From 2766bf15d487497127006e701db5e13f022f2b17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20Zag=C3=B3rski?= <zbigniew@cartodb.com>
Date: Fri, 18 Oct 2024 14:16:55 +0200
Subject: [PATCH] carto: RasterLayer fix perf issue caused by spurious data
 changes

---
 modules/carto/src/layers/raster-layer.ts | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/modules/carto/src/layers/raster-layer.ts b/modules/carto/src/layers/raster-layer.ts
index 6d529a19455..074dd4987da 100644
--- a/modules/carto/src/layers/raster-layer.ts
+++ b/modules/carto/src/layers/raster-layer.ts
@@ -81,6 +81,15 @@ type _RasterLayerProps = {
   tileIndex: bigint;
 };
 
+type RasterColumnLayerData = {
+  data: Raster;
+  length: number;
+};
+
+function wrappedDataComparator(oldData: RasterColumnLayerData, newData: RasterColumnLayerData) {
+  return oldData.data === newData.data && oldData.length === newData.length;
+}
+
 // Adapter layer around RasterColumnLayer that converts data & accessors into correct format
 export default class RasterLayer<DataT = any, ExtraProps = {}> extends CompositeLayer<
   Required<RasterLayerProps<DataT>> & ExtraProps
@@ -130,6 +139,7 @@ export default class RasterLayer<DataT = any, ExtraProps = {}> extends Composite
           data, // Pass through data for getSubLayerAccessor()
           length: blockSize * blockSize
         },
+        dataComparator: wrappedDataComparator,
         offset,
         lineWidthScale, // Re-use widthScale prop to pass cell scale,
         highlightedObjectIndex,