Rewrite keystone.scad (#35)

* helper/keystone: rewrite completely

* rack-mount/patch-panel: edit to adapt to the new keystone

* helper/keystone: fill the lug-side opening

* rack-mount/patch-panel: allow combining two types of keystones and
plates freely

* rack-mount/patch-panel/entry: apply suggestions

Co-authored-by: Zhao (Jack) Wang <jazwang@proton.me>

* rack-mount/patch-panel: fix animate.scad & regen gif

---------

Co-authored-by: Zhao (Jack) Wang <jazwang@proton.me>

helper/keystone2.scad

@@ -0,0 +1,42 @@
+include <../config/common.scad>
+
+//   These all constants are obtained by measuring rj45 keystone modules
+// in hand. frontToRearDepth and rearPanelThickness are adjusted after testing.
+// Before printing the Patch Panel, print a keystone2(outerWidth = 19,
+// outerHeight = 27) to test if it fits.
+frontWidth = 14.5;
+frontHeight = 16.2;
+
+frontToRearDepth = 8.4;
+
+rearWidth = frontWidth;
+rearHeight = 19.55;
+rearPanelThickness = 2 - supportedOverhangSlack;
+
+maximumWidth = frontWidth;
+maximumHeight = 22.15;
+
+lugHeight = 1.3;
+
+module keystone2(plateThickness = 1, outerWidth, outerHeight) {
+    assert(outerWidth > maximumWidth);
+    assert(outerHeight > maximumHeight);
+
+    difference() {
+        // Outer cube
+        translate([-outerWidth / 2, -outerHeight / 2, 0])
+        cube([outerWidth, outerHeight, frontToRearDepth + rearPanelThickness]);
+
+        // Front panel hole
+        translate([-(frontWidth + xySlack) / 2, -(frontHeight + xySlack) / 2, 0])
+        cube([frontWidth + xySlack, frontHeight + xySlack, plateThickness]);
+
+        // Middle cavity
+        translate([-(maximumWidth + xySlack) / 2, -frontHeight / 2 - lugHeight - xySlack / 2, plateThickness])
+        cube([rearWidth + xySlack, outerHeight + 1000, frontToRearDepth - plateThickness]);
+
+        // Rear panel hole
+        translate([-(rearWidth + xySlack) / 2, -(frontHeight + xySlack) / 2, frontToRearDepth])
+        cube([rearWidth + xySlack, rearHeight + xySlack, rearPanelThickness]);
+    }
+}