Native forms: share geometry and paint owners without a styles mirror

src/textual/_arrange.py

@@ -30,8 +30,8 @@ def _build_layers(widgets: Iterable[Widget]) -> Mapping[str, Sequence[Widget]]:
     return layers
 
 
-_get_dock = attrgetter("styles.is_docked")
-_get_split = attrgetter("styles.is_split")
+_get_dock = attrgetter("geometry.is_docked")
+_get_split = attrgetter("geometry.is_split")
 _get_display = attrgetter("display")
 
 
@@ -54,7 +54,7 @@ def arrange(
     """
     placements: list[WidgetPlacement] = []
     scroll_spacing = NULL_SPACING
-    styles = widget.styles
+    styles = widget.geometry
 
     # Widgets which will be displayed
     display_widgets = list(filter(_get_display, children))
@@ -149,7 +149,7 @@ def _arrange_dock_widgets(
     append_placement = placements.append
 
     for dock_widget in dock_widgets:
-        edge = dock_widget.styles.dock
+        edge = dock_widget.geometry.dock
 
         box_model = dock_widget._get_box_model(
             size, viewport, size.width, size.height, greedy=greedy
@@ -175,15 +175,7 @@ def _arrange_dock_widgets(
             raise AssertionError("invalid value for dock edge")  # pragma: no-cover
 
         dock_region = dock_region.shrink(margin)
-        styles = dock_widget.styles
-        offset = (
-            styles.offset.resolve(
-                size,
-                viewport,
-            )
-            if styles.has_rule("offset")
-            else NULL_OFFSET
-        )
+        offset = dock_widget.geometry.resolve_offset(size, viewport)
         append_placement(
             _WidgetPlacement(
                 dock_region.translate(region_offset),
@@ -223,7 +215,7 @@ def _arrange_split_widgets(
     null_offset = NULL_OFFSET
 
     for split_widget in split_widgets:
-        split = split_widget.styles.split
+        split = split_widget.geometry.split
         box_model = split_widget._get_box_model(
             size, viewport, size.width, size.height
         )

src/textual/_compositor.py

@@ -45,6 +45,7 @@
 from textual._activation import Activation
 from textual._loop import loop_last
 from textual._spatial_map import SpatialMap
+from textual.box_model import DEFAULT_LAYER
 from textual.geometry import NULL_OFFSET, NULL_SPACING, Offset, Region, Size, Spacing
 from textual.map_geometry import MapGeometry
 from textual.layout import WidgetPlacement
@@ -1288,7 +1289,7 @@ def store_geometry(node: Widget, geometry: MapGeometry, clip: SceneClip) -> None
             None if root_layers is None
             else {name: index for index, name in enumerate(root_layers)}
         )
-        default_layers = {"default": 0}
+        default_layers = {DEFAULT_LAYER: 0}
         retained_paths: set[Widget] = set()
         if visible_only:
             # Requested targets need their outer placement even when offscreen.
@@ -1347,7 +1348,7 @@ def arrange_widget(
                 invisible_widgets.add(widget)
 
             # Container region is minus border
-            container_region = region.shrink(styles.gutter)
+            container_region = region.shrink(widget.geometry.box_gutter)
             container_size = container_region.size
 
             # Widgets with scrollbars (containers or scroll view) require additional processing
@@ -1416,7 +1417,7 @@ def arrange_widget(
                     if widget._cover_widget is not None:
                         store_geometry(widget._cover_widget, _MapGeometry.from_widget(
                             widget._cover_widget,
-                            region.shrink(widget.styles.gutter),
+                            region.shrink(widget.geometry.box_gutter),
                             order,
                             clip.region,
                             region.size,
@@ -1461,7 +1462,7 @@ def arrange_widget(
                     if (
                         widget.show_vertical_scrollbar
                         or widget.show_horizontal_scrollbar
-                    ) and styles.scrollbar_visibility == "visible":
+                    ) and widget.geometry.scrollbar_visibility == "visible":
                         for chrome_widget, chrome_region in widget._arrange_scrollbars(
                             container_region
                         ):

src/textual/_extrema.py

@@ -1,14 +1,10 @@
 from __future__ import annotations
 
 from fractions import Fraction
-from typing import TYPE_CHECKING, NamedTuple
+from typing import NamedTuple
 
 from textual.geometry import Size
 
-if TYPE_CHECKING:
-    from textual.css.styles import StylesBase
-
-
 class Extrema(NamedTuple):
     """Specifies minimum and maximum dimensions."""
 
