sl0ppty: plain ASCII for the frame's buttons

_ for minimise, # for zoom, * for the way back, x for close.

Box-drawing and block characters were each tried and each looked unevenly
spaced, which is the answer: the cells are even every time, and what differs is
how much of its own cell a glyph fills. That is a property of the font, not
something to be fixed from here, and single-width ASCII of a similar weight is
the way to stop asking the question.

The measurement stays, so a mark is still yours to change and may be more than
one character. The config note now says what the three attempts established
rather than what I expected each time.

4 files changed, 16 insertions, 13 deletions

diff --git a/README.md b/README.md
index d0d412a..cbfdd5e 100644
--- a/README.md
+++ b/README.md
@@ -78,7 +78,7 @@ rewrites its title cannot undo it; clear the name and the pane goes back to the
 program's title. The name is only the title *text*: the rest of the top border
 is still the top edge, and still splits upward when clicked.
 
-**Zoom a pane** with `C-a z` or the `□` button in its top-right corner, and it
+**Zoom a pane** with `C-a z` or the `#` button in its top-right corner, and it
 fills the tab until you put it back; the other panes keep running, they are
 just not drawn. `x` beside it closes the pane. `pane_buttons false` takes both
 buttons off without touching the keybindings.
diff --git a/config/config.kdl b/config/config.kdl
index e89a8ac..689c7c9 100644
--- a/config/config.kdl
+++ b/config/config.kdl
@@ -53,15 +53,18 @@ title_inset 2
 // the setting is about the affordance and not the verb.
 pane_buttons true
 
-// The buttons are evenly spaced whatever is in them, but how even they *look*
-// depends on the glyphs: a light character floating in a mostly-empty cell
-// donates that space to the gap beside it. Emoji are worse -- many terminals
-// draw them two columns wide while chrome here is booked as one -- so avoid
-// those. A mark may be more than one character; the button is measured rather
-// than assumed, so "[]" and "][" work too if you prefer them. Put the character itself
+// Plain single-width ASCII, after box-drawing and block characters were each
+// tried and each looked unevenly spaced: the cells are even, but a glyph that
+// does not fill its own cell hands that space to the gap beside it, and how
+// much it hands over depends on the font. ASCII of a similar weight sidesteps
+// the question. Emoji are the worst case -- many terminals draw them two
+// columns wide while chrome here is booked as one.
+//
+// A mark may be more than one character; the button is measured rather than
+// assumed, so "[]" and "][" work if you prefer them. Put the character itself
 // here; this file has no \u escape.
-zoom_mark "□"
-zoom_on_mark "▣"
+zoom_mark "#"
+zoom_on_mark "*"
 close_mark "x"
 min_mark "_"
 
diff --git a/src/config.c b/src/config.c
index 6253f08..7159d47 100644
--- a/src/config.c
+++ b/src/config.c
@@ -172,8 +172,8 @@ void config_defaults(config_t *c) {
   c->title_align = ALIGN_CENTER;
   c->title_inset = 2;
   c->pane_buttons = true;
-  snprintf(c->zoom_mark, sizeof c->zoom_mark, "\u25a1");
-  snprintf(c->zoom_on_mark, sizeof c->zoom_on_mark, "\u25a3");
+  snprintf(c->zoom_mark, sizeof c->zoom_mark, "#");
+  snprintf(c->zoom_on_mark, sizeof c->zoom_on_mark, "*");
   snprintf(c->close_mark, sizeof c->close_mark, "x");
   snprintf(c->min_mark, sizeof c->min_mark, "_");
   c->bell_indicator = true;
diff --git a/tests/test_zoom.py b/tests/test_zoom.py
index a5c9fba..285269d 100644
--- a/tests/test_zoom.py
+++ b/tests/test_zoom.py
@@ -76,7 +76,7 @@ def test_the_button_toggles_and_says_which_way():
         s.click(b["x"] + 1, b["y"])
         s.settle(20)
         check("clicking it zooms", len(visible(s)) == 1, str(s.panes()))
-        check("and the mark says so", "\u25a3" in s.snapshot().line(2),
+        check("and the mark says so", "*" in s.snapshot().line(2),
               repr(s.snapshot().line(2)[-14:]))
 
         # The button moved: the pane it belongs to just became the whole tab.
@@ -85,7 +85,7 @@ def test_the_button_toggles_and_says_which_way():
         s.settle(20)
         check("clicking it again puts it back", len(visible(s)) == 2,
               str(s.panes()))
-        check("and the mark goes back too", "\u25a1" in s.snapshot().line(2),
+        check("and the mark goes back too", "#" in s.snapshot().line(2),
               repr(s.snapshot().line(2)[-14:]))