From c1501c7739b3b809593315d827c9d922f265d699 Mon Sep 17 00:00:00 2001
From: Stewart Allen <sa@grid.space>
Date: Mon, 10 Oct 2022 16:08:01 -0400
Subject: [PATCH] add Z refining passes to complement XY smoothing in pocket
 contours

---
 src/geo/paths.js            |  4 +++-
 src/kiri-mode/cam/client.js |  2 ++
 src/kiri-mode/cam/ops.js    | 38 ++++++++++++++++++++++++++++++++++---
 src/kiri/conf.js            |  1 +
 web/kiri/lang/en.js         |  4 +++-
 5 files changed, 44 insertions(+), 5 deletions(-)

diff --git a/src/geo/paths.js b/src/geo/paths.js
index 14f02588..b01a9b8d 100644
--- a/src/geo/paths.js
+++ b/src/geo/paths.js
@@ -456,7 +456,9 @@ base.paths = {
     tip2tipEmit,
     shapeToPath,
     pointsToPath,
-    pathTo3D
+    pathTo3D,
+    vertexNormal: calc_vertex,
+    segmentNormal: calc_normal
 };
 
 });
diff --git a/src/kiri-mode/cam/client.js b/src/kiri-mode/cam/client.js
index f5e88edf..c8de7c14 100644
--- a/src/kiri-mode/cam/client.js
+++ b/src/kiri-mode/cam/client.js
@@ -1142,6 +1142,7 @@ CAM.init = function(kiri, api) {
         plunge:    'camPocketPlunge',
         expand:    'camPocketExpand',
         smooth:    'camPocketSmooth',
+        refine:    'cmaPocketRefine',
         contour:   'camPocketContour',
         outline:   'cmaPocketOutline',
         tolerance: 'camTolerance',
@@ -1155,6 +1156,7 @@ CAM.init = function(kiri, api) {
         plunge:    UC.newInput(LANG.cc_plng_s, {title:LANG.cc_plng_l, convert:UC.toInt, units:true}),
         sep:       UC.newBlank({class:"pop-sep"}),
         expand:    UC.newInput(LANG.cp_xpnd_s, {title:LANG.cp_xpnd_l, convert:UC.toFloat, units:true, show:() => !poppedRec.contour}),
+        refine:    UC.newInput(LANG.cp_refi_s, {title:LANG.cp_refi_l, convert:UC.toInt, show:() => poppedRec.contour}),
         smooth:    UC.newInput(LANG.cp_smoo_s, {title:LANG.cp_smoo_l, convert:UC.toFloat, units:true}),
         tolerance: UC.newInput(LANG.ou_toll_s, {title:LANG.ou_toll_l, convert:UC.toFloat, bound:UC.bound(0,10.0), units:true, round:4, show:() => poppedRec.contour}),
         sep:       UC.newBlank({class:"pop-sep"}),
diff --git a/src/kiri-mode/cam/ops.js b/src/kiri-mode/cam/ops.js
index 4c5aa4a8..c2ebfe5e 100644
--- a/src/kiri-mode/cam/ops.js
+++ b/src/kiri-mode/cam/ops.js
@@ -13,7 +13,7 @@ gapp.register("kiri-mode.cam.ops", [], (root, exports) => {
 
 const { base, kiri } = root;
 const { paths, polygons, newPoint, newPolygon, sliceConnect } = base;
-const { poly2polyEmit, tip2tipEmit } = paths;
+const { poly2polyEmit, tip2tipEmit, segmentNormal, vertexNormal } = paths;
 const { driver, newSlice } = kiri;
 const { CAM } = driver;
 
@@ -1045,7 +1045,7 @@ class OpPocket extends CamOp {
                     }
                     POLY.setWinding(slice.camLines, cutdir, false);
                     if (contour) {
-                        slice.camLines = pocket.conform(slice.camLines);
+                        slice.camLines = pocket.conform(slice.camLines, op.refine);
                     }
                     slice.output()
                         .setLayer("pocket", {line: color}, false)
@@ -1093,14 +1093,46 @@ class OpPocket extends CamOp {
     }
 
     // mold cam output lines to the surface of the topo offset by tool geometry
-    conform(camLines) {
+    conform(camLines, refine = 10) {
         const topo = this.topo;
+        // re-segment polygon to a higher resolution
         const hirez = camLines.map(p => p.segment(topo.tolerance * 2));
+        // walk points and offset from surface taking into account tool geometry
         for (let poly of hirez) {
             for (let point of poly.points) {
                 point.z = topo.toolAtXY(point.x, point.y);
             }
         }
+        // walk points noting z deltas and smoothing sawtooth patterns
+        for (let j=0; j<refine; j++)
+        for (let poly of hirez) {
+            const points = poly.points, length = points.length;
+            let sn = []; // segment normals
+            let dz = []; // z deltas
+            for (let i=0; i<length; i++) {
+                let p1 = points[i];
+                let p2 = points[(i + 1) % length];
+                dz.push(p1.z - p2.z);
+                sn.push(segmentNormal(p1, p2));
+            }
+            let vn = []; // vertex normals
+            for (let i=0; i<length; i++) {
+                let n1 = sn[(i + length - 1) % length];
+                let n2 = sn[i];
+                let vi = vertexNormal(n1, n2, 1);
+                vn.push(vi);
+                let vl = Math.abs(1 - vi.vl).round(2);
+                // vl should be close to zero on smooth / continuous curves
+                // factoring out hard turns, we smooth the z using the weighted
+                // z values of the points before and after the current point
+                if (vl === 0) {
+                    let p0 = points[(i + length - 1) % length];
+                    let p1 = points[i];
+                    let p2 = points[(i + 1) % length];
+                    p1.z = (p0.z + p2.z + p1.z) / 3;
+                }
+            }
+        }
         return hirez;
     }
 
diff --git a/src/kiri/conf.js b/src/kiri/conf.js
index 166ae687..46e9c9ee 100644
--- a/src/kiri/conf.js
+++ b/src/kiri/conf.js
@@ -510,6 +510,7 @@ const conf = exports({
                 camPocketPlunge: 200,
                 camPocketExpand: 0,
                 camPocketSmooth: 0,
+                cmaPocketRefine: 20,
                 camPocketContour: false,
                 cmaPocketOutline: false,
                 camDrillTool: 1000,
diff --git a/web/kiri/lang/en.js b/web/kiri/lang/en.js
index 79489063..3da861bb 100644
--- a/web/kiri/lang/en.js
+++ b/web/kiri/lang/en.js
@@ -516,7 +516,9 @@ self.kiri.lang['en-us'] = {
     cp_xpnd_s:      "expand",
     cp_xpnd_l:      ["grow selected area to","encompass corners"],
     cp_smoo_s:      "smooth",
-    cp_smoo_l:      ["clean up jagged edges caused by angled walls. can speedup and improve pocketing for detailed geometries. recommend starting with values around 1"],
+    cp_smoo_l:      ["clean up jagged edges caused by angled walls. can speedup and improve pocketing for detailed geometries. recommend starting with values around 1 if slicing takes too long or the contours look jagged"],
+    cp_refi_s:      "refine",
+    cp_refi_l:      ["number of refining passes to perform on contoured polylines. meant to address Z delta sawtoothing caused by faced geometries whereas smoothing handles XY. values > 10 work well for gently contoured geometries with significant Z movement."],
     cp_cont_s:      "contour",
     cp_cont_l:      ["ignore interior voids and features"],
     cp_outl_s:      "outline only",