Huge performance improvements

src/js/core/buffer_maintainer.js

@@ -86,27 +86,30 @@ export class BufferMaintainer {
         // Make sure our backlog never gets too big
         clearBufferBacklog();
 
-        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",
-            ")",
+        // @ts-ignore
+        if (G_IS_DEV && false) {
+            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",
-            ")",
+                "(",
+                (bufferStats.backlogSize + "").padStart(4),
+                "backlog",
+                ")",
 
-            "VRAM:",
-            mbUsed,
-            "MB"
-        );
+                "VRAM:",
+                mbUsed,
+                "MB"
+            );
+        }
 
         ++this.iterationIndex;
     }

src/js/game/belt_path.js

@@ -175,6 +175,11 @@ export class BeltPath extends BasicSerializableObject {
      */
     onPathChanged() {
         this.acceptorTarget = this.computeAcceptingEntityAndSlot();
+
+        /**
+         * How many items past the first item are compressed
+         */
+        this.numCompressedItemsAfterFirstItem = 0;
     }
 
     /**
@@ -426,6 +431,26 @@ export class BeltPath extends BasicSerializableObject {
                 );
             }
         }
+
+        // Check first nonzero offset
+        let firstNonzero = 0;
+        for (let i = this.items.length - 2; i >= 0; --i) {
+            if (this.items[i][_nextDistance] < globalConfig.itemSpacingOnBelts + 1e-5) {
+                ++firstNonzero;
+            } else {
+                break;
+            }
+        }
+
+        // Should warn, but this check isn't actually accurate
+        // if (firstNonzero !== this.numCompressedItemsAfterFirstItem) {
+        //     console.warn(
+        //         "First nonzero index is " +
+        //             firstNonzero +
+        //             " but stored is " +
+        //             this.numCompressedItemsAfterFirstItem
+        //     );
+        // }
     }
 
     /* dev:end */
@@ -1038,11 +1063,15 @@ export class BeltPath extends BasicSerializableObject {
         // Store how much velocity (strictly its distance, not velocity) we have to distribute over all items
         let remainingVelocity = beltSpeed;
 
-        for (let i = this.items.length - 1; i >= 0; --i) {
-            const nextDistanceAndItem = this.items[i];
+        // Store the last item we processed, so we can skip clashed ones
+        let lastItemProcessed;
+
+        for (lastItemProcessed = this.items.length - 1; lastItemProcessed >= 0; --lastItemProcessed) {
+            const nextDistanceAndItem = this.items[lastItemProcessed];
 
             // Compute how much spacing we need at least
-            const minimumSpacing = i === this.items.length - 1 ? 0 : globalConfig.itemSpacingOnBelts;
+            const minimumSpacing =
+                lastItemProcessed === this.items.length - 1 ? 0 : globalConfig.itemSpacingOnBelts;
 
             // Compute how much we can advance
             const clampedProgress = Math.max(
@@ -1067,9 +1096,19 @@ export class BeltPath extends BasicSerializableObject {
                 // Try to directly get rid of the item
                 if (this.tryHandOverItem(nextDistanceAndItem[_item], excessVelocity)) {
                     this.items.pop();
+
+                    this.numCompressedItemsAfterFirstItem = Math.max(
+                        0,
+                        this.numCompressedItemsAfterFirstItem - 1
+                    );
                 }
             }
 
+            if (isFirstItemProcessed) {
+                // Skip N null items after first items
+                lastItemProcessed -= this.numCompressedItemsAfterFirstItem;
+            }
+
             isFirstItemProcessed = false;
             this.spacingToFirstItem += clampedProgress;
             if (remainingVelocity < 0.01) {
@@ -1077,11 +1116,22 @@ export class BeltPath extends BasicSerializableObject {
             }
         }
 
+        // Compute compressed item count
+        this.numCompressedItemsAfterFirstItem = Math.max(
+            0,
+            this.numCompressedItemsAfterFirstItem,
+            this.items.length - 2 - lastItemProcessed
+        );
+
         // Check if we have an item which is ready to be emitted
         const lastItem = this.items[this.items.length - 1];
         if (lastItem && lastItem[_nextDistance] === 0 && this.acceptorTarget) {
             if (this.tryHandOverItem(lastItem[_item])) {
                 this.items.pop();
+                this.numCompressedItemsAfterFirstItem = Math.max(
+                    0,
+                    this.numCompressedItemsAfterFirstItem - 1
+                );
             }
         }
 
@@ -1205,6 +1255,11 @@ export class BeltPath extends BasicSerializableObject {
                 worldPos.y + 2
             );
             progress += nextDistanceAndItem[_nextDistance];
+
+            if (this.items.length - 1 - this.numCompressedItemsAfterFirstItem === i) {
+                parameters.context.fillStyle = "red";
+                parameters.context.fillRect(worldPos.x + 5, worldPos.y, 20, 3);
+            }
         }
 
         for (let i = 0; i < this.entityPath.length; ++i) {