Line area overlay

addons/tau-plot/plot/plot.gd

@@ -11,10 +11,12 @@ const PaneOverlayType = preload("res://addons/tau-plot/plot/xy/pane_overlay_type
 const VisualAttributes = preload("res://addons/tau-plot/plot/xy/visual_attributes.gd").VisualAttributes
 const BarVisualAttributes := preload("res://addons/tau-plot/plot/xy/bar/bar_visual_attributes.gd").BarVisualAttributes
 const ScatterVisualAttributes = preload("res://addons/tau-plot/plot/xy/scatter/scatter_visual_attributes.gd").ScatterVisualAttributes
+const LineVisualAttributes = preload("res://addons/tau-plot/plot/xy/line/line_visual_attributes.gd").LineVisualAttributes
 
 const VisualCallbacks = preload("res://addons/tau-plot/plot/xy/visual_callbacks.gd").VisualCallbacks
 const BarVisualCallbacks := preload("res://addons/tau-plot/plot/xy/bar/bar_visual_callbacks.gd").BarVisualCallbacks
 const ScatterVisualCallbacks = preload("res://addons/tau-plot/plot/xy/scatter/scatter_visual_callbacks.gd").ScatterVisualCallbacks
+const LineVisualCallbacks = preload("res://addons/tau-plot/plot/xy/line/line_visual_callbacks.gd").LineVisualCallbacks
 
 const SampleHit = preload("res://addons/tau-plot/plot/xy/hover/sample_hit.gd").SampleHit
 

addons/tau-plot/plot/xy/bar/bar_config.gd

@@ -24,6 +24,17 @@ enum BarMode
 const StackedNormalization = preload("res://addons/tau-plot/plot/xy/stacked_normalization.gd").StackedNormalization
 @export var stacked_normalization: StackedNormalization = StackedNormalization.NONE
 
+const StackedNegativePolicy = preload("res://addons/tau-plot/plot/xy/stacked_negative_policy.gd").StackedNegativePolicy
+
+## How negative values are handled in STACKED mode:
+## - SKIP_NEGATIVES (default) drops negative samples entirely from the stack.
+## - DIVERGING splits each X into an upper stack of positive values and
+## a lower stack of negative values, both anchored at zero.
+## - SIGNED_SUM is not a valid choice for bars: bar geometry cannot represent a
+## downward dip without overlapping rectangles. Setting it produces a validation
+## error.
+@export var stacked_negative_policy: StackedNegativePolicy = StackedNegativePolicy.SKIP_NEGATIVES
+
 
 enum BarWidthPolicy
 {
@@ -150,6 +161,8 @@ func is_equal_to(p_other: TauPaneOverlayConfig) -> bool:
 		return false
 	if stacked_normalization != other.stacked_normalization:
 		return false
+	if stacked_negative_policy != other.stacked_negative_policy:
+		return false
 
 	if bar_width_policy != other.bar_width_policy:
 		return false
@@ -180,10 +193,11 @@ func is_equal_to(p_other: TauPaneOverlayConfig) -> bool:
 # Returns true if the change between this and p_other affects layout/domain.
 # Returns false if the change only affects visual appearance.
 #
-# Only mode and stacked_normalization affect the domain (stacking changes Y
-# bounds via _apply_bar_domain_overrides_y). All width, gap, and spacing
-# properties are visual-only: they control how bars are drawn within a fixed
-# domain but do not feed into domain or tick computation.
+# mode, stacked_normalization, and stacked_negative_policy affect the domain:
+# stacking changes Y bounds, normalization pins the range, and the negative
+# policy decides whether the lower half-axis exists. All width, gap, and
+# spacing properties are visual-only: they control how bars are drawn within
+# a fixed domain but do not feed into domain or tick computation.
 func has_layout_affecting_change(p_other: TauPaneOverlayConfig) -> bool:
 	var other := p_other as TauBarConfig
 	if other == null:
@@ -198,4 +212,7 @@ func has_layout_affecting_change(p_other: TauPaneOverlayConfig) -> bool:
 	if mode == BarMode.STACKED and stacked_normalization != other.stacked_normalization:
 		return true
 
+	if mode == BarMode.STACKED and stacked_negative_policy != other.stacked_negative_policy:
+		return true
+
 	return false

addons/tau-plot/plot/xy/bar/bar_hit_record.gd

@@ -9,9 +9,14 @@ class BarHitRecord extends RefCounted:
 	## Float for continuous x, String for categorical.
 	var x_value: Variant
 
-	## Plotted y value. For STACKED with normalization, this is the scaled
-	## value matching the y-axis labels, not the raw dataset value.
-	var y_value: float
+	## Y position the bar's top is drawn at, in axis units.
+	## Differs from y_raw_value when STACKED is on (cumulative top) or when
+	## FRACTION/PERCENT normalization is on.
+	var y_plotted_value: float
+
+	## Original dataset value, before any stacking, normalization, or
+	## accumulation. Equal to y_plotted_value when STACKED is off.
+	var y_raw_value: float
 
 	## Painted rectangle, clipped to the pane.
 	var rect: Rect2

addons/tau-plot/plot/xy/bar/bar_hit_tester.gd

@@ -35,7 +35,7 @@ class BarHitTester extends OverlayHitTester:
 		return _bar_config.hoverable
 
 
-	func get_preferred_hover_mode() -> int:
+	func get_preferred_hover_mode() -> HoverMode:
 		return HoverMode.X_ALIGNED
 
 
@@ -80,14 +80,12 @@ class BarHitTester extends OverlayHitTester:
 		if _layout.domain.config.x_axis.type == TauAxisConfig.Type.CATEGORICAL:
 			return {}
 
-		# TODO: drop x_is_horizontal once XYLayout exposes a logical-x projector.
-		var x_is_horizontal: bool = _layout._x_is_horizontal
 		var best_px := INF
 		var best_val: float = 0.0
 		var found := false
 
 		for record: BarHitRecord in _bar_renderer.get_hit_records():
-			var anchor_along_x: float = record.anchor.x if x_is_horizontal else record.anchor.y
+			var anchor_along_x: float = _layout.map_screen_to_point(record.anchor).x
 			if absf(p_along_x_px - anchor_along_x) < absf(p_along_x_px - best_px):
 				best_px = anchor_along_x
 				best_val = record.x_value
@@ -108,7 +106,8 @@ class BarHitTester extends OverlayHitTester:
 		hit.series_name = _dataset.get_series_name(p_record.series_id)
 		hit.sample_index = p_record.sample_index
 		hit.x_value = p_record.x_value
-		hit.y_value = p_record.y_value
+		hit.y_plotted_value = p_record.y_plotted_value
+		hit.y_raw_value = p_record.y_raw_value
 		hit.screen_position = p_record.anchor
 		hit.pane_index = _pane_index
 		hit.overlay_type = PaneOverlayType.BAR