Merge pull request #5133 from Textualize/tint

Textualize · Oct 21, 2024 · e3b1948 · e3b1948
2 parents 3daf4d7 + 793dd5b
commit e3b1948
Show file tree

Hide file tree

Showing 5 changed files with 131 additions and 69 deletions.
diff --git a/src/textual/color.py b/src/textual/color.py
@@ -399,6 +399,32 @@ def blend(
             new_alpha,
         )
 
+    @lru_cache(maxsize=1024)
+    def tint(self, color: Color) -> Color:
+        """Apply a tint to a color.
+
+        Similar to blend, but combines color and alpha.
+
+        Args:
+            color: A color with alpha component.
+
+        Returns:
+            New color
+        """
+
+        r1, g1, b1, a1, ansi1 = self
+        if ansi1 is not None:
+            return self
+        r2, g2, b2, a2, ansi2 = color
+        if ansi2 is not None:
+            return self
+        return Color(
+            int(r1 + (r2 - r1) * a2),
+            int(g1 + (g2 - g1) * a2),
+            int(b1 + (b2 - b1) * a2),
+            a1,
+        )
+
     def __add__(self, other: object) -> Color:
         if isinstance(other, Color):
             return self.blend(other, other.a, 1.0)

diff --git a/src/textual/dom.py b/src/textual/dom.py
@@ -1031,11 +1031,11 @@ def rich_style(self) -> Style:
             has_rule = styles.has_rule
             opacity *= styles.opacity
             if has_rule("background"):
-                text_background = (
-                    background + styles.background + styles.background_tint
+                text_background = background + styles.background.tint(
+                    styles.background_tint
                 )
                 background += (
-                    styles.background + styles.background_tint
+                    styles.background.tint(styles.background_tint)
                 ).multiply_alpha(opacity)
             else:
                 text_background = background
@@ -1124,7 +1124,7 @@ def background_colors(self) -> tuple[Color, Color]:
         for node in reversed(self.ancestors_with_self):
             styles = node.styles
             base_background = background
-            background += styles.background + styles.background_tint
+            background += styles.background.tint(styles.background_tint)
         return (base_background, background)
 
     @property
@@ -1140,7 +1140,7 @@ def _opacity_background_colors(self) -> tuple[Color, Color]:
             styles = node.styles
             base_background = background
             opacity *= styles.opacity
-            background += (styles.background + styles.background_tint).multiply_alpha(
+            background += styles.background.tint(styles.background_tint).multiply_alpha(
                 opacity
             )
         return (base_background, background)
@@ -1157,7 +1157,7 @@ def colors(self) -> tuple[Color, Color, Color, Color]:
         for node in reversed(self.ancestors_with_self):
             styles = node.styles
             base_background = background
-            background += styles.background + styles.background_tint
+            background += styles.background.tint(styles.background_tint)
             if styles.has_rule("color"):
                 base_color = color
                 if styles.auto_color: