add class notes. check for gl lost context

src/kiri/layers.js

@@ -2,6 +2,12 @@
 
 "use strict";
 
+/*
+ * provides the `output` abstraction for turning poly lines (open and closed)
+ * into primordial geometries (faces, lines, color ranges). used inside of
+ * workers as part of slicing and preview output.
+ */
+
 // dep: geo.base
 // dep: geo.polygon
 // dep: geo.polygons
@@ -407,18 +413,6 @@ function ProfiledContourGeometry(profileShape, contour, contourClosed) {
         index.push(p8, p7, p5);
     }
 
-    // unrolled / non-indexed geometry provides a cleaner look because vertex
-    // shading of indexed geometries looks wrong. this takes longer to re-compute
-    // so it should be produced unrolled above.
-    //
-    // let nufaces = new Float32Array(index.length * 3), ii = 0;
-    // for (let i of index) {
-    //     nufaces[ii++] = faces[i*3];
-    //     nufaces[ii++] = faces[i*3+1];
-    //     nufaces[ii++] = faces[i*3+2];
-    // }
-    // return { index:[], faces: nufaces };
-
     return {index, faces};
 }
 

src/kiri/render.js

@@ -2,6 +2,11 @@
 
 "use strict";
 
+/*
+ * uses `layers.js` to convert paths (usually preview) into primordial geometries.
+ * the input is based on an array (layers) of arrays containing `Output` objects
+ */
+
 // dep: geo.base
 // dep: geo.point
 // dep: geo.polygon

src/kiri/stack.js

@@ -6,6 +6,9 @@ gapp.register("kiri.stack", [], (root, exports) => {
 
 const { kiri } = root;
 
+/*
+ * converts `layers.js` output data structures into three.js meshes for display
+ */
 class Stack {
     constructor(view, freeMem, shiny) {
         this._view = view;

src/moto/space.js

@@ -403,6 +403,15 @@ gapp.register("moto.space", [], (root, exports) => {
         canvas.width = w * scale;
         canvas.height = h * scale;
 
+        canvas.addEventListener("webglcontextlost", event => {
+            console.log('WEB GL CONTEXT LOST');
+            event.preventDefault();
+        }, false);
+
+        canvas.addEventListener("webglcontextrestored", event => {
+            console.log('WEB GL CONTEXT RESTORED');
+        }, false);
+
         try {
             context.scale(scale, scale);
         } catch (e) {