document BT_RIO_PROTRUDE in the generated environ.ini

The button-protrusion dial shipped with no player-facing documentation -- it
lived only in the source comment and the KB, so a tester who found the buttons
too long (or wanted them longer) had no way to discover the knob.

Adds a block to the self-documenting default environ.ini, at the end of the
cockpit section beside the other display-shaping options (BT_MFD_SCALE,
BT_RADAR_SCALE, BT_RADAR_POS, BT_COCKPIT_TINT): what it does, that it is a
LONGER bar rather than a wider button (press target and imagery unchanged),
that it touches only the red MFD and yellow map buttons, the 10 default, 0 for
the original look, the 1-200 range, and the gotcha that it takes a NUMBER --
'on' parses to 0 and turns it off.

Verified by generating a fresh environ.ini from this build and reading the
block back as a player would see it.  The loader has no allowlist and refuses
only BT_JOYCONFIG, so the key applies from the file; a real env var still wins
over it, per the file's own contract.

NB the default is only written when environ.ini is ABSENT (and only beside
BTL4.RES), so existing installs keep their file and will not gain this text --
the handout/KB remain the channel for testers who already have one.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

context/glass-cockpit.md

@@ -115,6 +115,25 @@ each, so they cover the foot band too, and the hit test takes the first match
 what keeps 0x16/0x17/0x1F/0x1E reachable. That class of bug is why the verification below tests
 first-hit reachability, not mere presence.
 
+**Protrusion bonus — `BT_RIO_PROTRUDE` (2026-08-14, player request) [T2 receipt+screenshot].**
+Players asked for more of the RIO buttons to clear the glass so a FLASHING lamp is easier to
+notice. `BTRioBankMetricsFor` now adds a flat **+10px** to `strip` AFTER the scale, so the bar
+reaches that much further out on every renderer; `BT_RIO_PROTRUDE=<px>` tunes it (`0` restores
+the pre-2026-08-14 geometry). Deliberately FLAT, not scaled: the surround runs the glass at half
+scale where the strip sits on the 6px floor — a scaled bonus would help least exactly where the
+lamps are smallest — and that floor already trades proportionality for legibility. Because only
+`strip` moves, this touches exactly the **red MFD** and **yellow radar** buttons (+ the radar
+foot row) and grows them **outward only**: the layout anchors the inboard edge, so under-glass
+depth, button WIDTH and the press targets are unchanged. The **blue flight cells** are laid out
+from `cellW/cellH` and never see it (receipt: their bank bounds are byte-identical). Verified by
+`BT_RIOBANK_LOG` A/B — e.g. Heat MFD top button `y 21→11, h 126→136` with its bottom edge fixed
+at 147, bank bounds `252→272` tall, no negative coordinates — plus a surround screenshot pair.
+Relation to **#172**: the alert RING (`BT_ALERT_RING`, default off) answered the same night-16
+complaint after a *"+8px grown-face bloom"* was rejected on the bench as "the button got fat";
+this is a different shape — the lamp keeps its width and simply shows more of its own bar — so
+the ring stays optional. Desktop-glass affordance only; the pod's buttons are physical and
+backlit and never had this problem.
+
 ## Sticky window placement — BT_GLASS_LAYOUT (2026-07-28) [T2 round-trip-verified]
 
 The `BT_GLASS_PANELS` windows self-place in a pod-faithful ring around the main window

engine/MUNGA_L4/L4RIOBANK.cpp

@@ -25,6 +25,46 @@ namespace
 	const int minimumStrip    = 6;
 	const int defaultGap      = 4;
 
+	//-------------------------------------------------------------------
+	// PROTRUSION BONUS (2026-08-14, player request).  Flat pixels added to
+	// the lamp strip AFTER the scale, so the visible bar reaches this much
+	// further out of the glass on EVERY renderer.
+	//
+	// WHY FLAT, not scaled: the ask is on-screen noticeability of a
+	// FLASHING lamp, and the surround runs the glass at half scale, where
+	// the strip lands on the `minimumStrip` floor (~6px) -- a scaled bonus
+	// would give the surround half the help exactly where the lamps are
+	// smallest.  The floor above already establishes legibility over strict
+	// proportionality for this field; this is the same trade, sized by the
+	// players.  It is a DESKTOP-GLASS affordance: the pod's buttons are
+	// physical and backlit and have never had this problem.
+	//
+	// Scope: only the strip -- so only the RED MFD buttons and the YELLOW
+	// radar buttons/foot row grow, and they grow OUTWARD ONLY (the layout
+	// anchors the inboard edge; under-glass depth is unchanged).  The BLUE
+	// flight cells are laid out from cellW/cellH and never see this.
+	//
+	// Relation to #172: the alert RING (BT_ALERT_RING, default off) was the
+	// answer to the same night-16 complaint after a "+8px grown-face bloom"
+	// was rejected on the bench as "the button got fat".  This is a
+	// different shape -- the lamp keeps its width and simply shows more of
+	// its own bar -- and it is unconditional, so the ring stays optional.
+	//-------------------------------------------------------------------
+	const int defaultProtrude = 10;
+
+	int ProtrudeBonus()
+	{
+		static int cached = -1;
+		if (cached < 0)
+		{
+			const char *e = getenv("BT_RIO_PROTRUDE");	// tune by eye; 0 = pre-2026-08-14
+			cached = (e != 0) ? atoi(e) : defaultProtrude;
+			if (cached < 0)   cached = 0;
+			if (cached > 200) cached = 200;
+		}
+		return cached;
+	}
+
 	//-------------------------------------------------------------------
 	// Per-column horizontal nudge for the 4 MFD buttons, left->right, so
 	// they line up with the (unevenly spaced) DISPLAY / PROGRAM / ...
@@ -111,6 +151,7 @@ void
 
 	int strip = Scaled(nativeStrip, shortAxis, nativeShortAxis);
 	if (strip < minimumStrip) strip = minimumStrip;
+	strip += ProtrudeBonus();			// player-requested reach (see above)
 
 	out->strip = strip;
 	out->gap   = defaultGap;

game/btl4main.cpp

@@ -394,6 +394,20 @@ static const char *kEnvironIniDefault =
 "# Phosphor colour of the mono MFDs, RRGGBB.  Default is a green tube.\n"
 "#BT_COCKPIT_TINT=21FF42\n"
 "\n"
+"# How far the lit RIO buttons reach out past the edge of a display, in pixels.\n"
+"# The pod's buttons were physical and backlit; on glass they are a thin bar\n"
+"# along the display edge, and a FLASHING one is easy to miss.  This is how much\n"
+"# more of that bar shows -- a LONGER bar, not a wider button: the button keeps\n"
+"# its width, the display picture still covers everything it did before, and the\n"
+"# whole display stays clickable.  Red (MFD) and yellow (map) buttons only; the\n"
+"# blue flight block has no glass to hide behind, so it never changes.\n"
+"#   10    the default\n"
+"#   0     back to the original thin bar\n"
+"#   1-200 anything in between\n"
+"# Give it a NUMBER -- a word like 'on' counts as 0 and turns it off.  In the\n"
+"# exploded view (BT_GLASS_PANELS) the windows grow to fit the longer buttons.\n"
+"#BT_RIO_PROTRUDE=10\n"
+"\n"
 "# ---- Display ----------------------------------------------------------------\n"
 "\n"
 "# The cockpit is fitted into the window at ONE uniform scale, centred, with\n"