remove redundant handleScroll() method

handleScroll is replaced by getCurrentPage(), which effectively does the same thing.  The math is slightly different, though very similar, and result seems to be the same.

client/homebrew/brewRenderer/brewRenderer.jsx

@@ -61,12 +61,11 @@ const BrewRenderer = (props)=>{
 	};
 
 	const [state, setState] = useState({
-		viewablePageNumber : 0,
-		height             : PAGE_HEIGHT,
-		isMounted          : false,
-		visibility         : 'hidden',
-		zoom			   : 100,
-		currentPageNumber  : 1,
+		height            : PAGE_HEIGHT,
+		isMounted         : false,
+		visibility        : 'hidden',
+		zoom              : 100,
+		currentPageNumber : 1,
 	});
 
 	const mainRef  = useRef(null);
@@ -90,16 +89,6 @@ const BrewRenderer = (props)=>{
 		}));
 	};
 
-	const handleScroll = (e)=>{
-		const target = e.target;
-		setState((prevState)=>({
-			...prevState,
-			viewablePageNumber : Math.floor(target.scrollTop / target.scrollHeight * rawPages.length)
-		}));
-
-		getCurrentPage(e);
-	};
-
 	const getCurrentPage = (e) => {
 		const target = e.target;
 		const { scrollTop, clientHeight, scrollHeight } = target;
@@ -109,7 +98,7 @@ const BrewRenderer = (props)=>{
 
 		setState((prevState) => ({
 			...prevState,
-			currentPageNumber: currentPageNumber || 1
+			currentPageNumber : currentPageNumber || 1
 		}));
 	};
 
@@ -120,7 +109,7 @@ const BrewRenderer = (props)=>{
 		if(index == props.currentEditorPage)	//Already rendered before this step
 			return false;
 
-		if(Math.abs(index - state.viewablePageNumber) <= 3)
+		if(Math.abs(index - state.currentPageNumber) <= 3)
 			return true;
 
 		return false;
@@ -132,7 +121,7 @@ const BrewRenderer = (props)=>{
 				{props.renderer}
 			</div>
 			<div>
-				{state.viewablePageNumber + 1} / {rawPages.length}
+				{state.currentPageNumber} / {rawPages.length}
 			</div>
 		</div>;
 	};
@@ -219,7 +208,7 @@ const BrewRenderer = (props)=>{
 		<>
 			{/*render dummy page while iFrame is mounting.*/}
 			{!state.isMounted
-				? <div className='brewRenderer' onScroll={handleScroll}>
+				? <div className='brewRenderer' onScroll={getCurrentPage}>
 					<div className='pages'>
 						{renderDummyPage(1)}
 					</div>
@@ -242,7 +231,7 @@ const BrewRenderer = (props)=>{
 				onClick={()=>{emitClick();}}
 			>
 				<div className={'brewRenderer'}
-					onScroll={handleScroll}
+					onScroll={getCurrentPage}
 					onKeyDown={handleControlKeys}
 					tabIndex={-1}
 					style={{ height: state.height }}>