New Edge type to clip on sides

Still untested due to lackof laser cutter

boxes/__init__.py

@@ -235,7 +235,7 @@ class Boxes:
             elif arg == "top_edge":
                 self.argparser.add_argument(
                     "--top_edge",  action="store",
-                    type=ArgparseEdgeType("eES"), choices=list("eES"),
+                    type=ArgparseEdgeType("ecES"), choices=list("ecES"),
                     default="e", help="edge type for top edge")
             else:
                 raise ValueError("No default for argument", arg)
@@ -272,6 +272,7 @@ class Boxes:
         self.addPart(edges.Edge(self, None))
         self.addPart(edges.OutSetEdge(self, None))
 
+        # Finger joints
         # Share settings object
         s = edges.FingerJointSettings(self.thickness)
         s.setValues(self.thickness,
@@ -282,17 +283,22 @@ class Boxes:
         self.addPart(edges.FingerJointEdgeCounterPart(self, s))
         self.addPart(edges.FingerHoles(self, s), name="fingerHolesAt")
         self.addPart(edges.FingerHoleEdge(self, None))
-
+        # Stackable
         ss = edges.StackableSettings(self.thickness)
         self.addPart(edges.StackableEdge(self, ss, s))
         self.addPart(edges.StackableEdgeTop(self, ss, s))
-
+        # Dove tail joints
         s = edges.DoveTailSettings(self.thickness)
         self.addPart(edges.DoveTailJoint(self, s))
         self.addPart(edges.DoveTailJointCounterPart(self, s))
+        # Flex
         s = edges.FlexSettings(self.thickness)
         self.addPart(edges.FlexEdge(self, s))
-
+        # Clickable
+        s = edges.ClickSettings(self.thickness)
+        self.addPart(edges.ClickConnector(self, s))
+        self.addPart(edges.ClickEdge(self, s))
+        # Nuts
         self.addPart(NutHole(self, None))
 
     def _init_surface(self, width, height):

boxes/edges.py

@@ -550,6 +550,129 @@ class StackableEdgeTop(StackableEdge):
     description = "Stackable (top)"
     bottom = False
 
+#############################################################################
+####     Click Joints
+#############################################################################
+
+class ClickSettings(Settings):
+    absolute_params = {
+        "angle" : 5,
+        }
+
+    relative_params = {
+        "depth" : 3.0,
+        "bottom_radius" : 0.1,
+        }
+
+class ClickConnector(BaseEdge):
+    char = "c"
+    description = "Click on (bottom side)"
+
+    def hook(self, reverse=False):
+        t = self.thickness
+        a = self.settings.angle
+        d = self.settings.depth
+        r = self.settings.bottom_radius
+        c = math.cos(math.radians(a))
+        s = math.sin(math.radians(a))
+
+        p1 = (0, 90-a, c*d)
+        p2 = (
+            d+t,
+            -90,
+            t*0.5,
+            135,
+            t*2**0.5,
+            135,
+            d+2*t+s*0.5*t)
+        p3 = (c*d-s*c*0.2*t, -a, 0)
+
+        if not reverse:
+            self.polyline(*p1)
+            self.corner(-180, r)
+            self.polyline(*p2)
+            self.corner(-180+2*a, r)
+            self.polyline(*p3)
+        else:
+            self.polyline(*reversed(p3))
+            self.corner(-180+2*a, r)
+            self.polyline(*reversed(p2))
+            self.corner(-180, r)
+            self.polyline(*reversed(p1))
+
+    def hookWidth(self):
+        t = self.thickness
+        a = self.settings.angle
+        d = self.settings.depth
+        r = self.settings.bottom_radius
+        c = math.cos(math.radians(a))
+        s = math.sin(math.radians(a))
+        return 2 * s * d * c + 0.5 * c * t + c * 4 * r
+
+    def hookOffset(self):
+        t = self.thickness
+        a = self.settings.angle
+        d = self.settings.depth
+        r = self.settings.bottom_radius
+        c = math.cos(math.radians(a))
+        s = math.sin(math.radians(a))
+        return s * d * c + 2 * r
+
+    def finger(self, length):
+        t = self.thickness
+        self.polyline(
+            2*t,
+            90,
+            length,
+            90,
+            2*t,
+        )
+
+    def __call__(self, length, **kw):
+        t = self.thickness
+        self.edge(4*t)
+        self.hook()
+        self.finger(2*t)
+        self.hook(reverse=True)
+
+        self.edge(length - 2* (6*t + 2*self.hookWidth()))
+
+        self.hook()
+        self.finger(2*t)
+        self.hook(reverse=True)
+        self.edge(4*t)
+
+    def margin(self):
+        return 2 * self.thickness
+
+class ClickEdge(ClickConnector):
+    char ="C"
+    description = "Click on (top)"
+
+    def startwidth(self):
+        return self.boxes.thickness
+
+    def margin(self):
+        return self.boxes.spacing
+
+    def __call__(self, length, **kw):
+        t = self.thickness
+        o = self.hookOffset()
+        w = self.hookWidth()
+        p1 = (
+            4*t + o,
+            90,
+            t,
+            -90,
+            2*(t+w-o),
+            -90,
+            t,
+            90,
+            0)
+        self.polyline(*p1)
+        self.edge(length - 2 * (6*t + 2* w) + 2*o)
+        self.polyline(*reversed(p1))
+
 #############################################################################
 ####     Dove Tail Joints
 #############################################################################