Added more flexibility to get_named_args(), and all the left_half(), etc. as functions

arrays.scad

@@ -89,6 +89,18 @@ function select(list, start, end=undef) =
             :   concat([for (i = [s:1:l-1]) list[i]], [for (i = [0:1:e]) list[i]]) ;
 
 
+// Function: last()
+// Description:
+//   Returns the last element of a list, or undef if empty.
+// Usage:
+//   last(list)
+// Arguments:
+//   list = The list to get the last element of.
+// Example:
+//   l = [3,4,5,6,7,8,9];
+//   last(l);  // Returns 9.
+function last(list) = list[len(list)-1];
+
 // Function: slice()
 // Description:
 //   Returns a slice of a list.  The first item is index 0.

common.scad

@@ -312,27 +312,41 @@ function get_height(h=undef,l=undef,height=undef,dflt=undef) =
     assert(num_defined([h,l,height])<=1,"You must specify only one of `l`, `h`, and `height`")
     first_defined([h,l,height,dflt]);
 
-// Function: get_named_args(anonymous, named, _undef)
+// Function: get_named_args(positional, named, _undef)
 // Usage:
-// function f(anon1=_undef, anon2=_undef,...,
+// function f(pos1=_undef, pos2=_undef,...,
 //     named1=_undef, named2=_undef, ...) =
-//     let(args = get_named_args([anon1, anon2, ...],
+//     let(args = get_named_args([pos1, pos2, ...],
-//        [[named1, default1], [named2, default2], ...]))
+//        [[named1, default1], [named2, default2], ...]),
+//        named1=args[0], named2=args[1], ...)
 //        ...
 // Description:
-//   given a set of anonymous and named arguments, returns the values of
+//   Given the values of some positional and named arguments,
-//   named arguments, in order.
+//   returns a list of the values assigned to named arguments,
-//    - All named arguments which were provided by the user take the
+//   in the following way:
-//    value provided.
+//    - All named arguments which were explicitly assigned in the
+//    function call take the value provided.
 //    - All named arguments which were not provided by the user are
-//    affected from anonymous arguments, in order.
+//    affected from positional arguments; the priority order in which
+//    these are assigned is given by the `priority` argument, while the
+//    positional assignation is done in the order of the named arguments.
 //    - Any remaining named arguments take the provided default values.
 // Arguments:
-//   anonymous = the list of values of anonymous arguments.
+//   positional = the list of values of positional arguments.
-//   named = the list of [passed-value, default value] of named arguments.
+//   named = the list of named arguments; each entry of the list has the
-//   _undef = the default value used by the calling function for all
+//   form [passed-value, default-value, priority], where
-//   arguments (this is *not* undef, or any value that the user might
+//      passed-value is the value that was passed at function call;
-//   purposely want to use as an argument value).
+//      default-value is the value that will be used if nothing is read
+//      from either named or positional arguments;
+//      priority is the priority assigned to this argument.
+//   _undef = the default value used by the calling function for all arguments (default is some random string that you will never use). (this is *not* undef, or any value that the user might purposely want to use as an argument value).
+//
+//  If only k positional arguments are used, then the k named values
+//  with lowest 'priority' value (among the unassigned ones) will get them.
+//  The arguments will be assigned in the order of the named values.
+//  By default these two orders coincide.
+//
+//
 // Examples:
 // function f(arg1=_undef, arg2=_undef, arg3=_undef,
 //   named1=_undef, named2=_undef, named3=_undef) =
@@ -349,16 +363,29 @@ function get_height(h=undef,l=undef,height=undef,dflt=undef) =
 // result of `dd if=/dev/random bs=32 count=1 |base64` :
 _undef="LRG+HX7dy89RyHvDlAKvb9Y04OTuaikpx205CTh8BSI";
 
