Add opacity support

src/textual/_opacity.py

@@ -0,0 +1,30 @@
+from typing import Iterable
+
+from rich.segment import Segment
+from rich.style import Style
+
+from textual.color import Color
+from textual.renderables._blend_colors import blend_colors
+
+
+def _apply_widget_opacity(
+    segments: Iterable[Segment],
+    base_background: Color,
+    opacity: float,
+) -> Iterable[Segment]:
+    _Segment = Segment
+    for segment in segments:
+        text, style, _ = segment
+        if not style:
+            yield segment
+            continue
+
+        color = style.color
+        bgcolor = style.bgcolor
+        if color and color.triplet and bgcolor and bgcolor.triplet:
+            blended_foreground = blend_colors(color, base_background, ratio=opacity)
+            blended_background = blend_colors(bgcolor, base_background, ratio=opacity)
+            blended_style = Style(color=blended_foreground, bgcolor=blended_background)
+            yield _Segment(text, style + blended_style)
+        else:
+            yield segment

src/textual/_styles_cache.py

@@ -7,11 +7,12 @@ from rich.segment import Segment
 from rich.style import Style
 
 from ._border import get_box, render_row
+from ._opacity import _apply_widget_opacity
 from ._segment_tools import line_crop, line_pad, line_trim
 from ._types import Lines
 from .color import Color
 from .geometry import Region, Size, Spacing
-from .renderables.opacity import Opacity
+from .renderables.text_opacity import TextOpacity
 from .renderables.tint import Tint
 
 if sys.version_info >= (3, 10):
@@ -238,9 +239,14 @@ class StylesCache:
                 list[Segment]: New list of segments
             """
             if styles.text_opacity != 1.0:
-                segments = Opacity.process_segments(segments, styles.text_opacity)
+                segments = TextOpacity.process_segments(segments, styles.text_opacity)
             if styles.tint.a:
                 segments = Tint.process_segments(segments, styles.tint)
+            if styles.opacity != 1.0:
+                segments = _apply_widget_opacity(
+                    segments, base_background, styles.opacity
+                )
+
             return segments if isinstance(segments, list) else list(segments)
 
         line: Iterable[Segment]

src/textual/css/styles.py

@@ -87,6 +87,7 @@ class RulesMap(TypedDict, total=False):
     background: Color
     text_style: Style
 
+    opacity: float
     text_opacity: float
 
     padding: Spacing
@@ -184,6 +185,7 @@ class StylesBase(ABC):
         "max_height",
         "color",
         "background",
+        "opacity",
         "text_opacity",
         "tint",
         "scrollbar_color",
@@ -204,6 +206,7 @@ class StylesBase(ABC):
     background = ColorProperty(Color(0, 0, 0, 0), background=True)
     text_style = StyleFlagsProperty()
 
+    opacity = FractionalProperty()
     text_opacity = FractionalProperty()
 
     padding = SpacingProperty()

src/textual/renderables/text_opacity.py

@@ -31,7 +31,7 @@ def _get_blended_style_cached(
     )
 
 
-class Opacity:
+class TextOpacity:
     """Blend foreground in to background."""
 
     def __init__(self, renderable: RenderableType, opacity: float = 1.0) -> None:
@@ -96,7 +96,7 @@ if __name__ == "__main__":
     )
     console.print(panel)
 
-    opacity_panel = Opacity(panel, opacity=0.5)
+    opacity_panel = TextOpacity(panel, opacity=0.5)
     console.print(opacity_panel)
 
     def frange(start, end, step):

src/textual/widget.py

@@ -1266,6 +1266,7 @@ class Widget(DOMNode):
         width, height = self.size
         renderable = self.render()
         renderable = self.post_render(renderable)
+        renderable = self.apply_opacity(renderable)
         options = self._console.options.update_dimensions(width, height).update(
             highlight=False
         )

src/textual/widgets/tabs.py

@@ -14,7 +14,7 @@ from textual import events
 from textual._layout_resolve import layout_resolve, Edge
 from textual.keys import Keys
 from textual.reactive import Reactive
-from textual.renderables.opacity import Opacity
+from textual.renderables.text_opacity import TextOpacity
 from textual.renderables.underline_bar import UnderlineBar
 from textual.widget import Widget
 
@@ -125,7 +125,7 @@ class TabsRenderable:
                     style=inactive_tab_style
                     + Style.from_meta({"@click": f"range_clicked('{tab.name}')"}),
                 )
-                dimmed_tab_content = Opacity(
+                dimmed_tab_content = TextOpacity(
                     tab_content, opacity=self.inactive_text_opacity
                 )
                 segments = console.render(dimmed_tab_content)

tests/renderables/test_text_opacity.py

@@ -2,7 +2,7 @@ import pytest
 from rich.text import Text
 
 from tests.utilities.render import render
-from textual.renderables.opacity import Opacity
+from textual.renderables.text_opacity import TextOpacity
 
 STOP = "\x1b[0m"
 
@@ -12,39 +12,39 @@ def text():
     return Text("Hello, world!", style="#ff0000 on #00ff00", end="")
 
 
-def test_simple_opacity(text):
+def test_simple_text_opacity(text):
     blended_red_on_green = "\x1b[38;2;127;127;0;48;2;0;255;0m"
-    assert render(Opacity(text, opacity=.5)) == (
+    assert render(TextOpacity(text, opacity=.5)) == (
         f"{blended_red_on_green}Hello, world!{STOP}"
     )
 
 
 def test_value_zero_sets_foreground_color_to_background_color(text):
     foreground = background = "0;255;0"
-    assert render(Opacity(text, opacity=0)) == (
+    assert render(TextOpacity(text, opacity=0)) == (
         f"\x1b[38;2;{foreground};48;2;{background}mHello, world!{STOP}"
     )
 
 
-def test_opacity_value_of_one_noop(text):
-    assert render(Opacity(text, opacity=1)) == render(text)
+def test_text_opacity_value_of_one_noop(text):
+    assert render(TextOpacity(text, opacity=1)) == render(text)
 
 
 def test_ansi_colors_noop():
     ansi_colored_text = Text("Hello, world!", style="red on green", end="")
-    assert render(Opacity(ansi_colored_text, opacity=.5)) == render(ansi_colored_text)
+    assert render(TextOpacity(ansi_colored_text, opacity=.5)) == render(ansi_colored_text)
 
 
-def test_opacity_no_style_noop():
+def test_text_opacity_no_style_noop():
     text_no_style = Text("Hello, world!", end="")
-    assert render(Opacity(text_no_style, opacity=.2)) == render(text_no_style)
+    assert render(TextOpacity(text_no_style, opacity=.2)) == render(text_no_style)
 
 
-def test_opacity_only_fg_noop():
+def test_text_opacity_only_fg_noop():
     text_only_fg = Text("Hello, world!", style="#ff0000", end="")
-    assert render(Opacity(text_only_fg, opacity=.5)) == render(text_only_fg)
+    assert render(TextOpacity(text_only_fg, opacity=.5)) == render(text_only_fg)
 
 
-def test_opacity_only_bg_noop():
+def test_text_opacity_only_bg_noop():
     text_only_bg = Text("Hello, world!", style="on #ff0000", end="")
-    assert render(Opacity(text_only_bg, opacity=.5)) == render(text_only_bg)
+    assert render(TextOpacity(text_only_bg, opacity=.5)) == render(text_only_bg)