acme looks like acme; every theme gets acme's button, scroll column and 2px rules

acme takes plan9port's own colours (acme.c iconinit, draw.h): selections
#eeee9e in the body and #9eeeee in the tag, black ink; exec and look sweeps
#aa0000 and #006600, white ink; a #99994c scrollbar under a #ffffea thumb;
black rules; a #8888cc tag/body rule and column button.

Every theme: the grip is acme's button, its tag row's full height, in one
scroll column with the scrollbar (rail_px, 12 at a 17px tagline, scaled,
times GripWidth, a percent, default 150; same x0/x1 to the pixel):
focused clean = solid box; focused dirty = box_dirty filled to a box ring
(acme's modbutton); unfocused clean = a box_border ring round the tag's
ground; unfocused dirty = box_dirty a pixel inside that ring. The grid, which
has no ring, marks dirty with a bold * on box_dirty in the grip's second cell
and fills an unfocused grip halfway to its ring. Regions carry a dirty flag.
Column buttons are the same shape, solid. 2px rules between columns and
stacked panes (inside the tag band's slack), none at the window edge; a 1px
tag/body rule halfway between tag and page.

Theme data: tag_sel_bg, sweep_bg/fg, tag_rule, rule_px, rail_px, box_border,
box_dirty. Chrome: rule_px, tag_rule, rail_px, grip_border, grip_focus_ring;
a comptime guard on Chrome's layout forces a wire bump once v8 ships.
Structural rules are exempt from the focus-indicator rule (docs/effects.md).

Tests: acme widths; stacked rule in the slack at two tagline sizes; every
grip-column pixel is band, button, ring or rule, and the button shares the
scrollbar's x0/x1 (4 metrics x top/bottom x focus x dirty); the four grip
states distinct in every native theme with a non-colour dirty cue in the
grid; wire round-trip of the new fields.

Shared files: src/colors.zig, src/surface.zig, src/body_layer.zig,
src/tagline.zig, src/detached/wire.zig, docs/themes.md, docs/config.md,
docs/effects.md, 21 snapshot goldens (the grip cells only),
test/gui-goldens.txt.

Motion flavours differ by design, and drive notice drops and pane moves

1 files changed, 25 insertions, 0 deletions

diff --git a/src/colors.zig b/src/colors.zig
index aeff7b00..25aa838f 100644
--- a/src/colors.zig
+++ b/src/colors.zig
@@ -63,6 +63,29 @@ pub const Theme = struct {
     // The current line number is a quiet foreground cue, not a tag-colored
     // background block. Older themes fall back to their normal gutter ink.
     lineno_active: ?[3]u8 = null,
+    /// A tag's selection, where it differs from the body's (acme's #9eeeee).
+    tag_sel_bg: ?[3]u8 = null,
+    /// Each pointer button's sweep, select, exec and look (Mouse.Button
+    /// order), and the ink over it. Unset, tints of `sel_bg` in `sel_fg`.
+    sweep_bg: ?[3][3]u8 = null,
+    sweep_fg: ?[3][3]u8 = null,
+    /// A pixel shell's rules, in pixels (2 unset); the rule between a tag
+    /// and its body is always one.
+    rule_px: ?u8 = null,
+    /// A grip is acme's button: `box` filled when focused, else a ring of
+    /// `box_border` (unset: `box_dim`) round the tag's ground; `box_dirty`
+    /// (unset: `diagnostic_warning`, then `num`) fills it, in either ring,
+    /// while its file is unsaved.
+    box_border: ?[3]u8 = null,
+    box_dirty: ?[3]u8 = null,
+    /// The rule between a pane's tag and its body, one pixel, quieter than
+    /// the rules between panes (acme's #8888cc under its 2px black ones).
+    /// Unset, halfway between the tag's ground and the page.
+    tag_rule: ?[3]u8 = null,
+    /// A pixel shell's scroll column, the grip's button over the scrollbar,
+    /// in pixels at a 17px tagline, the thumb one narrower (acme's 12px
+    /// Scrollwid, the default).
+    rail_px: ?u8 = null,
 };
 
 const curated = struct {
@@ -108,6 +131,8 @@ fn fold(comptime C: type) [@typeInfo(C).@"struct".decls.len]Theme {
 }
 
 pub const themes = fold(curated) ++ fold(@import("generated_themes"));
+/// The first `native_count` of `themes` are pardes's own; the rest imported.
+pub const native_count = @typeInfo(curated).@"struct".decls.len;
 
 /// Original and classic-inspired Pardes palettes precede retained imports.
 pub const native_theme_count = 15;