-function get_named_args(anonymous, named,_undef=_undef) =
+/* Note: however tempting it might be, it is *not* possible to accept
-    /* u: set of undefined indices in named arguments */
+ * named argument as a list [named1, named2, ...] (without default
-    let(from_anon = [for(p=enumerate(named)) if(p[1][0]==_undef) p[0]],
+ * values), because the values [named1, named2...] themselves might be
-        n = len(anonymous))
+ * lists, and we will not be able to distinguish the two cases. */
-    echo("from_anon:", from_anon)
+function get_named_args(positional, named,_undef=_undef) =
+    let(deft = [for(p=named) p[1]], // default is undef
+        // indices of the values to fetch from positional args:
+        unknown = [for(x=enumerate(named)) if(x[1][0]==_undef) x[0]],
+        // number of values given to positional arguments:
+        n_positional = count_true([for(p=positional) p!=_undef]))
+    assert(n_positional <= len(unknown),
+      str("too many positional arguments (", n_positional, " given, ",
+          len(unknown), " required)"))
+    let(
+        // those elements which have no priority assigned go last (prio=+∞):
+        prio = sortidx([for(u=unknown) default(named[u][2], 1/0)]),
+        // list of indices of values assigned from positional arguments:
+        assigned = sort([for(i=[0:1:n_positional-1]) prio[i]]))
     [ for(e = enumerate(named))
-        // if the value is defined, return it:
+      let(idx=e[0], val=e[1][0], ass=search(idx, assigned))
-        e[1][0] != _undef ? e[1][0] :
+        val != _undef ? val :
-        let(k = anonymous[search(e[0], from_anon)[0]])
+        ass != [] ? positional[ass[0]] :
-        k != _undef ? k : e[1][1] ];
+        deft[idx] ];
 // Function: scalar_vec3()
 // Usage:
 //   scalar_vec3(v, <dflt>);

mutators.scad

@@ -121,16 +121,9 @@ module half_of(v=UP, cp, s=1000, planar=false)
 function half_of(_arg1=_undef, _arg2=_undef, _arg3=_undef, _arg4=_undef,
     v=_undef, cp=_undef, p=_undef, s=_undef) =
     let(args=get_named_args([_arg1, _arg2, _arg3, _arg4],
-        [[v], [cp, 0], [p], [s, 1e4]]),
+        [[v,undef,0], [cp,0,2], [p,undef,1], [s,1e4,3]]),
         v=args[0], cp0=args[1], p=args[2], s=args[3],
         cp = is_num(cp0) ? cp0*unit(v) : cp0)
-    echo("_undef=", _undef)
-    echo("v=", v)
-    echo("cp=", cp)
-    echo("p=", p)
-    echo("vnf?", is_vnf(p))
-    echo("region?", is_region(p))
-    echo("s=", s)
     assert(is_vector(v,2)||is_vector(v,3),
       "must provide a half-plane or half-space")
     let(d=len(v))
@@ -164,11 +157,15 @@ function half_of(_arg1=_undef, _arg2=_undef, _arg3=_undef, _arg4=_undef,
         :
     assert(false, "must pass either a point, a path, a region, or a VNF");
 
-// Module: left_half()
+// Function&Module: left_half()
 //
-// Usage:
+// Usage: as module
 //   left_half([s], [x]) ...
 //   left_half(planar=true, [s], [x]) ...
+// Usage: as function
+//   left_half([s], [x], path)
+//   left_half([s], [x], region)
+//   left_half([s], [x], vnf)
 //
 // Description:
 //   Slices an object at a vertical Y-Z cut plane, and masks away everything that is right of it.
@@ -197,10 +194,16 @@ module left_half(s=1000, x=0, planar=false)
         }
     }
 }
+function left_half(_arg1=_undef, _arg2=_undef, _arg3=_undef,
+    x=_undef, p=_undef, s=_undef) =
+    let(args=get_named_args([_arg1, _arg2, _arg3],
+    [[x, 0,1], [p,undef,0], [s, 1e4,2]]),
+        x=args[0], p=args[1], s=args[2])
+    half_of(v=[1,0,0], cp=x, p=p);
 
 
 
