From 7d85157c3c454a445d5bd1450791cb22e5815fe2 Mon Sep 17 00:00:00 2001
From: en-ot <andrey.mikhaylov.n@gmail.com>
Date: Thu, 1 Jul 2021 11:58:11 +0300
Subject: [PATCH] FAST_UNICODE_INDEX - faster binary search for index from
 unicode code point, for ordered by code point fonts only

---
 Extensions/Smooth_font.cpp | 33 +++++++++++++++++++++++++++++++++
 User_Setup.h               |  2 ++
 2 files changed, 35 insertions(+)

diff --git a/Extensions/Smooth_font.cpp b/Extensions/Smooth_font.cpp
index fa94c59..ed66033 100644
--- a/Extensions/Smooth_font.cpp
+++ b/Extensions/Smooth_font.cpp
@@ -338,6 +338,37 @@ uint32_t TFT_eSPI::readInt32(void)
 ** Function name:           getUnicodeIndex
 ** Description:             Get the font file index of a Unicode character
 *************************************************************************************x*/
+
+#ifdef FAST_UNICODE_INDEX
+bool TFT_eSPI::getUnicodeIndex(uint16_t unicode, uint16_t *index)
+{
+  int above = gFont.gCount;
+  int bottom = 0;
+  int i = above / 2;
+  do
+  {
+    uint16_t code = gUnicode[i];
+    if (code == unicode)
+    {
+      *index = i;
+      return true;
+    }
+    if (code > unicode)
+    {
+      above = i;
+    }
+    else
+    {
+      bottom = i+1;
+    }
+    i = (above+bottom)/2;
+  } while (above > bottom);
+
+  return false;
+}
+
+#else
+
 bool TFT_eSPI::getUnicodeIndex(uint16_t unicode, uint16_t *index)
 {
   for (uint16_t i = 0; i < gFont.gCount; i++)
@@ -351,6 +382,8 @@ bool TFT_eSPI::getUnicodeIndex(uint16_t unicode, uint16_t *index)
   return false;
 }
 
+#endif
+
 
 /***************************************************************************************
 ** Function name:           drawGlyph
diff --git a/User_Setup.h b/User_Setup.h
index a5cadeb..e47499b 100644
--- a/User_Setup.h
+++ b/User_Setup.h
@@ -304,6 +304,8 @@
 // this will save ~20kbytes of FLASH
 #define SMOOTH_FONT
 
+// Smooth font improvements
+#define FAST_UNICODE_INDEX
 
 // ##################################################################################
 //