From 8b215460a13c51434f0213556f03e8535cf567ec Mon Sep 17 00:00:00 2001
From: Stewart Allen <stewart.allen@gmail.com>
Date: Sat, 29 Jun 2024 23:03:40 -0400
Subject: [PATCH] complete basic gerber import conversion to mesh for milling
 traces

---
 src/add/array.js            |  2 ++
 src/geo/csg.js              | 12 ++++++++++--
 src/geo/polygon.js          | 27 +++++++++++++++------------
 src/kiri-mode/cam/client.js |  8 ++++----
 src/kiri/platform.js        | 16 ++++++++++------
 src/load/gbr.js             | 30 ++++++++++++++++++++++++------
 6 files changed, 65 insertions(+), 30 deletions(-)

diff --git a/src/add/array.js b/src/add/array.js
index c9c603ce..e40b59e2 100644
--- a/src/add/array.js
+++ b/src/add/array.js
@@ -233,6 +233,8 @@ Float32Array.prototype.toShared = function() {
     return newvert;
 };
 
+Float32Array.prototype.toFloat32 = function() { return this };
+
 String.prototype.reverse = function() {
     return this.split('').reverse().join('');
 };
diff --git a/src/geo/csg.js b/src/geo/csg.js
index fc14225d..2433fdf7 100644
--- a/src/geo/csg.js
+++ b/src/geo/csg.js
@@ -9,6 +9,14 @@ gapp.register("geo.csg", [], (root, exports) => {
 const { base, ext } = root;
 const debug = true;
 
+function log() {
+    if (root?.mesh?.log) {
+        root.mesh.log(...arguments)
+    } else if (root.debug === true) {
+        console.log(...arguments);
+    }
+}
+
 const CSG = {
     // accepts 2 or more arguments with threejs vertex position arrays
     union() {
@@ -27,7 +35,7 @@ const CSG = {
     },
 
     moduleOp(name, op) {
-        mesh.log(`${name} ${arguments.length} meshes`);
+        log(`${name} ${arguments.length} meshes`);
         const args = [...arguments].slice(2).map(a => new Instance.Manifold(a));
         if (args.length < 2) {
             throw "missing one or more meshes";
@@ -80,7 +88,7 @@ const CSG = {
 };
 
 function indexVertices(pos) {
-    mesh.log(`indexing ${pos.length/3} vertices`);
+    log(`indexing ${pos.length/3} vertices`);
     let ipos = 0;
     const index = [];
     const vertices = [];
diff --git a/src/geo/polygon.js b/src/geo/polygon.js
index 414ca8c6..c52aab73 100644
--- a/src/geo/polygon.js
+++ b/src/geo/polygon.js
@@ -1852,39 +1852,42 @@ class Polygon {
     }
 
     // turn 2d polygon into a 2.5D ribbon extruded in Z
-    ribbonZ(z = 1) {
+    ribbonZ(z = 1, zadd = 0, rev) {
         let poly = this.clone().setClockwise();
         let faces = [];
         let points = poly.points;
         let length = points.length;
+        if (rev) {
+            points = points.slice().reverse();
+        }
         for (let i=0; i<length; i++) {
             let p0 = points[i];
             let p1 = points[(i + 1) % length];
-            faces.push(p0.x, p0.y, p0.z);
-            faces.push(p1.x, p1.y, p0.z);
-            faces.push(p1.x, p1.y, p1.z + z);
-            faces.push(p0.x, p0.y, p0.z);
-            faces.push(p1.x, p1.y, p1.z + z);
-            faces.push(p0.x, p0.y, p0.z + z);
+            faces.push(p0.x, p0.y, p0.z + zadd);
+            faces.push(p1.x, p1.y, p1.z + z + zadd);
+            faces.push(p1.x, p1.y, p0.z + zadd);
+            faces.push(p0.x, p0.y, p0.z + zadd);
+            faces.push(p0.x, p0.y, p0.z + z + zadd);
+            faces.push(p1.x, p1.y, p1.z + z + zadd);
         }
         return faces;
     }
 
