From 3b63c5a73fb86d17bede0eaa87130b2446c41ef9 Mon Sep 17 00:00:00 2001
From: aiju <devnull@localhost>
Date: Sat, 9 Jun 2018 14:34:44 +0000
Subject: [PATCH] add ttfrender(1)

---
 sys/src/cmd/ttfrender.c | 173 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 173 insertions(+)
 create mode 100644 sys/src/cmd/ttfrender.c

diff --git a/sys/src/cmd/ttfrender.c b/sys/src/cmd/ttfrender.c
new file mode 100644
index 000000000..d4892f897
--- /dev/null
+++ b/sys/src/cmd/ttfrender.c
@@ -0,0 +1,173 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <draw.h>
+#include <ttf.h>
+#include <ctype.h>
+
+void
+elidenl(char **sp, int *np)
+{
+	char *s, *e, *t;
+	int nl;
+	
+	s = t = *sp;
+	e = *sp + *np;
+	for(; s < e; s++){
+		if(isspace(*s)){
+			nl = 0;
+			do
+				nl += *s == '\n';
+			while(++s < e && isspace(*s));
+			if(nl <= 1)
+				*t++ = ' ';
+			else while(nl-- > 0)
+				*t++ = '\n';
+			if(s == e) break;
+		}
+		*t++ = *s;
+	}
+}
+
+int
+readtext(char *fn, char **sp, int newline)
+{
+	int fd, n, a, rc;
+	char *s;
+	enum {B = 4096};
+	
+	fd = open(fn, OREAD);
+	if(fd < 0) sysfatal("open: %r");
+	s = nil;
+	n = 0;
+	a = 0;
+	for(;;){
+		if(n + B > a)
+			s = realloc(s, a += B);
+		if(s == nil) sysfatal("realloc: %r");
+		rc = read(fd, &s[n], B);
+		if(rc < 0) sysfatal("read: %r");
+		if(rc == 0) break;
+		n += rc;
+	}
+	if(newline)
+		elidenl(&s, &n);
+	s = realloc(s, n);
+	if(s == nil) sysfatal("realloc: %r");
+	*sp = s;
+	return n;
+}
+
+void
+usage(void)
+{
+	fprint(2, "usage: %s [ -lrjn ] [ -s scale ] [ -w width ] [ -h height ] [ -p ppem ] font [ text ]\n", argv0);
+	exits("usage");
+}
+
+int
+number(char *s)
+{
+	char *p;
+	int n;
+	
+	n = strtol(s, &p, 0);
+	if(p == s || *p != 0 || n <= 0)
+		usage();
+	return n;	
+}
+
+TTBitmap *
+scaledown(TTBitmap *b, int scale)
+{
+	TTBitmap *a;
+	int i, j;
+	
+	a = ttfnewbitmap(b->width / scale * 8, b->height / scale);
+	if(a == nil) sysfatal("ttfnewbitmap: %r");
+	for(j = 0; j < b->height; j++)
+		for(i = 0; i < b->width; i++){
+			if((b->bit[j * b->stride + (i>>3)] >> 7 - (i & 7) & 1) != 0)
+				a->bit[j/scale * a->stride + i/scale]++;
+			if(j % scale == scale - 1 && i % scale == scale - 1)
+				a->bit[j/scale * a->stride + i/scale] = ~((a->bit[j/scale * a->stride + i/scale] * 255 + scale * scale / 2) / (scale * scale));
+		}
+	return a;
+}
+
+void
+cropwrite(TTBitmap *b)
+{
+	int l, r, u, d, i;
+	
+	l = 0;
+	r = b->stride;
+	u = 0;
+	d = b->height;
+	for(; l < r; l++)
+		for(i = u; i < d; i++)
+			if(b->bit[i * b->stride + l] != 0xff)
+				goto right;
+right:
+	for(; l < r; r--)
+		for(i = u; i < d; i++)
+			if(b->bit[i * b->stride + r - 1] != 0xff)
+				goto up;
+up:
+	for(; u < d; u++)
+		for(i = l; i < r; i++)
+			if(b->bit[u * b->stride + i] != 0xff)
+				goto down;
+down:
+	for(; u < d; d--)
+		for(i = l; i < r; i++)
+			if(b->bit[(d - 1) * b->stride + i] != 0xff)
+				goto out;
+out:
+	print("%11s %11d %11d %11d %11d ", "k8", 0, 0, r - l, d - u);
+	for(i = u; i < d; i++)
+		write(1, b->bit + i * b->stride + l, r - l);
+
+}
+
+void
+main(int argc, char **argv)
+{
+	static int flags, scale, width, height, ppem, newline, crop;
+	char *font, *txtfn, *txt;
+	int txtn;
+	TTFont *f;
+	TTBitmap *b;
+	TTBitmap *d;
+
+	width = 640;
+	height = 480;
+	ppem = 18;
+	scale = 1;
+	ARGBEGIN {
+	case 'l': break;
+	case 'r': flags |= TTFRALIGN; break;
+	case 'c': flags |= TTFCENTER; break;
+	case 'j': flags |= TTFJUSTIFY; break;
+	case 'p': ppem = number(EARGF(usage())); break;
+	case 's': scale = number(EARGF(usage())); break;
+	case 'w': width = number(EARGF(usage())); break;
+	case 'h': height = number(EARGF(usage())); break;
+	case 'n': newline++; break;
+	case 'C': crop++; break;
+	} ARGEND;
+	if((uint)(argc - 1) > 1) usage();
+	font = argv[0];
+	txtfn = argc > 1 ? argv[1] : "/fd/0";
+	txtn = readtext(txtfn, &txt, newline);
+	f = ttfopen(font, ppem * scale, 0);
+	if(f == nil) sysfatal("ttfopen: %r");
+	b = ttfrender(f, txt, txt + txtn, width * scale, height * scale, flags, nil);
+	if(b == nil) sysfatal("ttfrender: %r");
+	d = scaledown(b, scale);
+	if(crop) cropwrite(d);
+	else{
+		print("%11s %11d %11d %11d %11d ", "k8", 0, 0, d->width/8, d->height);
+		write(1, d->bit, d->stride * d->height);
+	}
+}