From 3754009a435d4f2287e432a033931d46add0e476 Mon Sep 17 00:00:00 2001
From: Joel Ebel <jbebel@google.com>
Date: Fri, 18 May 2018 00:24:54 -0400
Subject: [PATCH] Make RoundBox smarter to reduce code duplication

RoundBox now takes an xshrink and yzshrink argument, which tell it how
much to shrink the box from the Length, Width, and Height parameters.
They defaul to 0. The removes the need to translate the calls to
RoundBox or to repeatedly provide adjustments to its arguments that are
very similar. As a result, the MainBox module is now much simpler and
easier to understand.
---
 files/U_Box_V104_Test_Cleaned.scad | 51 +++++++++++++-----------------
 1 file changed, 22 insertions(+), 29 deletions(-)

diff --git a/files/U_Box_V104_Test_Cleaned.scad b/files/U_Box_V104_Test_Cleaned.scad
index 3672a32..942628f 100644
--- a/files/U_Box_V104_Test_Cleaned.scad
+++ b/files/U_Box_V104_Test_Cleaned.scad
@@ -160,16 +160,17 @@ LeftEdgeOfBoardWRTBPanel = RightEdgeMargin - (PanelGap/2);
     Filet and Resolution parameters.
     
     Arguments:
-    a: The length of the box. Defaults to "Length" parameter.
-    b: The width of the box. Defaults to the "Width" parameter.
-    c: The height of the box. Defaults to the "Height" parameter.   
+    xshrink: the amount to reduce the length on one end compared to the full length
+    yzshrink: the amount to reduce the width or height on one edge compared to the full box  
 */
-module RoundBox($a=Length, $b=Width, $c=Height) {
-    rotate([90, 0, 90]) {
-        linear_extrude(height=$a) {
-            translate([Filet, Filet, 0]) {
-                offset(r=Filet, $fn=Resolution) {
-                    square([$b - 2*Filet, $c - 2*Filet]);
+module RoundBox(xshrink=0, yzshrink=0) {
+    translate([xshrink, yzshrink, yzshrink]) {
+        rotate([90, 0, 90]) {
+            linear_extrude(height=Length - xshrink*2) {
+                translate([Filet, Filet, 0]) {
+                    offset(r=Filet, $fn=Resolution) {
+                        square([Width - 2*yzshrink - 2*Filet, Height - 2*yzshrink - 2*Filet]);
+                    }
                 }
             }
         }
@@ -185,31 +186,23 @@ module RoundBox($a=Length, $b=Width, $c=Height) {
 module MainBox() {
     difference() {
         union() {
-            difference() { // Makes a hollow box with walls of Thick thickness.
+            // Makes a hollow box with walls of Thick thickness.
+            difference() {
                 RoundBox();
-                translate([Thick, Thick, Thick]) {
-                    RoundBox($a=(Length - Thick*2),
-                             $b=(Width - Thick*2),
-                             $c=(Height - Thick*2));
-                }
+                RoundBox(xshrink=Thick, yzshrink=Thick);
             }
-            difference() { // Makes interior backing for panel
-                translate([Thick + PanelThick + PanelGap, Thick/2, Thick/2]) { // Rails
-                     RoundBox($a=(Length - ((Thick + PanelThick + PanelGap)*2)),
-                              $b=(Width - Thick),
-                              $c=(Height - Thick));
-                }
-                translate([Thick*2 + PanelThick + PanelGap, 0, 0]) {
-                     RoundBox($a=(Length - ((Thick*2 + PanelThick + PanelGap) * 2)));
-                }
+            // Makes interior backing for panel as a wall
+            difference() {
+                RoundBox(xshrink=(Thick + PanelThick + PanelGap), yzshrink=Thick/2);
+                RoundBox(xshrink=(Thick*2 + PanelThick + PanelGap));
             }
-        } // /union
-        translate([-Thick, -Thick, Height/2]) { // Remove the top half
+        }
+        // Remove the top half
+        translate([-Thick, -Thick, Height/2]) {
             cube([Length + Thick*2, Width + Thick*2, Height]);
         }
-        translate([-Thick, Thick*2, Thick*2]) { // Remove the center for panel visibility.
-            RoundBox($a=(Length + Thick*2), $b=(Width - Thick*4), $c=(Height - Thick*4));
-        }
+        // Remove the center for panel visibility.
+        RoundBox(xshrink=-Thick, yzshrink=Thick*2);
     }
 }