Scroll up/down when tapping top/bottom quarters of webtoon viewer

Includes a fix from J2K: https://github.com/Jays2Kings/tachiyomiJ2K/commit/4e45a337dab08a0fedd3a4b8a5482c221a95956f

app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerViewer.kt

@@ -82,8 +82,8 @@ abstract class PagerViewer(val activity: ReaderActivity) : BaseViewer {
         pager.tapListener = { event ->
             val positionX = event.x
             when {
-                positionX < pager.width * 0.33f -> if (config.tappingEnabled) moveLeft() else activity.toggleMenu()
-                positionX > pager.width * 0.66f -> if (config.tappingEnabled) moveRight() else activity.toggleMenu()
+                positionX < pager.width * 0.33f && config.tappingEnabled -> moveLeft()
+                positionX > pager.width * 0.66f && config.tappingEnabled -> moveRight()
                 else -> activity.toggleMenu()
             }
         }

app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/webtoon/WebtoonViewer.kt

@@ -94,9 +94,12 @@ class WebtoonViewer(val activity: ReaderActivity, val isContinuous: Boolean = tr
         })
         recycler.tapListener = { event ->
             val positionX = event.rawX
+            val positionY = event.rawY
             when {
-                positionX < recycler.width * 0.33 -> if (config.tappingEnabled) scrollUp() else activity.toggleMenu()
-                positionX > recycler.width * 0.66 -> if (config.tappingEnabled) scrollDown() else activity.toggleMenu()
+                positionY < recycler.height * 0.25 && config.tappingEnabled -> scrollUp()
+                positionY > recycler.height * 0.75 && config.tappingEnabled -> scrollDown()
+                positionX < recycler.width * 0.33 && config.tappingEnabled -> scrollUp()
+                positionX > recycler.width * 0.66 && config.tappingEnabled -> scrollDown()
                 else -> activity.toggleMenu()
             }
         }