From cf1e97643aff2ec1c094b2c948e86affedb13285 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Mon, 21 Apr 2025 12:12:35 +0100
Subject: [PATCH] toolbox-inserts: fix z

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 toolbox-inserts.scad | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/toolbox-inserts.scad b/toolbox-inserts.scad
index 2337d6b..79b7c26 100644
--- a/toolbox-inserts.scad
+++ b/toolbox-inserts.scad
@@ -61,11 +61,10 @@ module AtFixingPositions(screws) {
 //     SomethingPositive();
 // }
 //
-// SomethingPositive must extend in z
-//     from -half_height to at least 0, and probably to half_height
-// IOW its z==0 must be where the top of the wall is,
-// and half_height is the depth of the well below that.
+// SomethingPositive is the representation of the object to be retained
+// Retaining walls will be made up to its z=0.
 module WellSurround(
+  // Amount by which the object protrudes above z==0
   half_height,
   // gaps for picking up object, [ [ x_min, x_max ], ... ]
   gaps,
@@ -78,13 +77,15 @@ module WellSurround(
   wall=well_surround_wall
 ) {
 
+  dz = box_main_z - below_plane_z - half_height;
+
   render() difference(){
 //    minkowski(){
 //      WallMinkowskiSphere(wall);
 
     difference(){
       union(){
-	translate(concat(offset, [0])) linextr(-10, half_height){
+	translate(concat(offset, [0])) linextr(-10, dz){
 	  offset($fn=8, r = wall)
 	    projection(cut=false)
 	    children(0);
@@ -106,7 +107,7 @@ module WellSurround(
 
 //	minkowski(){
 //	  WallMinkowskiSphere(wall);
-      translate(concat(offset, [0])) translate([0, 0, half_height]) {
+      translate(concat(offset, [0])) translate([0, 0, dz]) {
 	children(0);
       }
 //	}
@@ -178,3 +179,16 @@ module OverallDemo() { ////toplevel
   color("grey") BoxBottomModel();
   color("red") OdAt(-5,-5) DriverHandleHolder();
 }
+
+module OverallDemoLidded() { ////toplevel
+  OverallDemo();
+
+  %translate([0,0, box_main_z - below_plane_z*2])
+     rotate([180,0,0])
+     BoxBottomModel();
+
+  color("yellow")
+    translate([-box_x/2 - 5, 0, -below_plane_z])
+    linextr(0, box_main_z)
+    circle(r=3, $fn=3);
+}
-- 
2.30.2