fix: theme KDE Frameworks apps off Plasma

kcalc rendered white under the dark Kvantum theme. Off Plasma,
KStyleManager forces Breeze unless kdeglobals names a widgetStyle, and
KColorSchemeManager applies BreezeLight unless kdeglobals names a colour
scheme; qt6ct never forwards the portal's prefer-dark to Qt.

Generate a udt.colors KColorScheme from the Kvantum roles, install it to
~/.local/share/color-schemes/, and point kdeglobals at it and at
kvantum-dark.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 44 insertions, 0 deletions

diff --git a/bin/udt-palette b/bin/udt-palette
index fbe53e6..04451f7 100755
--- a/bin/udt-palette
+++ b/bin/udt-palette
@@ -404,6 +404,49 @@ def gen_kvantum(res, scheme, palette, template):
     return out
 
 
+def gen_kde(res, scheme, palette):
+    """KDE Frameworks apps: a KColorScheme file, the same roles as Kvantum.
+
+    Off Plasma, KColorSchemeManager ignores the Qt style's palette and falls
+    back to BreezeLight unless kdeglobals names a scheme, which is how kcalc
+    ended up white under a dark Kvantum theme. install.sh points kdeglobals at
+    this file. Colours are r,g,b triplets; the accent is the scheme's own,
+    since these apps read it once at startup.
+    """
+    def rgb(role):
+        r, g, b, _ = res[role]
+        return f"{r},{g},{b}"
+
+    fg = {
+        "ForegroundNormal": "fg", "ForegroundInactive": "fg_dim",
+        "ForegroundActive": "accent", "ForegroundLink": "accent",
+        "ForegroundVisited": "accent_bright", "ForegroundNegative": "critical",
+        "ForegroundNeutral": "warning", "ForegroundPositive": "success",
+        "DecorationFocus": "accent", "DecorationHover": "accent",
+    }
+    sets = {
+        "Window": ("bg", "surface"),
+        "View": ("bg_alt", "bg"),
+        "Button": ("surface", "surface_alt"),
+        "Header": ("bg", "surface"),
+        "Tooltip": ("bg_alt", "surface"),
+        "Complementary": ("bg_alt", "surface"),
+        "Selection": ("accent", "accent_dim"),
+    }
+    out = [f"# {BANNER.format(scheme=scheme)}", "[General]",
+           "ColorScheme=udt", "Name=udt", ""]
+    for name, (bg, bg_alt) in sets.items():
+        roles = dict(fg, BackgroundNormal=bg, BackgroundAlternate=bg_alt)
+        if name == "Selection":
+            # Text on a solid accent fill, so it takes the dark end.
+            roles.update(ForegroundNormal="bg", ForegroundActive="bg",
+                         ForegroundInactive="surface")
+        out.append(f"[Colors:{name}]")
+        out += [f"{k}={rgb(v)}" for k, v in sorted(roles.items())]
+        out.append("")
+    return "\n".join(out)
+
+
 # Shades upstream computed from a palette colour rather than taking one. Each
 # paints exactly one widget surface, so leaving them literal (the rule that is
 # right for the neutral greys) left twelve lavender and Macchiato-tinted spots
@@ -700,6 +743,7 @@ TARGETS = [
     ("templates/typora/udt.css", gen_typora, "templates/typora/udt.css.in"),
     ("templates/kvantum/theme.kvconfig", gen_kvantum, "templates/kvantum/theme.kvconfig.in"),
     ("templates/kvantum/theme.svg", gen_kvantum, "templates/kvantum/theme.svg.in"),
+    ("templates/kde/udt.colors", gen_kde, None),
     ("templates/sublime/udt.sublime-color-scheme", gen_sublime,
      "templates/sublime/udt.sublime-color-scheme.in"),
     ("templates/sublime/udt.sublime-theme", gen_sublime_theme,