@@ -66,56 +62,5 @@ def apply_dimensions(self, width: int, height: int) -> Size:
             int(self.apply_height(height)),
         )
 
-    @classmethod
-    def resolve(
-        cls, styles: StylesBase, container: Size, viewport: Size,
-        width_fraction: Fraction, height_fraction: Fraction,
-    ) -> Extrema:
-        """Resolve native min/max rules independently of scene custody."""
-        min_width_rule = styles.min_width
-        max_width_rule = styles.max_width
-        min_height_rule = styles.min_height
-        max_height_rule = styles.max_height
-        if (min_width_rule is None and max_width_rule is None
-                and min_height_rule is None and max_height_rule is None):
-            return NO_EXTREMA
-
-        min_width: Fraction | int | None = None
-        max_width: Fraction | int | None = None
-        min_height: Fraction | int | None = None
-        max_height: Fraction | int | None = None
-
-        container -= styles.margin.totals
-        if styles.box_sizing == "border-box":
-            gutter_width, gutter_height = styles.gutter.totals
-        else:
-            gutter_width = gutter_height = 0
-
-        if min_width_rule is not None:
-            min_width = (
-                min_width_rule.resolve(container, viewport, width_fraction)
-                - gutter_width
-            )
-
-        if max_width_rule is not None:
-            max_width = (
-                max_width_rule.resolve(container, viewport, width_fraction)
-                - gutter_width
-            )
-        if min_height_rule is not None:
-            min_height = (
-                min_height_rule.resolve(container, viewport, height_fraction)
-                - gutter_height
-            )
-
-        if max_height_rule is not None:
-            max_height = (
-                max_height_rule.resolve(container, viewport, height_fraction)
-                - gutter_height
-            )
-
-        return cls(min_width, max_width, min_height, max_height)
-
-
 NO_EXTREMA = Extrema()
 """Extrema of a node with no min or max rules."""

src/textual/_measurement.py

@@ -160,12 +160,12 @@ def styles_sensitive(self, widget: Widget) -> bool:
         )
 
     def depends(self, widget: Widget, *, greedy: bool = True) -> bool:
-        styles = widget.styles
+        styles = widget.geometry
         if (not widget._native_measurement_layout_hooks
                 or styles.align_horizontal != "left" or styles.align_vertical != "top"):
             return True
         for child in widget.displayed_children:
-            child_styles = child.styles
+            child_styles = child.geometry
             if child_styles.is_docked or child_styles.is_split or child_styles.overlay == "screen":
                 return True
             # Match native auto-parent stretch semantics, which treat all
@@ -204,7 +204,7 @@ class GridHeight(FlowHeight):
     box_depends = HeightDependency.box_depends
 
     def depends(self, widget: Widget, *, greedy: bool = True) -> bool:
-        styles = widget.styles
+        styles = widget.geometry
         rows, columns = styles.grid_rows or (), styles.grid_columns or ()
         # Default rows become fractional at nonzero height for non-auto parents.
         if (not rows and not styles.is_auto_height
@@ -214,7 +214,7 @@ def depends(self, widget: Widget, *, greedy: bool = True) -> bool:
         auto_rows = not rows or any(row.is_auto for row in rows)
         auto_columns = any(column.is_auto for column in columns)
         for child in widget.displayed_children:
-            child_styles = child.styles
+            child_styles = child.geometry
             # Auto cells pass the outer size directly to content measurement
             # and extrema. Final boxes/offsets receive the already-resolved cell
             # size, so fractional child boxes are safe once tracks are proven.
@@ -273,7 +273,7 @@ def decorate(function: Function) -> Function:
 
 def _local_box_inputs(widget: Widget) -> tuple[bool, bool, bool, bool, bool]:
     """Resolve local scalar dependencies once per owning style generation."""
-    styles = widget.styles
+    styles = widget.geometry
     if type(styles) is not RenderStyles:
         return True, False, False, False, False
     # Retain the actual source so replacement cannot reuse an unrelated epoch.
@@ -343,7 +343,7 @@ def box_depends_on_available_height(widget: Widget, *, greedy: bool) -> bool:
         return True
     # Fractional width becomes auto only in optimal sizing. Normal placement
     # resolves the supplied fraction without calling get_content_width.
-    if (content_width and (not greedy or widget.styles.width.is_auto)
+    if (content_width and (not greedy or widget.geometry.width.is_auto)
             and widget._content_width_dependency.depends(widget)):
         return True
     if content_height:
@@ -352,9 +352,9 @@ def box_depends_on_available_height(widget: Widget, *, greedy: bool) -> bool:
 
 
 def _arrangement_wrapper_uses_height(widget: Widget) -> bool:
-    styles = widget.styles
+    styles = widget.geometry
     if (not widget._native_measurement_layout_hooks
             or styles.align_horizontal != "left" or styles.align_vertical != "top"):
         return True
-    return any(child.styles.is_docked or child.styles.is_split
-               or child.styles.overlay == "screen" for child in widget.displayed_children)
+    return any(child.geometry.is_docked or child.geometry.is_split
+               or child.geometry.overlay == "screen" for child in widget.displayed_children)

src/textual/_paint_state.py

@@ -1,17 +1,33 @@
-"""Immutable inherited paint values, resolved once per style/topology revision."""
-
+"""Inherited paint and the declaration inputs that produce it."""
 from __future__ import annotations
 
 from typing import NamedTuple
-
 from rich.style import NULL_STYLE, Style
+from textual.color import Color, TRANSPARENT
+
+
+class PaintLayer:
+    """One local colour layer, independent of how its inputs are declared."""
 
