Fix for edge cases

README.md

@@ -60,8 +60,9 @@ update_frequency = 60
 -- Tween function can be a string, a predefined easing function, or a custom easing function
 local tween_function = "linear" or tweener.linear or go.EASING_LINEAR or gui.EASING_LINEAR or {0, 0.2, 0.4, 0.8, 0.9, 1}
 
-tweener.tween(tween_function, from, to, time, callback, [dt])
 tweener.ease(tween_function, from, to, time, time_elapsed)
+tweener.tween(tween_function, from, to, time, callback, [dt]) -- Returns tween_id
+tweener.cancel(tween_id)
 ```
 
 ### Importing the Module

game.project

@@ -1,5 +1,5 @@
 [bootstrap]
-main_collection = /example/example.collectionc
+main_collection = /test/test.collectionc
 
 [script]
 shared_state = 1

test/test_tweener.lua

@@ -31,6 +31,13 @@ return function()
 			assert(tweener.ease(easing, 0, 100, 1, -1) == 0)
 			assert(tweener.ease(easing, 0, 100, 1, 0) == 0)
 			assert(tweener.ease(easing, 0, 100, 1, 2) == 0)
+
+			-- Non from zero
+			assert(tweener.ease(easing, 100, 200, 1, 0) == 100)
+			assert(tweener.ease(easing, 100, 200, 1, 0.25) == 200)
+			assert(tweener.ease(easing, 100, 200, 1, 0.5) == 300)
+			assert(tweener.ease(easing, 100, 200, 1, 0.75) == 200)
+			assert(tweener.ease(easing, 100, 200, 1, 1) == 100)
 		end)
 
 		it("Tweener should support each Defold tweening", function()

tweener/tweener.lua

@@ -112,10 +112,10 @@ function M.custom_ease(easing, t, b, c, d)
 
 	local time_progress = t / d
 	if time_progress >= 1 then
-		return (c + b) * easing[sample_count]
+		return c * easing[sample_count] + b
 	end
 	if time_progress <= 0 then
-		return b * easing[1]
+		return b + (c * easing[1])
 	end
 
 	local sample_index = sample_count - 1