     // extrude poly (with inner voids) into 3d mesh
-    extrude(z = 1) {
+    extrude(z = 1, zadd = 0) {
         let obj = [];
         let earcut = this.earcut();
         for (let poly of earcut) {
             for (let point of poly.points) {
-                obj.push(point.x, point.y, z);
+                obj.push(point.x, point.y, z + zadd);
             }
             for (let point of poly.points.reverse()) {
-                obj.push(point.x, point.y, 0);
+                obj.push(point.x, point.y, zadd);
             }
         }
-        obj.appendAll(this.ribbonZ(z));
+        obj.appendAll(this.ribbonZ(z, zadd));
         for (let inner of this.inner || []) {
-            obj.appendAll(inner.ribbonZ(z));
+            obj.appendAll(inner.ribbonZ(z, zadd, true));
         }
         return obj;
     }
diff --git a/src/kiri-mode/cam/client.js b/src/kiri-mode/cam/client.js
index 72c28ba6..da44193d 100644
--- a/src/kiri-mode/cam/client.js
+++ b/src/kiri-mode/cam/client.js
@@ -116,10 +116,10 @@ CAM.init = function(kiri, api) {
         updateStock();
     }
 
-    api.event.on("cam.parse.gerber", gerber => {
-        const { open, closed, circs, rects } = load.GBR.parse(gerber);
-        const widget = api.widgets.all()[0];
-        const stack = new kiri.Stack(widget.mesh);
+    api.event.on("cam.parse.gerber", opts => {
+        const { data, mesh } = opts;
+        const { open, closed, circs, rects } = load.GBR.parse(data);
+        const stack = new kiri.Stack(mesh || moto.space.world.newGroup());
         const layers = new kiri.Layers();
         for (let poly of open) {
             layers.setLayer("open", {line: 0xff8800}, false).addPoly(poly);
diff --git a/src/kiri/platform.js b/src/kiri/platform.js
index 719392bb..24fa52a5 100644
--- a/src/kiri/platform.js
+++ b/src/kiri/platform.js
@@ -819,17 +819,21 @@ function platformLoadFiles(files, group) {
                 } else {
                     odon();
                 }
-            } else if (isgbr && api.conf.get().controller.devel) {
-                if (api.mode.is_cam()) {
-                    api.event.emit('cam.parse.gerber', e.target.result);
+            } else if (isgbr) {
+                if (api.conf.get().controller.devel) {
+                    api.event.emit('cam.parse.gerber', { data: e.target.result });
                 } else {
                     let mesh = load.GBR.toMesh(e.target.result);
-                    platform.add(
+                    let wid;
+                    platform.add(wid =
                         newWidget(undefined, group)
-                        .loadVertices(mesh.toFloat32(), true)
+                        .loadVertices(mesh, true)
                         .saveToCatalog(e.target.file.name)
                     );
-                    // api.alerts.show('Gerber import not availabe in this device mode');
+                    if (api.mode.is_cam()) {
+                        // attach raw illustration
+                        api.event.emit('cam.parse.gerber', { data: e.target.result, mesh: wid.mesh });
+                    }
                 }
             } else if (is3mf) {
                 let odon = function(models) {
diff --git a/src/load/gbr.js b/src/load/gbr.js
index 0ff4d30d..e53edd4a 100644
--- a/src/load/gbr.js
+++ b/src/load/gbr.js
@@ -4,24 +4,42 @@
 // use: geo.polygon
 // use: geo.polygons
 // use: ext.gerber
+// use: geo.csg
 gapp.register("load.gbr", (root, exports) => {
 
 const { load } = root;
+const POLYS = base.polygons;
+const CSG = base.CSG;
 
 load.GBR = {
     parse,
     toMesh
 };
 
-function toMesh(text, opt = { z: 3 }) {
+function toMesh(text, opt = { z: 1 }) {
     const { open, closed, circs, rects } =  parse(text);
+
     const nest = base.polygons.nest([...closed, ...circs, ...rects], true);
-    console.log({ nest });
-    const obj = [];
-    for (let poly of nest) {
-        obj.appendAll(poly.extrude(opt.z || 3));
+
+    const flat = POLYS.flatten(nest, [], true);
+    const z0 = opt.z  || opt.z0 || 1;
+    const z1 = opt.z1 || 0.25;
+
+    const top = [];
+    for (let poly of flat.filter(p => p.depth === 0)) {
+        top.push(poly.extrude(z0));
     }
-    return obj;
+
+    const mid = [];
+    for (let poly of flat.filter(p => p.depth === 1)) {
+        mid.push(poly.extrude(z1, z0 - z1));
+    }
+
+    const topMesh = CSG.fromPositionArray(top[0]);
+    const midMesh = mid.map(v => CSG.fromPositionArray(v));
+    const subMesh = CSG.subtract(topMesh, ...midMesh);
+
+    return CSG.toPositionArray(subMesh);
 }
 
 function parse(text) {