fontsrv: scaled pjw

R=rsc
https://codereview.appspot.com/6854130
diff --git a/src/cmd/fontsrv/a.h b/src/cmd/fontsrv/a.h
index 9f132e9..ffe46ae 100644
--- a/src/cmd/fontsrv/a.h
+++ b/src/cmd/fontsrv/a.h
@@ -25,3 +25,5 @@
 extern int nxfont;
 void *emalloc9p(ulong);
 extern Memsubfont *defont;
+
+void	drawpjw(Memimage*, Fontchar*, int, int, int, int);
diff --git a/src/cmd/fontsrv/mkfile b/src/cmd/fontsrv/mkfile
index fb3d86b..9fbbd52 100644
--- a/src/cmd/fontsrv/mkfile
+++ b/src/cmd/fontsrv/mkfile
@@ -8,8 +8,13 @@
 
 OFILES=\
 	main.$O\
+	pjw.$O\
 	$WSYSTYPE.$O\
 
 <$PLAN9/src/mkone
 
 osx-cocoa.$O: osx.c
+
+showpjw: showpjw.c
+	9c showpjw.c
+	9l -o showpjw showpjw.o
diff --git a/src/cmd/fontsrv/osx.c b/src/cmd/fontsrv/osx.c
index b00698a..f393dd3 100644
--- a/src/cmd/fontsrv/osx.c
+++ b/src/cmd/fontsrv/osx.c
@@ -241,18 +241,10 @@
 		if(g[0] == 0 || !CGFontGetGlyphBBoxes(font, g, n, r)) {
 		None:
 			fc->width = 0;
+			fc->left = 0;
 			if(i == 0) {
-				Point p;
-				Fontchar *i;
-				p = Pt(x, y0);
-				// memimagestring(m, p, memwhite, ZP, defont, peterface);
-				i = defont->info + 0;
-				memdraw(m, Rect(p.x+i->left, p.y+i->top, p.x+i->left+(i[1].x-i[0].x), p.y+i->bottom),
-					memwhite, ZP, defont->bits, Pt(i->x, i->top), S);
-				p.x += i->width;
-				fc->left = i->left;
-				fc->width = i->width;
-				x = p.x;
+				drawpjw(m, fc, x, (int)(bbox.size.width * size / unit + 0.99999999), y, y - y0);
+				x += fc->width;
 			}	
 			continue;
 		}
diff --git a/src/cmd/fontsrv/pjw.c b/src/cmd/fontsrv/pjw.c
new file mode 100644
index 0000000..30ebbed
--- /dev/null
+++ b/src/cmd/fontsrv/pjw.c
@@ -0,0 +1,321 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <memdraw.h>
+#include "a.h"
+
+uchar pjw[] = {
+  0x63, 0x6f, 0x6d, 0x70, 0x72, 0x65, 0x73, 0x73,
+  0x65, 0x64, 0x0a, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x20, 0x6b, 0x32, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x20, 0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x20, 0x20, 0x30, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x34, 0x38, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x20, 0x34, 0x38, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x34, 0x38, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
+  0x20, 0x20, 0x20, 0x35, 0x34, 0x31, 0x20, 0x80,
+  0xff, 0x20, 0x00, 0x08, 0x00, 0x82, 0xc0, 0x16,
+  0x7f, 0x04, 0x06, 0x04, 0x00, 0x83, 0xfc, 0x01,
