Use int+float to store picker value to fix rounding errors.

1 files changed, 34 insertions, 48 deletions

diff --git a/date_picker/scroll_picker.gd b/date_picker/scroll_picker.gd
index afbb02e..4ae22c0 100644
--- a/date_picker/scroll_picker.gd
+++ b/date_picker/scroll_picker.gd
@@ -4,25 +4,17 @@ const VELOCITY_DECAYING_FACTOR: float = 5.5
 const BINNING_THRESHOLD: float = 0.75
 const BINNING_ADJUST_P: float = 5.0
 
-export var min_value: int setget set_min_value
-export var max_value: int setget set_max_value
-var num_of_values: int
-
-func set_min_value(value: int):
-	min_value = value
-	num_of_values = max_value - min_value + 1
-
-func set_max_value(value: int):
-	max_value = value
-	num_of_values = max_value - min_value + 1
+export var min_value: int
+export var max_value: int
 
 var pointer: Dictionary
-var value: float = 0.0 # @DAM TODO Maybe rename variable?
-var anchor: float = 0.0
+var anchor: float
+var value: int
+var offset: float
 
 var current_value_base_position: float
-var next_value_base_position: float
 var previous_value_base_position: float
+var next_value_base_position: float
 
 
 func _ready():
@@ -32,66 +24,60 @@ func _ready():
 		current_position = Vector2.ZERO,
 		velocity = Vector2.ZERO,
 		is_active = false,
-		}
+	}
 	current_value_base_position = ($value as Label).rect_position.y
-	next_value_base_position = ($value_next as Label).rect_position.y
 	previous_value_base_position = ($value_previous as Label).rect_position.y
+	next_value_base_position = ($value_next as Label).rect_position.y
+	value = min_value
+	offset = 0.0
 
 
 func _process(delta: float):
 	
+	# @DAM Review variable name, and maybe move it elsewhere.
 	var scroll_unit_height := ($value as Label).rect_size.y
-	var normalized_value := value / scroll_unit_height
-	var normalized_int_value := round(normalized_value) as int
-	
-	var normalized_displacement := normalized_value - normalized_int_value
-	var displacement := normalized_displacement * scroll_unit_height
 	
 	if pointer.is_active:
-		value = anchor - (pointer.current_position.y - pointer.initial_position.y)
+		var dragged_distance: float = - (pointer.current_position.y - pointer.initial_position.y)
+		offset = anchor + (dragged_distance / scroll_unit_height)
+		value = int(offset)
+		offset -= value
 	else:
 		pointer.velocity *= clamp((1.0 - VELOCITY_DECAYING_FACTOR * delta), 0.0, 1.0)
-		value -= pointer.velocity.y * delta
-		if abs(pointer.velocity.y) < BINNING_THRESHOLD * scroll_unit_height && abs(displacement) > 0.5:
-			pointer.velocity.y = 0.0
-			value -= displacement * BINNING_ADJUST_P * delta
+		offset -= pointer.velocity.y * delta / scroll_unit_height
+		if abs(pointer.velocity.y) < BINNING_THRESHOLD * scroll_unit_height:
+			offset -= offset * BINNING_ADJUST_P * delta
 	
-	var logic_value := min_value + fposmod(normalized_int_value, num_of_values)
-	var logic_next_value := min_value + fposmod(normalized_int_value + 1, num_of_values)
-	var logic_previous_value := min_value + fposmod(normalized_int_value - 1, num_of_values)
+	# Using 'offset * 2.0' (equivalent to 'offset / 0.5') rounds the value based on 0.5 units.
+	var cummulative_displacement := int(offset * 2.0)
+	value = wrapi(value + cummulative_displacement, min_value, max_value + 1)
+	offset -= cummulative_displacement
 	
 	# @DAM TODO Change all '$access' with variables set during on '_ready'.
-	$value.text = "%d" % logic_value
-	$value_next.text = "%d" % logic_next_value
-	$value_previous.text = "%d" % logic_previous_value
-	
-	($value as Label).rect_position.y = current_value_base_position - displacement
-	($value_previous as Label).rect_position.y = previous_value_base_position - displacement
-	($value_next as Label).rect_position.y = next_value_base_position - displacement
+	$value.text = "%d" % value
+	$value_next.text = "%d" % wrapi(value + 1, min_value, max_value + 1)
+	$value_previous.text = "%d" % wrapi(value - 1, min_value, max_value + 1)
 	
-	($value_next as Label).modulate.a = normalized_displacement + 0.5
-	($value_previous as Label).modulate.a = 0.5 - normalized_displacement
+	var offset_position := offset * scroll_unit_height
+	($value as Label).rect_position.y = current_value_base_position - offset_position
+	($value_previous as Label).rect_position.y = previous_value_base_position - offset_position
+	($value_next as Label).rect_position.y = next_value_base_position - offset_position
 	
-	# @DAM TODO Rename these variables.
-	var current_pos := value
-	var turn_over := num_of_values * scroll_unit_height
-	if current_pos >= turn_over || current_pos < 0.0:
-		value = fposmod(current_pos, turn_over)
+	($value_previous as Label).modulate.a = 0.5 - offset
+	($value_next as Label).modulate.a = offset + 0.5
 
 
 func _gui_input(event: InputEvent):
 	
-	# @DAM TODO When we release the pointer, we will receive an event that will se the 'current_position' as the last 'touch.position'.
-	if event is InputEventScreenTouch:
-#	if (event is InputEventScreenTouch && pointer.is_active && pointer.index == event.index
-#	|| event is InputEventScreenTouch && pointer.is_active == false):
+	# @DAM TODO TEST
+	if event is InputEventScreenTouch && (pointer.is_active == false || pointer.index == event.index):
 		var touch := event as InputEventScreenTouch
 		pointer.is_active = event.pressed
 		pointer.current_position = touch.position
 		if pointer.is_active:
 			pointer.index = touch.index
 			pointer.initial_position = touch.position
-			anchor = value
+			anchor = value + offset
 		else:
 			pointer.index = -1