', '--debug=0', '--output=' + fn])\n",
+    "b.open()\n",
     "b.render()\n",
     "b.close()\n",
     "\n",

scripts/boxesserver

@@ -395,6 +395,7 @@ Create boxes and more with a laser cutter!
                                box.format,
                                [('Content-type', 'application/unknown; charset=utf-8')]))
             fd, box.output = tempfile.mkstemp()
+            box.open()
             box.render()
             box.close()
             result = open(box.output).readlines()