1 files changed, 19 insertions, 10 deletions

diff --git a/src/Utils.ts b/src/Utils.ts
index 5e0514bc6..9d3b9eb2b 100644
--- a/src/Utils.ts
+++ b/src/Utils.ts
@@ -558,9 +558,13 @@ export namespace JSONUtils {
     }
 }
 
-const easeInOutQuad = (currentTime: number, start: number, change: number, duration: number) => {
-    let newCurrentTime = currentTime / (duration / 2);
+const easeFunc = (transition: 'ease' | 'linear' | undefined, currentTime: number, start: number, change: number, duration: number) => {
+    if (transition === 'linear') {
+        let newCurrentTime = currentTime / duration; //  currentTime / (duration / 2);
+        return start + newCurrentTime * change;
+    }
 
+    let newCurrentTime = currentTime / (duration / 2);
     if (newCurrentTime < 1) {
         return (change / 2) * newCurrentTime * newCurrentTime + start;
     }
@@ -569,23 +573,28 @@ const easeInOutQuad = (currentTime: number, start: number, change: number, durat
     return (-change / 2) * (newCurrentTime * (newCurrentTime - 2) - 1) + start;
 };
 
-export function smoothScroll(duration: number, element: HTMLElement | HTMLElement[], to: number) {
+export function smoothScroll(duration: number, element: HTMLElement | HTMLElement[], to: number, transition: 'ease' | 'linear' | undefined, stopper?: () => void) {
+    stopper?.();
     const elements = element instanceof HTMLElement ? [element] : element;
     const starts = elements.map(element => element.scrollTop);
     const startDate = new Date().getTime();
-
+    let _stop = false;
+    const stop = () => (_stop = true);
     const animateScroll = () => {
         const currentDate = new Date().getTime();
         const currentTime = currentDate - startDate;
-        elements.map((element, i) => (element.scrollTop = easeInOutQuad(currentTime, starts[i], to - starts[i], duration)));
+        elements.map((element, i) => (element.scrollTop = easeFunc(transition, currentTime, starts[i], to - starts[i], duration)));
 
-        if (currentTime < duration) {
-            requestAnimationFrame(animateScroll);
-        } else {
-            elements.forEach(element => (element.scrollTop = to));
+        if (!_stop) {
+            if (currentTime < duration) {
+                requestAnimationFrame(animateScroll);
+            } else {
+                elements.forEach(element => (element.scrollTop = to));
+            }
         }
     };
     animateScroll();
+    return stop;
 }
 
 export function smoothScrollHorizontal(duration: number, element: HTMLElement | HTMLElement[], to: number) {
@@ -596,7 +605,7 @@ export function smoothScrollHorizontal(duration: number, element: HTMLElement |
     const animateScroll = () => {
         const currentDate = new Date().getTime();
         const currentTime = currentDate - startDate;
-        elements.map((element, i) => (element.scrollLeft = easeInOutQuad(currentTime, starts[i], to - starts[i], duration)));
+        elements.map((element, i) => (element.scrollLeft = easeFunc('ease', currentTime, starts[i], to - starts[i], duration)));
 
         if (currentTime < duration) {
             requestAnimationFrame(animateScroll);