+  0x04, 0x06, 0x04, 0x07, 0x04, 0x00, 0x83, 0xf1,
+  0x00, 0x50, 0x11, 0x04, 0x18, 0x04, 0x00, 0x84,
+  0xd4, 0x40, 0x48, 0x04, 0x05, 0x00, 0x07, 0x04,
+  0x00, 0x87, 0xc1, 0x44, 0x11, 0x04, 0x51, 0xbf,
+  0xff, 0xff, 0x04, 0x00, 0x87, 0x16, 0xfe, 0x81,
+  0x01, 0x40, 0x5f, 0xff, 0xff, 0x04, 0x00, 0x87,
+  0x5f, 0xff, 0xe4, 0x00, 0x40, 0x01, 0x1f, 0xff,
+  0x00, 0x00, 0x88, 0xfd, 0x7f, 0xff, 0xfd, 0x11,
+  0x11, 0x00, 0x3f, 0xff, 0x00, 0x00, 0x80, 0xe5,
+  0x00, 0x03, 0x84, 0x50, 0x04, 0x10, 0x42, 0xff,
+  0x00, 0x00, 0x80, 0x97, 0x00, 0x03, 0x84, 0x51,
+  0x00, 0x00, 0x07, 0xff, 0x00, 0x00, 0x80, 0x67,
+  0x00, 0x03, 0x84, 0xc4, 0x40, 0x41, 0x11, 0x3f,
+  0x00, 0x75, 0x80, 0x4f, 0x00, 0x0b, 0x84, 0xd0,
+  0x40, 0x00, 0x11, 0x1b, 0x82, 0xff, 0xff, 0xf5,
+  0x04, 0x40, 0x84, 0xf0, 0x00, 0x00, 0x04, 0x5f,
+  0x82, 0xff, 0xff, 0xe1, 0x04, 0x40, 0x84, 0xf4,
+  0x00, 0x00, 0x01, 0x5b, 0x00, 0x1e, 0x80, 0x2f,
+  0x04, 0x9e, 0x83, 0x00, 0x00, 0x00, 0x17, 0x82,
+  0xff, 0xff, 0x40, 0x04, 0x96, 0x84, 0xfe, 0x40,
+  0x00, 0x00, 0x0f, 0x82, 0xff, 0xfd, 0x00, 0x08,
+  0xa2, 0x00, 0x0b, 0x80, 0x5f, 0x8b, 0xff, 0xf9,
+  0x00, 0xb5, 0x11, 0x5f, 0xff, 0xa5, 0x64, 0x00,
+  0x00, 0x1f, 0x85, 0xff, 0xf4, 0x01, 0x0a, 0xf5,
+  0x42, 0x04, 0x2e, 0x81, 0x00, 0x2b, 0x87, 0xff,
+  0xf0, 0x01, 0x0f, 0xe4, 0x54, 0xf0, 0x3f, 0x00,
+  0x23, 0x80, 0x1f, 0x88, 0xff, 0xe0, 0x00, 0x4e,
+  0x00, 0x04, 0x00, 0x00, 0x14, 0x00, 0x0b, 0x85,
+  0xff, 0xd0, 0x00, 0x4c, 0x50, 0x44, 0x04, 0x22,
+  0x81, 0x00, 0x0b, 0x00, 0x0b, 0x82, 0x49, 0xa6,
+  0x6c, 0x00, 0x76, 0x00, 0x17, 0x00, 0x7d, 0x88,
+  0x5e, 0xd6, 0xf9, 0xf1, 0x51, 0x11, 0x00, 0x00,
+  0x3f, 0x88, 0xff, 0xf1, 0x02, 0x2e, 0xff, 0xf3,
+  0xf4, 0x6a, 0x98, 0x00, 0x0b, 0x8b, 0xff, 0xf3,
+  0x06, 0x2f, 0xff, 0xeb, 0xf8, 0xba, 0xa5, 0x04,
+  0x00, 0xbf, 0x8b, 0xff, 0xf5, 0x42, 0x9f, 0xff,
+  0xcf, 0xf9, 0x2b, 0xa5, 0xc0, 0x08, 0xff, 0x8b,
+  0xff, 0xfc, 0xc5, 0xfd, 0x40, 0x3f, 0xfe, 0x0b,
+  0xfb, 0x00, 0x0e, 0xff, 0x00, 0xae, 0x88, 0xfa,
+  0x96, 0xff, 0xfa, 0x81, 0x54, 0x40, 0x1b, 0xff,
+  0x00, 0x0b, 0x88, 0xfe, 0xaa, 0x96, 0x50, 0x59,
+  0x41, 0x00, 0x7b, 0xff, 0x88, 0xff, 0xff, 0x53,
+  0xff, 0xab, 0xc0, 0x00, 0x16, 0x54, 0x00, 0xba,
+  0x8b, 0xff, 0xff, 0x43, 0xfe, 0xaf, 0xe8, 0x00,
+  0x5a, 0x61, 0x41, 0xbf, 0xff, 0x8b, 0xff, 0xff,
+  0xc2, 0xfe, 0xbf, 0xfd, 0x01, 0x59, 0x94, 0x51,
+  0x1b, 0xff, 0x00, 0xef, 0x88, 0xfe, 0xeb, 0xed,
