From d3a9bf375c6c99cea7c99273911ece8adfd9f655 Mon Sep 17 00:00:00 2001
From: Evert Timberg <evert.timberg@gmail.com>
Date: Mon, 21 Feb 2022 08:33:33 -0500
Subject: [PATCH] Allow individual chart controllers to opt-in to the
 decimation plugin (#10182)

* Allow individual chart controllers to opt-in to the decimation plugin

* Code review feedback
---
 src/controllers/controller.line.js | 1 +
 src/core/core.datasetController.js | 1 +
 src/plugins/plugin.decimation.js   | 2 +-
 types/index.esm.d.ts               | 4 ++++
 4 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/controllers/controller.line.js b/src/controllers/controller.line.js
index a62d9be89..be96e72ed 100644
--- a/src/controllers/controller.line.js
+++ b/src/controllers/controller.line.js
@@ -7,6 +7,7 @@ export default class LineController extends DatasetController {
 
   initialize() {
     this.enableOptionSharing = true;
+    this.supportsDecimation = true;
     super.initialize();
   }
 
diff --git a/src/core/core.datasetController.js b/src/core/core.datasetController.js
index b6c6778d9..85cc50e91 100644
--- a/src/core/core.datasetController.js
+++ b/src/core/core.datasetController.js
@@ -237,6 +237,7 @@ export default class DatasetController {
     this._drawStart = undefined;
     this._drawCount = undefined;
     this.enableOptionSharing = false;
+    this.supportsDecimation = false;
     this.$context = undefined;
     this._syncList = [];
 
diff --git a/src/plugins/plugin.decimation.js b/src/plugins/plugin.decimation.js
index 20fbb44b9..95604e429 100644
--- a/src/plugins/plugin.decimation.js
+++ b/src/plugins/plugin.decimation.js
@@ -217,7 +217,7 @@ export default {
         return;
       }
 
-      if (meta.type !== 'line') {
+      if (!meta.controller.supportsDecimation) {
         // Only line datasets are supported
         return;
       }
diff --git a/types/index.esm.d.ts b/types/index.esm.d.ts
index ace3a249f..882a8df47 100644
--- a/types/index.esm.d.ts
+++ b/types/index.esm.d.ts
@@ -578,6 +578,10 @@ export class DatasetController<
   readonly index: number;
   readonly _cachedMeta: ChartMeta<TElement, TDatasetElement, TType>;
   enableOptionSharing: boolean;
+  // If true, the controller supports the decimation
+  // plugin. Defaults to `false` for all controllers
+  // except the LineController
+  supportsDecimation: boolean;
 
   linkScales(): void;
   getAllParsedValues(scale: Scale): number[];
-- 
2.47.2