From a63e33344928b7f767b97aced995a84ad9b53de0 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 23 Nov 2012 10:43:08 +0200
Subject: [PATCH] Add an option to invert colors

---
 ttf2png.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/ttf2png.c b/ttf2png.c
index b61d51d..c77cd58 100644
--- a/ttf2png.c
+++ b/ttf2png.c
@@ -73,6 +73,7 @@ int main(int argc, char **argv)
 	char autohinter = 0;
 	char seq = 0;
 	char alpha = 0;
+	char invert = 0;
 	char pack = 0;
 
 	FT_Library freetype;
@@ -92,7 +93,7 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:p")) != -1)
+	while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:pi")) != -1)
 	{
 		char *ptr;
 		int  temp;
@@ -175,6 +176,9 @@ int main(int argc, char **argv)
 		case 'p':
 			pack = 1;
 			break;
+		case 'i':
+			invert = 1;
+			break;
 		}
 	}
 	if(!strcmp(out_fn, "-"))
@@ -224,6 +228,11 @@ int main(int argc, char **argv)
 		render_packed(&font);
 	else
 		render_grid(&font, cellw, cellh, cpl, seq);
+	if(invert)
+	{
+		for(i=0; i<font.image.w*font.image.h; ++i)
+			font.image.data[i] = 255-font.image.data[i];
+	}
 	save_png(out_fn, &font.image, alpha);
 	if(def_fn)
 		save_defs(def_fn, &font);
@@ -265,6 +274,7 @@ void usage()
 		"  -o  Output file name (or - for stdout) [font.png]\n"
 		"  -a  Force autohinter\n"
 		"  -t  Render font to alpha channel\n"
+		"  -i  Invert colors of the glyphs\n"
 		"  -v  Increase the level of verbosity\n"
 		"  -e  Use cells in sequence, rather than by code\n"
 		"  -p  Pack the glyphs tightly instead of in a grid\n"
-- 
2.43.0