From 7e47305aa4799bdb54c6f921c241e0dcaec0555f Mon Sep 17 00:00:00 2001
From: Marisa the Magician <marisa@sayachan.org>
Date: Thu, 22 Sep 2022 17:24:02 +0200
Subject: [PATCH] mkfont update, now supports variable width fonts.

---
 mkfont.c | 67 ++++++++++++++++++++++++++------------------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/mkfont.c b/mkfont.c
index c3a826d..67a4405 100644
--- a/mkfont.c
+++ b/mkfont.c
@@ -27,10 +27,12 @@
 /*
 	Known bugs/limitations:
 
-	- There is currently no handling of proportional fonts whatsoever, this
-	  expects monospaced fonts where all glyphs have the same size. Dunno
-	  if I'd ever bother with that in the future.
-	- Non-bitmap fonts might sometimes spew lots of (out of bounds) drawing
+	- There is no handling of proportional fonts where glyphs are wider
+	  than their advance length. As this isn't supported by GZDoom itself,
+	  it's not a priority either. There's no way to encode the "real width"
+	  of a glyph into the PNG. Also, glyphs might end up rendered with
+	  cropped sides.
+	- Non-bitmap fonts might sometimes spew lots of "out of bounds" drawing
 	  warnings. This is mainly due to the peculiarities of antialiasing.
 	- Doesn't handle unicode blocks beyond the basic multilingual plane,
 	  might actually be an issue with freetype itself, or the fonts I use,
@@ -116,9 +118,10 @@ FT_Library ftlib;
 FT_Face fnt;
 
 int iw, ih;
-int w, h, pxsiz;
+int w, h, pxsiz, datsiz;
 uint8_t *idata;
 
+int autosize = 0;
 int gradient = 0;
 int upshift = 0;
 
@@ -353,11 +356,7 @@ int main( int argc, char **argv )
 	}
 	uint32_t range[2] = {0x0000,0x00FF};
 	sscanf(argv[2],"%d",&pxsiz);
-	if ( !strcmp(argv[3],"auto") )
-	{
-		w = -1;
-		h = -1;
-	}
+	if ( !strcmp(argv[3],"auto") ) autosize = 1;
 	else sscanf(argv[3],"%dx%d",&w,&h);
 	sscanf(argv[4],"%x-%x",&range[0],&range[1]);
 	if ( argc > 5 ) sscanf(argv[5],"%d",&gradient);
@@ -372,7 +371,7 @@ int main( int argc, char **argv )
 	{
 		if ( fnt->num_fixed_sizes <= 0 )
 		{
-			fprintf(stderr,"error: font pixel size of '%d' not available\n",pxsiz);
+			fprintf(stderr,"error: font pixel size of '%d' not available.\n",pxsiz);
 			return 8;
 		}
 		fprintf(stderr,"warning: failed to set pixel size '%d', trying fixed sizes.\n",pxsiz);
@@ -442,35 +441,19 @@ int main( int argc, char **argv )
 	}
 	if ( rightshift )
 		fprintf(stderr,"info: right shift detected, grAb X offset %d will be used.\n",rightshift);
-	// third pass to compute the "real" cell size
-	if ( w == -1 )
+	// third pass to compute the maximum cell size (for memory allocation)
+	if ( autosize )
 	{
+		h = pxsiz+1;	// should be fine
 		for ( uint32_t i=range[0]; i<=range[1]; i++ )
 		{
 			FT_UInt glyph = FT_Get_Char_Index(fnt,i);
 			if ( !glyph || FT_Load_Glyph(fnt,glyph,LOADFLAGS) ) continue;
 			FT_Render_Glyph(fnt->glyph,RENDERMODE);
-			int valid = 0;
-			for ( unsigned j=0; j<fnt->glyph->bitmap.rows; j++ )
-				valid |= valid_row(&fnt->glyph->bitmap,j);
-			if ( !valid ) continue;
-			int gw = fnt->glyph->bitmap_left+rightshift;
-			int gh = (upshift+xupshift+1)+(pxsiz-fnt->glyph->bitmap_top);
-			int mw = 0;
-			int mh = 0;
-			for ( unsigned j=0; j<fnt->glyph->bitmap.rows; j++ )
-			{
-				if ( !valid_row(&fnt->glyph->bitmap,j) ) continue;
-				int rw = row_width(&fnt->glyph->bitmap,j);
-				if ( rw > mw ) mw = rw;
-				mh = j;
-			}
-			gw += mw+1;
-			gh += mh+1;
-			if ( gw > w ) w = gw;
-			if ( gh > h ) h = gh;
+			int adv = fnt->glyph->linearHoriAdvance>>16;
+			if ( adv > w ) w = adv;
 		}
-		fprintf(stderr,"info: guessed cell size is %dx%d.\n",w,h);
+		fprintf(stderr,"info: max cell size is %dx%d.\n",w,h);
 	}
 	iw = w+1;
 	ih = h+1;
@@ -480,17 +463,29 @@ int main( int argc, char **argv )
 		iw++;
 		ih++;
 	}
+	datsiz = palsize?(iw*ih*4):(iw*ih*2);
 	fprintf(stderr,"info: gradient selected is '%s'.\n",grads[gradient&7]);
-	idata = calloc(iw*ih,palsize?4:2);
+	idata = calloc(datsiz,1);
 	uint32_t drawn = 0;
 	for ( uint32_t i=range[0]; i<=range[1]; i++ )
 	{
 		FT_UInt glyph = FT_Get_Char_Index(fnt,i);
 		if ( !glyph || FT_Load_Glyph(fnt,glyph,LOADFLAGS) ) continue;
 		FT_Render_Glyph(fnt->glyph,RENDERMODE);
+		int valid = 0;
+		for ( unsigned j=0; j<fnt->glyph->bitmap.rows; j++ )
+			valid |= valid_row(&fnt->glyph->bitmap,j);
+		if ( !valid ) continue;
+		if ( autosize )
+		{
+			// readjust cell width (but not height) for this character
+			int adv = fnt->glyph->linearHoriAdvance>>16;
+			w = adv;
+			iw = w+((gradient&4)?2:1);
+		}
 		int xx = rightshift;
 		int yy = upshift+xupshift+1;
-		int valid;
+		valid = 0;
 		oob = 0;
 		if ( gradient&4 )
 		{
@@ -519,7 +514,7 @@ int main( int argc, char **argv )
 			writepng(fname,idata,iw,ih,palsize?(iw*4):(iw*2));
 			drawn++;
 		}
-		memset(idata,0,palsize?(iw*ih*4):(iw*ih*2));
+		memset(idata,0,datsiz);
 	}
 	fprintf(stderr,"info: %u glyphs drawn.\n",drawn);
 	free(idata);