-// Module: right_half()
+// Function&Module: right_half()
 //
 // Usage:
 //   right_half([s], [x]) ...
@@ -233,10 +236,16 @@ module right_half(s=1000, x=0, planar=false)
         }
     }
 }
+function right_half(_arg1=_undef, _arg2=_undef, _arg3=_undef,
+    x=_undef, p=_undef, s=_undef) =
+    let(args=get_named_args([_arg1, _arg2, _arg3],
+    [[x, 0,1], [p,undef,0], [s, 1e4,2]]),
+        x=args[0], p=args[1], s=args[2])
+    half_of(v=[-1,0,0], cp=x, p=p);
 
 
 
-// Module: front_half()
+// Function&Module: front_half()
 //
 // Usage:
 //   front_half([s], [y]) ...
@@ -269,10 +278,16 @@ module front_half(s=1000, y=0, planar=false)
         }
     }
 }
+function front_half(_arg1=_undef, _arg2=_undef, _arg3=_undef,
+    x=_undef, p=_undef, s=_undef) =
+    let(args=get_named_args([_arg1, _arg2, _arg3],
+    [[x, 0,1], [p,undef,0], [s, 1e4,2]]),
+        x=args[0], p=args[1], s=args[2])
+    half_of(v=[0,1,0], cp=x, p=p);
 
 
 
-// Module: back_half()
+// Function&Module: back_half()
 //
 // Usage:
 //   back_half([s], [y]) ...
@@ -305,10 +320,16 @@ module back_half(s=1000, y=0, planar=false)
         }
     }
 }
+function back_half(_arg1=_undef, _arg2=_undef, _arg3=_undef,
+    x=_undef, p=_undef, s=_undef) =
+    let(args=get_named_args([_arg1, _arg2, _arg3],
+    [[x, 0,1], [p,undef,0], [s, 1e4,2]]),
+        x=args[0], p=args[1], s=args[2])
+    half_of(v=[0,-1,0], cp=x, p=p);
 
 
 
-// Module: bottom_half()
+// Function&Module: bottom_half()
 //
 // Usage:
 //   bottom_half([s], [z]) ...
@@ -333,10 +354,16 @@ module bottom_half(s=1000, z=0)
         }
     }
 }
+function right_half(_arg1=_undef, _arg2=_undef, _arg3=_undef,
+    x=_undef, p=_undef, s=_undef) =
+    let(args=get_named_args([_arg1, _arg2, _arg3],
+    [[x, 0,1], [p,undef,0], [s, 1e4,2]]),
+        x=args[0], p=args[1], s=args[2])
+    half_of(v=[0,0,-1], cp=x, p=p);
 
 
 
-// Module: top_half()
+// Function&Module: top_half()
 //
 // Usage:
 //   top_half([s], [z]) ...
@@ -361,6 +388,12 @@ module top_half(s=1000, z=0)
         }
     }
 }
+function right_half(_arg1=_undef, _arg2=_undef, _arg3=_undef,
+    x=_undef, p=_undef, s=_undef) =
+    let(args=get_named_args([_arg1, _arg2, _arg3],
+    [[x, 0,1], [p,undef,0], [s, 1e4,2]]),
+        x=args[0], p=args[1], s=args[2])
+    half_of(v=[0,0,1], cp=x, p=p);
 
 
 

vnf.scad

@@ -924,7 +924,7 @@ function _vnf_halfspace_paths(edges, i=0, paths=[]) =
  */
    i >= len(edges) ? paths : // termination condition
    let(e = edges[i],
-       s = [for(x=enumerate(paths)) if(x[1][len(x[1])-1] == e[0]) x[0]])
+       s = [for(x=enumerate(paths)) if(last(x[1]) == e[0]) x[0]])
    _vnf_halfspace_paths(edges, i+1,
    // if cannot attach to previous path: create a new one
        s == [] ? concat(paths, [e]) :
@@ -947,7 +947,7 @@ function vnf_halfspace(_arg1=_undef, _arg2=_undef,
         newedges=[for(x=tmp2) each x[1]],
         // generate new faces
         paths=_vnf_halfspace_paths(newedges),
-        loops=[for(p=paths) if(p[0] == p[len(p)-1]) p])
+        loops=[for(p=paths) if(p[0] == last(p)) p])
     [coords, concat(newfaces, loops)];
 
 //