From 9a7c6bdcf2ed686e41a15bbf6a3fbd9e8517dc6a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Thu, 24 Jun 2021 19:15:53 +0200
Subject: [PATCH] term: CELL_COMB_CHARS chars are keys, not indices -> more
 range is better

Bump the available key range to 30 bits. This helps reduce key
collisions when handling a large amount of grapheme clusters.
---
 terminal.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/terminal.h b/terminal.h
index 00c4221f..385b36e0 100644
--- a/terminal.h
+++ b/terminal.h
@@ -51,9 +51,10 @@ struct attributes {
 };
 static_assert(sizeof(struct attributes) == 8, "VT attribute struct too large");
 
-#define CELL_COMB_CHARS_LO    0x40000000ul
-#define CELL_COMB_CHARS_HI    0x400ffffful
-#define CELL_SPACER           0x40100000ul
+/* Last valid Unicode code point is 0x0010FFFFul */
+#define CELL_COMB_CHARS_LO          0x00200000ul
+#define CELL_COMB_CHARS_HI          (CELL_COMB_CHARS_LO + 0x3fffffff)
+#define CELL_SPACER                 (CELL_COMB_CHARS_HI + 1)
 
 struct cell {
     wchar_t wc;