+  0x95, 0x56, 0x51, 0x40, 0x0f, 0xff, 0x8b, 0xff,
+  0xff, 0xe0, 0xfa, 0x92, 0xa6, 0x91, 0x11, 0x54,
+  0x54, 0x0f, 0xff, 0x00, 0x0b, 0x84, 0xff, 0xa9,
+  0xa4, 0x00, 0x01, 0x04, 0x17, 0x00, 0x6c, 0x88,
+  0xba, 0xaf, 0xff, 0xfd, 0x96, 0x45, 0x40, 0x3f,
+  0xff, 0x00, 0x00, 0x88, 0x2a, 0xbf, 0x6a, 0xa4,
+  0x15, 0x54, 0x60, 0xbf, 0xff, 0x00, 0x00, 0x88,
+  0xfa, 0xeb, 0x90, 0x00, 0x95, 0x41, 0xae, 0xff,
+  0xff, 0x04, 0x0b, 0x84, 0xaa, 0xa5, 0x11, 0x45,
+  0x05, 0x01, 0x49, 0x05, 0x27, 0x87, 0xae, 0xff,
+  0xf9, 0x54, 0x11, 0x6e, 0xff, 0xff, 0x0c, 0x0b,
+  0x85, 0xfa, 0x54, 0x56, 0xbb, 0xff, 0xff, 0x04,
+  0x0b, 0x87, 0xab, 0xbf, 0xf6, 0x54, 0x43, 0xaf,
+  0xff, 0xff, 0x04, 0x00, 0x87, 0x5a, 0xaa, 0x95,
+  0x11, 0x46, 0xfb, 0xff, 0xff, 0x04, 0x00, 0x84,
+  0xaa, 0x55, 0x10, 0x45, 0x07, 0x00, 0x17, 0x04,
+  0x00, 0x84, 0x95, 0x54, 0x45, 0x14, 0x06, 0x00,
+  0x5e, 0x04, 0x00, 0x87, 0xa5, 0x55, 0x50, 0x40,
+  0x12, 0xff, 0xbf, 0xff,
+};
+
+static Memimage* resample(int, int, Memimage*);
+
+void
+drawpjw(Memimage *m, Fontchar *fc, int x, int width, int height, int ascent)
+{
+	int w, p[2];
+	Memimage *pm, *pm1, *pm2;
+	Rectangle r;
+	int margin;
+	
+	w = width;
+
+	// assume margin below baseline is
+	// approximately how much room we should preserve at top above peter too
+	margin = height - ascent;
+	if(w > ascent-margin)
+		w = ascent-margin;
+
+	if(w < 9)
+		w = 9;
+	fc->width = w;
+
+	pipe(p);
+	write(p[1], pjw, sizeof pjw);
+	close(p[1]);
+	pm = readmemimage(p[0]);
+	close(p[0]);
+	if(pm == nil)
+		goto Error;
+	
+	pm1 = allocmemimage(pm->r, GREY8);
+	memimagedraw(pm1, pm1->r, pm, pm->r.min, nil, ZP, S);
+	pm2 = resample(w, w, pm1);
+	memimagedraw(m, Rect(x, ascent-w, x+w, ascent), memwhite, ZP, nil, ZP, SoverD);
+	memimagedraw(m, Rect(x, ascent-w, x+w, ascent), memblack, ZP, pm2, pm2->r.min, SoverD);
+	freememimage(pm2);
+	freememimage(pm1);
+	freememimage(pm);
+	return;
+
+Error:
+	// draw a box
+	r = Rect(x, 0, x+width, height);
+	memimagedraw(m, r, memwhite, ZP, nil, ZP, S);
+	memimagedraw(m, insetrect(r, 3), memblack, ZP, nil, ZP, S);
+	return;
+}
+
+#define K2 7	/* from -.7 to +.7 inclusive, meaning .2 into each adjacent pixel */
+#define NK (2*K2+1)
+static double K[NK];
+
+static void
+resamplex(uchar *in, int off, int d, int inx, uchar *out, int outx)
+{
+	int i, x, k;
+	double X, xx, v, rat;
+
+
+	rat = (double)inx/(double)outx;
