From 18d5182b83c46eb508d9b512b44776ecb7293d4e Mon Sep 17 00:00:00 2001
From: Luis Puig <luis@revieve.com>
Date: Thu, 26 Nov 2020 19:23:06 +0100
Subject: [PATCH 1/3] Implement relative scroll time from distance

---
 src/smoothscroll.js | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/smoothscroll.js b/src/smoothscroll.js
index 6faa8f7..ac7be27 100644
--- a/src/smoothscroll.js
+++ b/src/smoothscroll.js
@@ -16,7 +16,8 @@ function polyfill() {
 
   // globals
   var Element = w.HTMLElement || w.Element;
-  var SCROLL_TIME = 468;
+  var MIN_SCROLL_TIME = 200;
+  var MAX_SCROLL_TIME = 468;
 
   // object gathering original scroll methods
   var original = {
@@ -174,7 +175,7 @@ function polyfill() {
     var value;
     var currentX;
     var currentY;
-    var elapsed = (time - context.startTime) / SCROLL_TIME;
+    var elapsed = (time - context.startTime) / context.scrollTime;
 
     // avoid elapsed times higher than one
     elapsed = elapsed > 1 ? 1 : elapsed;
@@ -221,6 +222,12 @@ function polyfill() {
       method = scrollElement;
     }
 
+    const maxDistance = Math.max(Math.abs(x - startX), Math.abs(y - startY));
+    const scrollTime = Math.max(
+      MIN_SCROLL_TIME,
+      Math.min(MAX_SCROLL_TIME, maxDistance)
+    );
+
     // scroll looping over a frame
     step({
       scrollable: scrollable,
@@ -229,7 +236,8 @@ function polyfill() {
       startX: startX,
       startY: startY,
       x: x,
-      y: y
+      y: y,
+      scrollTime
     });
   }
 
@@ -248,14 +256,14 @@ function polyfill() {
         arguments[0].left !== undefined
           ? arguments[0].left
           : typeof arguments[0] !== 'object'
-            ? arguments[0]
-            : w.scrollX || w.pageXOffset,
+          ? arguments[0]
+          : w.scrollX || w.pageXOffset,
         // use top prop, second argument if present or fallback to scrollY
         arguments[0].top !== undefined
           ? arguments[0].top
           : arguments[1] !== undefined
-            ? arguments[1]
-            : w.scrollY || w.pageYOffset
+          ? arguments[1]
+          : w.scrollY || w.pageYOffset
       );
 
       return;

From 6d8e7e2720367603b2aaa95a01567f445ce15692 Mon Sep 17 00:00:00 2001
From: Luis Puig <luis@revieve.com>
Date: Mon, 30 Nov 2020 09:21:33 +0100
Subject: [PATCH 2/3] Improve code explinations

---
 src/smoothscroll.js | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/smoothscroll.js b/src/smoothscroll.js
index ac7be27..fd5d9dd 100644
--- a/src/smoothscroll.js
+++ b/src/smoothscroll.js
@@ -222,10 +222,17 @@ function polyfill() {
       method = scrollElement;
     }
 
-    const maxDistance = Math.max(Math.abs(x - startX), Math.abs(y - startY));
-    const scrollTime = Math.max(
+    // Calculate the maximum distance to scroll in pixels
+    const distanceToScrollX = Math.abs(x - startX);
+    const distanceToScrollY = Math.abs(y - startY);
+    const maxDistanceToScroll = Math.max(distanceToScrollX, distanceToScrollY);
+    // Configure the speed animation in pixels/ms
+    const animationSpeed = 1;
+    // Calculate the time needed for the scroll animation
+    const scrollTime =
+    Math.max(
       MIN_SCROLL_TIME,
-      Math.min(MAX_SCROLL_TIME, maxDistance)
+      Math.min(MAX_SCROLL_TIME, maxDistanceToScroll * animationSpeed)
     );
 
     // scroll looping over a frame
@@ -256,14 +263,14 @@ function polyfill() {
         arguments[0].left !== undefined
           ? arguments[0].left
           : typeof arguments[0] !== 'object'
-          ? arguments[0]
-          : w.scrollX || w.pageXOffset,
+            ? arguments[0]
+            : w.scrollX || w.pageXOffset,
         // use top prop, second argument if present or fallback to scrollY
         arguments[0].top !== undefined
           ? arguments[0].top
           : arguments[1] !== undefined
-          ? arguments[1]
-          : w.scrollY || w.pageYOffset
+            ? arguments[1]
+            : w.scrollY || w.pageYOffset
       );
 
       return;

From 26c52dbe40de9306901c21cd50c994443399671b Mon Sep 17 00:00:00 2001
From: Luis Puig <luis@revieve.com>
Date: Mon, 30 Nov 2020 09:34:01 +0100
Subject: [PATCH 3/3] Move SCROLL_SPEED to globals

---
 src/smoothscroll.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/smoothscroll.js b/src/smoothscroll.js
index fd5d9dd..603374d 100644
--- a/src/smoothscroll.js
+++ b/src/smoothscroll.js
@@ -18,6 +18,8 @@ function polyfill() {
   var Element = w.HTMLElement || w.Element;
   var MIN_SCROLL_TIME = 200;
   var MAX_SCROLL_TIME = 468;
+  // Scroll animation speed in pixels / ms
+  var SCROLL_SPEED = 1;
 
   // object gathering original scroll methods
   var original = {
@@ -226,13 +228,11 @@ function polyfill() {
     const distanceToScrollX = Math.abs(x - startX);
     const distanceToScrollY = Math.abs(y - startY);
     const maxDistanceToScroll = Math.max(distanceToScrollX, distanceToScrollY);
-    // Configure the speed animation in pixels/ms
-    const animationSpeed = 1;
     // Calculate the time needed for the scroll animation
     const scrollTime =
     Math.max(
       MIN_SCROLL_TIME,
-      Math.min(MAX_SCROLL_TIME, maxDistanceToScroll * animationSpeed)
+      Math.min(MAX_SCROLL_TIME, maxDistanceToScroll * SCROLL_SPEED)
     );
 
     // scroll looping over a frame