-from textual.color import Color
+    paint_foreground: Color | None
+    paint_background: Color | None
+    background_tint: Color
+    text_style: Style
+    text_opacity: float
+    layer_opacity: float
+    auto_color: bool
+    paint_key: int | None
+    paint_cacheable: bool
+
+    @property
+    def background_color(self) -> Color:
+        color = self.paint_background
+        return TRANSPARENT if color is None else color
 
 
 class PaintState(NamedTuple):
     parent: PaintState | None
-    style_key: int
+    style_key: int | None
     background: Color
     foreground: Color
     text_style: Style
@@ -21,50 +37,32 @@ class PaintState(NamedTuple):
     cacheable: bool = True
 
     def same_paint(self, other: PaintState) -> bool:
-        """Compare pixels, independently of the resolver's dependency lineage.
+        return self[2:8] == other[2:8]
 
-        Ancestor visibility or layout edits require fresh dependency resolution,
-        but retained paint remains valid when its resulting values are unchanged.
-        """
-        return (
-            self.background,
-            self.foreground,
-            self.text_style,
-            self.opacity,
-            self.base_background,
-            self.layered_background,
-        ) == (
-            other.background,
-            other.foreground,
-            other.text_style,
-            other.opacity,
-            other.base_background,
-            other.layered_background,
+    @classmethod
+    def resolve(cls, parent: PaintState, layer: PaintLayer) -> PaintState:
+        """Apply one declaration layer, preserving native alpha order."""
+        opacity = parent.opacity * layer.layer_opacity
+        local_background = layer.paint_background
+        tinted = layer.background_color.tint(layer.background_tint)
+        background = text_background = parent.background
+        if local_background is not None:
+            text_background = background + tinted
+            background += tinted.multiply_alpha(opacity)
+        local_foreground = layer.paint_foreground
+        foreground = parent.foreground if local_foreground is None else local_foreground
+        if layer.auto_color:
+            foreground = text_background.get_contrast_text(foreground.a)
+        return cls(
+            parent, layer.paint_key, background, foreground,
+            parent.text_style + layer.text_style, opacity,
+            parent.layered_background,
+            parent.layered_background + tinted.multiply_alpha(opacity),
+            parent.cacheable and layer.paint_cacheable,
         )
 
 
 EMPTY_PAINT = PaintState(
     None, -1, Color(0, 0, 0, 0), Color(255, 255, 255, 0),
     NULL_STYLE, 1.0, Color(0, 0, 0, 0), Color(0, 0, 0, 0),
 )
-
-
-def resolve_paint(parent: PaintState, styles) -> PaintState:
-    """Apply one declaration layer, preserving Textual's native alpha order."""
-    opacity = parent.opacity * styles.opacity
-    tinted = styles.background.tint(styles.background_tint)
-    background = parent.background
-    text_background = background
-    if styles.has_rule("background"):
-        text_background = background + tinted
-        background += tinted.multiply_alpha(opacity)
-    foreground = styles.color if styles.has_rule("color") else parent.foreground
-    if styles.has_rule("auto_color") and styles.auto_color:
-        foreground = text_background.get_contrast_text(foreground.a)
-    return PaintState(
-        parent, styles._cache_key, background, foreground,
-        parent.text_style + styles.text_style, opacity,
-        parent.layered_background,
-        parent.layered_background + tinted.multiply_alpha(opacity),
-        parent.cacheable,
-    )

src/textual/_resolve.py

@@ -8,7 +8,7 @@
 
 from textual.box_model import BoxModel
 from textual.css.scalar import Scalar
-from textual.css.styles import RenderStyles
+from textual.box_model import BoxGeometry
 from textual.geometry import Size
 
 if TYPE_CHECKING:
@@ -119,7 +119,7 @@ def resolve(
 
 
 def resolve_fraction_unit(
-    widget_styles: Iterable[RenderStyles],
+    widget_styles: Iterable[BoxGeometry],
     size: Size,
     viewport_size: Size,
     remaining_space: Fraction,
@@ -243,7 +243,7 @@ def resolve_box_models(
     fraction_height = size.height
     margin_size = size - margin
 
-    margins = [widget.styles.margin.totals for widget in widgets]
+    margins = [widget.geometry.margin.totals for widget in widgets]
 
     # Fixed box models
     box_models: list[BoxModel | None] = [
@@ -268,14 +268,14 @@ def resolve_box_models(
         return cast("list[BoxModel]", box_models)
 
     # If all box models have been calculated
-    widget_styles = [widget.styles for widget in widgets]
+    widget_styles = [widget.geometry for widget in widgets]
     if resolve_dimension == "width":
         total_remaining = int(
             sum(
                 [
                     box_model.width
                     for widget, box_model in zip(widgets, box_models)
-                    if (box_model is not None and widget.styles.overlay != "screen")
+                    if (box_model is not None and widget.geometry.overlay != "screen")
                 ]
             )
         )
@@ -302,7 +302,7 @@ def resolve_box_models(
                 [
                     box_model.height
                     for widget, box_model in zip(widgets, box_models)
-                    if (box_model is not None and widget.styles.overlay != "screen")
+                    if (box_model is not None and widget.geometry.overlay != "screen")
                 ]
             )
         )