Add linear easing func

1 files changed, 20 insertions, 7 deletions

diff --git a/src/_easing.scss b/src/_easing.scss
index 8bcfd39..6d66ea7 100644
--- a/src/_easing.scss
+++ b/src/_easing.scss
@@ -10,6 +10,8 @@
 ////
 
 @use 'sass:math';
+@use 'sass:map';
+@use 'sass:list';
 
 ///
 /// @access private
@@ -73,14 +75,14 @@ $cubic-bezier-subdiv-max-iters: 10 !default;
 
     $sample-pool-key: $x1 + '_' + $x2;
 
-    @if not map-has-key($cubic-bezier-sample-pool, $sample-pool-key) {
+    @if not map.has-key($cubic-bezier-sample-pool, $sample-pool-key) {
         $samples: ();
 
         @for $i from 0 through $cubic-bezier-sample-pool-size {
-            $samples: append($samples, cubic-bezier-func($x1, $x2, math.div($i, $cubic-bezier-sample-pool-size)));
+            $samples: list.append($samples, cubic-bezier-func($x1, $x2, math.div($i, $cubic-bezier-sample-pool-size)));
         }
 
-        $cubic-bezier-sample-pool: map-merge($cubic-bezier-sample-pool, ($sample-pool-key: $samples)) !global;
+        $cubic-bezier-sample-pool: map.merge($cubic-bezier-sample-pool, ($sample-pool-key: $samples)) !global;
     }
 
     //
@@ -169,7 +171,7 @@ $cubic-bezier-subdiv-max-iters: 10 !default;
             $a: $cur-t;
         }
 
-        @if abs($cur-x) < $cubic-bezier-subdiv-precision {
+        @if math.abs($cur-x) < $cubic-bezier-subdiv-precision {
             @return $cur-t;
         }
     }
@@ -184,19 +186,19 @@ $cubic-bezier-subdiv-max-iters: 10 !default;
 ///
 @function cubic-bezier-t-for-x($x1, $x2, $x) {
     $sample-pool-key: $x1 + '_' + $x2;
-    $samples:         map-get($cubic-bezier-sample-pool, $sample-pool-key);
+    $samples:         map.get($cubic-bezier-sample-pool, $sample-pool-key);
 
     $intv-start:  0;
     $cur-sample:  1;
     $last-sample: $cubic-bezier-sample-pool-size;
 
-    @while ($cur-sample != $last-sample) and (nth($samples, $cur-sample) <= $x) {
+    @while ($cur-sample != $last-sample) and (list.nth($samples, $cur-sample) <= $x) {
         $intv-start: $intv-start + math.div(1, $cubic-bezier-sample-pool-size);
         $cur-sample: $cur-sample + 1;
     }
     $cur-sample: $cur-sample - 1;
 
-    $dist:    math.div($x - nth($samples, $cur-sample), nth($samples, $cur-sample + 1) - nth($samples, $cur-sample));
+    $dist:    math.div($x - list.nth($samples, $cur-sample), list.nth($samples, $cur-sample + 1) - list.nth($samples, $cur-sample));
     $guess-t: $intv-start + math.div($dist, $cubic-bezier-sample-pool-size);
 
     $init-slope: cubic-bezier-func-slope($x1, $x2, $guess-t);
@@ -210,6 +212,17 @@ $cubic-bezier-subdiv-max-iters: 10 !default;
 }
 
 /// 
+/// Linear easing function.
+///
+/// @param {number} $x - Progress between 0 and 1 inclusive
+///
+/// @return {number}
+///
+@function linear($x) {
+    @return $x;
+}
+
+/// 
 /// Sinusoidal easing function (in direction).
 ///
 /// @param {number} $x - Progress between 0 and 1 inclusive