text-opacity, dont render text when 0

sandbox/darren/just_a_box.css

@@ -1,8 +1,10 @@
 Screen {
+    layout: center;
     background: darkslategrey;
 }
 
 .box1 {
     background: darkmagenta;
     width: auto;
+    padding: 4 8;
 }

sandbox/darren/just_a_box.py

@@ -1,12 +1,22 @@
 from __future__ import annotations
 
 from textual.app import App, ComposeResult
-from textual.widgets import Static
+from textual.binding import Binding
+from textual.widgets import Static, Footer
 
 
 class JustABox(App):
+    BINDINGS = [
+        Binding(key="t", action="text_fade_out", description="text-opacity fade out")
+    ]
+
     def compose(self) -> ComposeResult:
         yield Static("Hello, world!", classes="box1")
+        yield Footer()
+
+    def action_text_fade_out(self) -> None:
+        box = self.query_one(".box1")
+        self.animator.animate(box.styles, "text_opacity", value=0.0, duration=1)
 
 
 app = JustABox(watch_css=True, css_path="../darren/just_a_box.css")

src/textual/renderables/text_opacity.py

@@ -1,6 +1,7 @@
 import functools
 from typing import Iterable
 
+from rich.cells import cell_len
 from rich.color import Color
 from rich.console import ConsoleOptions, Console, RenderResult, RenderableType
 from rich.segment import Segment
@@ -67,11 +68,16 @@ class TextOpacity:
 
             color = style.color
             bgcolor = style.bgcolor
-            if color and color.triplet and bgcolor and bgcolor.triplet:
-                color_style = _get_blended_style_cached(bgcolor, color, opacity)
-                yield _Segment(text, style + color_style)
+
+            if opacity > 0:
+                if color and color.triplet and bgcolor and bgcolor.triplet:
+                    color_style = _get_blended_style_cached(bgcolor, color, opacity)
+                    yield _Segment(text, style + color_style)
+                else:
+                    yield segment
             else:
-                yield segment
+                empty_text = cell_len(text) * " "
+                yield _Segment(empty_text, Style.from_color(bgcolor=bgcolor))
 
     def __rich_console__(
         self, console: Console, options: ConsoleOptions