From 704b06ed44028b82062c74d6a673d1a45ff4c416 Mon Sep 17 00:00:00 2001
From: Daniel Imms <2193314+Tyriar@users.noreply.github.com>
Date: Wed, 17 Mar 2021 12:48:56 -0700
Subject: [PATCH] Support ballistic scroll

Fixes #227
---
 media/editor/scrollBarHandler.ts | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/media/editor/scrollBarHandler.ts b/media/editor/scrollBarHandler.ts
index c8e6a7b..6600020 100644
--- a/media/editor/scrollBarHandler.ts
+++ b/media/editor/scrollBarHandler.ts
@@ -101,10 +101,17 @@ export class ScrollBarHandler {
 		// if these are equal it means the document is too short to scroll anyways
 		if (this.scrollBarHeight === this.scrollThumbHeight) return;
 		if (event.deltaY === 0 || event.shiftKey) return;
-		if (event.deltaY > 0) {
-			this.updateVirtualScrollTop(this.scrollTop + this.rowHeight);
-		} else {
-			this.updateVirtualScrollTop(this.scrollTop - this.rowHeight);
+		switch (event.deltaMode) {
+			case WheelEvent.DOM_DELTA_LINE:
+				if (event.deltaY > 0) {
+					this.updateVirtualScrollTop(this.scrollTop + this.rowHeight);
+				} else {
+					this.updateVirtualScrollTop(this.scrollTop - this.rowHeight);
+				}
+				break;
+			case WheelEvent.DOM_DELTA_PIXEL:
+			default: // Fallback to pixel
+				this.updateVirtualScrollTop(this.scrollTop + event.deltaY);
 		}
 
 		this.updateScrolledPosition();