add utility functions for rounded keycaps and flesh out some comments

keys.scad

@@ -1,8 +1,16 @@
+// the point of this file is to be a sort of DSL for constructing keycaps.
+// when you create a method chain you are just changing the parameters
+// key.scad uses, it doesn't generate anything itself until the end. This
+// makes it remain easy to use key.scad like before (except without key profiles)
+// without having to rely on this file. Unfortunately that means setting tons of
+// special variables, but that's a limitation of SCAD we'll have to work around
+
 /* TODO:
- * can now measure keycaps very accurately. need to redo measurements
+ * can now measure keycaps very accurately. need to redo measurements: [x] SA [ ] DCS [ ] DSA [ ] OEM?
+ * bowed sides for SA? jebus
  * sideways cylindrical dish needs to be used for some spacebars but not others. currently none of them use it
  * Add inset stem to all profiles that need it
- * Pregenerated keysets
+ * Pregenerated keysets for DCS (rounded tops too intense) [ ] 60% [ ] TKL [ ] full
  * Full experimental ISO enter
  * customizer version where everything is copy/pasted in
  */

util.scad

@@ -20,3 +20,29 @@ module roundedRect(size, radius) {
 		circle(r=radius);
 	}
 }
+
+module functional_scaled_extrude(height = 10, slices=[]) {
+	nominal_height = height / (len(slices) - 1);
+	for (index = [0 : len(slices)-2]){
+		slice1 = slices[index];
+		slice2 = slices[index+1];
+		echo(slice2);
+		hull(){
+			translate([0,0,nominal_height * index]) {
+				scale(slice1) children();
+			}
+			translate([0,0,nominal_height * (index + 1)]) {
+				scale(slice2) children();
+			}
+		}
+	}
+}
+
+module progressive_hull() {
+  for (i = [0 : $children-2]){
+		hull(){
+			children(i);
+			children(i+1);
+		}
+	}
+}