fix the splitting logic

Author: sophiedeziel

src/__tests__/job.ts

@@ -96,16 +96,16 @@ describe('.layers', () => {
     expect(layers[0].paths.length).toEqual(2);
   });
 
-  test('travel paths moving z above the default tolerance create a new layer', () => {
+  test('extrusion paths moving z above the default tolerance create a new layer', () => {
     const job = new Job();
 
     append_path(job, PathType.Extrusion, [
       [0, 0, 0],
       [1, 2, 0]
     ]);
-    append_path(job, PathType.Travel, [
-      [5, 6, 0],
-      [5, 6, LayersIndexer.DEFAULT_TOLERANCE + 0.01]
+    append_path(job, PathType.Extrusion, [
+      [5, 6, LayersIndexer.DEFAULT_TOLERANCE + 0.02],
+      [5, 6, LayersIndexer.DEFAULT_TOLERANCE + 0.02]
     ]);
 
     const layers = job.layers;
@@ -181,9 +181,8 @@ describe('.layers', () => {
 
     expect(layers).not.toBeNull();
     expect(layers).toBeInstanceOf(Array);
-    expect(layers.length).toEqual(2);
-    expect(layers[0].paths.length).toEqual(1);
-    expect(layers[1].paths.length).toEqual(3);
+    expect(layers.length).toEqual(1);
+    expect(layers[0].paths.length).toEqual(4);
   });
 
   test('extrusions after travels are on the same layer', () => {
@@ -215,8 +214,8 @@ describe('.layers', () => {
     expect(layers).not.toBeNull();
     expect(layers).toBeInstanceOf(Array);
     expect(layers.length).toEqual(2);
-    expect(layers[0].paths.length).toEqual(1);
-    expect(layers[1].paths.length).toEqual(4);
+    expect(layers[0].paths.length).toEqual(4);
+    expect(layers[1].paths.length).toEqual(1);
   });
 });
 

src/job.ts

@@ -152,31 +152,23 @@ export class LayersIndexer extends Indexer {
   }
 
   sortIn(path: Path): void {
-    if (path.travelType === PathType.Extrusion && path.vertices.some((_, i, arr) => i % 3 === 2 && arr[i] !== arr[2])) {
+    if (
+      path.travelType === PathType.Extrusion &&
+      path.vertices.some((_, i, arr) => i % 3 === 2 && arr[i] - arr[2] >= this.tolerance)
+    ) {
       throw new NonPlanarPathError();
     }
+
     if (this.indexes[this.indexes.length - 1] === undefined) {
       this.createLayer(path.vertices[2]);
     }
 
     if (path.travelType === PathType.Extrusion) {
-      this.lastLayer().paths.push(path);
-    } else {
-      const verticalTravels = path.vertices
-        .map((_, i, arr) => {
-          if (i % 3 === 2 && arr[i] - arr[2] > this.tolerance) {
-            return arr[i] - arr[2];
-          }
-        })
-        .filter((z) => z !== undefined);
-      const hasVerticalTravel = verticalTravels.length > 0;
-      const hasExtrusions = this.lastLayer().paths.find((p) => p.travelType === PathType.Extrusion);
-
-      if (hasVerticalTravel && hasExtrusions) {
+      if (path.vertices[2] - (this.lastLayer().z || 0) > this.tolerance) {
         this.createLayer(path.vertices[2]);
       }
-      this.lastLayer().paths.push(path);
     }
+    this.lastLayer().paths.push(path);
   }
 
   private lastLayer(): Layer {