From 57f12a3121522fb1d70228596c0252cc3a903727 Mon Sep 17 00:00:00 2001
From: Timo Korvola <tkorvola@iki.fi>
Date: Tue, 27 Mar 2018 02:44:50 +0300
Subject: [PATCH] Fix cursor positioning.

Input text width was computed incorrectly.
---
 src/sdl/sf_fonts.c | 10 +++++-----
 src/sdl/sf_frotz.h |  6 ++++++
 src/sdl/sf_video.c |  4 ++--
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/src/sdl/sf_fonts.c b/src/sdl/sf_fonts.c
index 832819d..cc9a183 100644
--- a/src/sdl/sf_fonts.c
+++ b/src/sdl/sf_fonts.c
@@ -439,11 +439,11 @@ int os_check_unicode(int font, zword c)
   return ((current.font->hasglyph(current.font,c,0) != 0) ? 3 : 2);
   }
 
-static int charwidth( zword c, int *oh)
+int sf_charwidth( zword c, int *oh)
   {
   SF_glyph *g; int ww = 0;
-  if (c == ZC_INDENT) return (3*charwidth(' ',oh));
-  if (c == ZC_GAP) return (2*charwidth(' ',oh));
+  if (c == ZC_INDENT) return (3*sf_charwidth(' ',oh));
+  if (c == ZC_GAP) return (2*sf_charwidth(' ',oh));
   *oh = 0;
   g = current.font->getglyph(current.font,c,1);
   if (g)
@@ -464,7 +464,7 @@ static int charwidth( zword c, int *oh)
 int os_char_width(zchar c)
   {
   int w, oh;
-  w = charwidth( c, &oh);
+  w = sf_charwidth( c, &oh);
   return (w+oh);
   }
 
@@ -583,7 +583,7 @@ int os_string_width(const zchar *s)
 		os_set_font(*s++);
 		}
 	else
-		width += charwidth(c,&oh);
+		width += sf_charwidth(c,&oh);
 	}
   sf_poptextsettings();
 
diff --git a/src/sdl/sf_frotz.h b/src/sdl/sf_frotz.h
index 8e706f6..b6da1d4 100644
--- a/src/sdl/sf_frotz.h
+++ b/src/sdl/sf_frotz.h
@@ -160,6 +160,12 @@ typedef struct {
 
 SF_textsetting * sf_curtextsetting(void);
 
+/**
+ * Return the advance width of character c.
+ * Store glyph width minus advance width to oh ("overhang").
+ */
+int sf_charwidth( zword c, int *oh);
+
 void sf_writeglyph( SF_glyph *g);
 
 void sf_fillrect( unsigned long color, int x, int y, int w, int h);
diff --git a/src/sdl/sf_video.c b/src/sdl/sf_video.c
index c54ed13..75f358e 100644
--- a/src/sdl/sf_video.c
+++ b/src/sdl/sf_video.c
@@ -928,8 +928,8 @@ void sf_DrawInput(zchar * buffer, int pos, int ptx, int pty, int width, bool cur
 
   if (cursor)
 	{
-	int wid=0, i=0;
-	while (i<pos) wid += os_char_width(buffer[i++]);
+	int wid=0, i=0, oh;
+	while (i<pos) wid += sf_charwidth(buffer[i++], &oh);
 	drawthecursor(ptx+wid,pty,1);
 	}
 
-- 
2.34.1