Minor "buffers" cleanup

Remove the canvas context loss handling as it was incorrect, simplify
the error conditions in makeOffscreenBuffer and remove commented out
code.

src/js/core/buffer_maintainer.js

@@ -1,7 +1,6 @@
 import { GameRoot } from "../game/root";
-import { clearBufferBacklog, freeCanvas, getBufferStats, makeOffscreenBuffer } from "./buffer_utils";
+import { clearBufferBacklog, freeCanvas, makeOffscreenBuffer } from "./buffer_utils";
 import { createLogger } from "./logging";
-import { round1Digit } from "./utils";
 
 /**
  * @typedef {{
@@ -35,7 +34,7 @@ export class BufferMaintainer {
      * Returns the buffer stats
      */
     getStats() {
-        let stats = {
+        const stats = {
             rootKeys: 0,
             subKeys: 0,
             vramBytes: 0,
@@ -59,25 +58,16 @@ export class BufferMaintainer {
      * for a few iterations
      */
     garbargeCollect() {
-        let totalKeys = 0;
-        let deletedKeys = 0;
         const minIteration = this.iterationIndex;
 
         this.cache.forEach((subCache, key) => {
-            let unusedSubKeys = [];
+            const unusedSubKeys = [];
 
             // Filter sub cache
             subCache.forEach((cacheEntry, subKey) => {
-                if (
-                    cacheEntry.lastUse < minIteration ||
-                    // @ts-ignore
-                    cacheEntry.canvas._contextLost
-                ) {
+                if (cacheEntry.lastUse < minIteration) {
                     unusedSubKeys.push(subKey);
                     freeCanvas(cacheEntry.canvas);
-                    ++deletedKeys;
-                } else {
-                    ++totalKeys;
                 }
             });
 
@@ -90,30 +80,6 @@ export class BufferMaintainer {
         // Make sure our backlog never gets too big
         clearBufferBacklog();
 
-        // if (G_IS_DEV) {
-        //     const bufferStats = getBufferStats();
-        //     const mbUsed = round1Digit(bufferStats.vramUsage / (1024 * 1024));
-        //     logger.log(
-        //         "GC: Remove",
-        //         (deletedKeys + "").padStart(4),
-        //         ", Remain",
-        //         (totalKeys + "").padStart(4),
-        //         "(",
-        //         (bufferStats.bufferCount + "").padStart(4),
-        //         "total",
-        //         ")",
-
-        //         "(",
-        //         (bufferStats.backlogSize + "").padStart(4),
-        //         "backlog",
-        //         ")",
-
-        //         "VRAM:",
-        //         mbUsed,
-        //         "MB"
-        //     );
-        // }
-
         ++this.iterationIndex;
     }
 
@@ -180,7 +146,7 @@ export class BufferMaintainer {
      *
      */
     getForKeyOrNullNoUpdate({ key, subKey }) {
-        let parent = this.cache.get(key);
+        const parent = this.cache.get(key);
         if (!parent) {
             return null;
         }

src/js/core/buffer_utils.js

@@ -82,15 +82,7 @@ export function clearBufferBacklog() {
  * @returns {[HTMLCanvasElement, CanvasRenderingContext2D]}
  */
 export function makeOffscreenBuffer(w, h, { smooth = true, reusable = true, label = "buffer" }) {
-    assert(w > 0 && h > 0, "W or H < 0");
-    if (w % 1 !== 0 || h % 1 !== 0) {
-        // console.warn("Subpixel offscreen buffer size:", w, h);
-    }
-    if (w < 1 || h < 1) {
-        logger.error("Offscreen buffer size < 0:", w, "x", h);
-        w = Math.max(1, w);
-        h = Math.max(1, h);
-    }
+    assert(w >= 1 && h >= 1, "Invalid offscreen buffer size: W or H < 1");
 
     const recommendedSize = 1024 * 1024;
     if (w * h > recommendedSize) {
@@ -140,20 +132,7 @@ export function makeOffscreenBuffer(w, h, { smooth = true, reusable = true, labe
 
         // Initial state
         context.save();
-
-        canvas.addEventListener("webglcontextlost", () => {
-            console.warn("canvas::webglcontextlost", canvas);
-            // @ts-ignore
-            canvas._contextLost = true;
-        });
-        canvas.addEventListener("contextlost", () => {
-            console.warn("canvas::contextlost", canvas);
-            // @ts-ignore
-            canvas._contextLost = true;
-        });
     }
-    // @ts-ignore
-    canvas._contextLost = false;
 
     // @ts-ignore
     canvas.label = label;

src/js/game/map_view.js

@@ -1,11 +1,11 @@
+import { freeCanvas, makeOffscreenBuffer } from "../core/buffer_utils";
 import { globalConfig } from "../core/config";
 import { DrawParameters } from "../core/draw_parameters";
-import { BaseMap } from "./map";
-import { freeCanvas, makeOffscreenBuffer } from "../core/buffer_utils";
 import { Entity } from "./entity";
-import { THEME } from "./theme";
-import { MapChunkView } from "./map_chunk_view";
+import { BaseMap } from "./map";
 import { MapChunkAggregate } from "./map_chunk_aggregate";
+import { MapChunkView } from "./map_chunk_view";
+import { THEME } from "./theme";
 
 /**
  * This is the view of the map, it extends the map which is the raw model and allows
@@ -241,12 +241,6 @@ export class MapView extends BaseMap {
                 key = "placing";
             }
 
-            // @ts-ignore`
-            if (this.cachedBackgroundCanvases[key]._contextLost) {
-                freeCanvas(this.cachedBackgroundCanvases[key]);
-                this.internalInitializeCachedBackgroundCanvases();
-            }
-
             parameters.context.fillStyle = parameters.context.createPattern(
                 this.cachedBackgroundCanvases[key],
                 "repeat"