+	for(x=0; x<outx; x++){
+		if(inx == outx){
+			/* don't resample if size unchanged */
+			out[off+x*d] = in[off+x*d];
+			continue;
+		}
+		v = 0.0;
+		X = x*rat;
+		for(k=-K2; k<=K2; k++){
+			xx = X + rat*k/10.;
+			i = xx;
+			if(i < 0)
+				i = 0;
+			if(i >= inx)
+				i = inx-1;
+			v += in[off+i*d] * K[K2+k];
+		}
+		out[off+x*d] = v;
+	}
+}
+
+static void
+resampley(uchar **in, int off, int iny, uchar **out, int outy)
+{
+	int y, i, k;
+	double Y, yy, v, rat;
+
+	rat = (double)iny/(double)outy;
+	for(y=0; y<outy; y++){
+		if(iny == outy){
+			/* don't resample if size unchanged */
+			out[y][off] = in[y][off];
+			continue;
+		}
+		v = 0.0;
+		Y = y*rat;
+		for(k=-K2; k<=K2; k++){
+			yy = Y + rat*k/10.;
+			i = yy;
+			if(i < 0)
+				i = 0;
+			if(i >= iny)
+				i = iny-1;
+			v += in[i][off] * K[K2+k];
+		}
+		out[y][off] = v;
+	}
+
+}
+
+static int
+max(int a, int b)
+{
+	if(a > b)
+		return a;
+	return b;
+}
+
+static double
+fac(int L)
+{
+	int i, f;
+
+	f = 1;
+	for(i=L; i>1; --i)
+		f *= i;
+	return f;
+}
+
+/* 
+ * i0(x) is the modified Bessel function, Σ (x/2)^2L / (L!)²
+ * There are faster ways to calculate this, but we precompute
+ * into a table so let's keep it simple.
+ */
+static double
+i0(double x)
+{
+	double v;
+	int L;
+
+	v = 1.0;
+	for(L=1; L<10; L++)
+		v += pow(x/2., 2*L)/pow(fac(L), 2);
+	return v;
+}
+
+static double
+kaiser(double x, double tau, double alpha)
+{
+	if(fabs(x) > tau)
+		return 0.;
+	return i0(alpha*sqrt(1-(x*x/(tau*tau))))/i0(alpha);
+}
+
+
+static Memimage*
+resample(int xsize, int ysize, Memimage *m)
+{
+	int i, j, bpl, nchan;
+	Memimage *new;
+	uchar **oscan, **nscan;
+	double v;
+
+	for(i=-K2; i<=K2; i++){
+		K[K2+i] = kaiser(i/10., K2/10., 4.);
+/*		print("%g %g\n", i/10., K[K2+i]); */
+	}
+
+	/* normalize */
+	v = 0.0;
+	for(i=0; i<NK; i++)
+		v += K[i];
+	for(i=0; i<NK; i++)
+		K[i] /= v;
+
+	new = allocmemimage(Rect(0, 0, xsize, ysize), m->chan);
+	if(new == nil)
+		sysfatal("can't allocate new image: %r");
+
+	oscan = malloc(Dy(m->r)*sizeof(uchar*));
+	nscan = malloc(max(ysize, Dy(m->r))*sizeof(uchar*));
+	if(oscan == nil || nscan == nil)
+		sysfatal("can't allocate: %r");
+
+	/* unload original image into scan lines */
+	bpl = bytesperline(m->r, m->depth);
+	for(i=0; i<Dy(m->r); i++){
+		oscan[i] = malloc(bpl);
+		if(oscan[i] == nil)
+			sysfatal("can't allocate: %r");
+		j = unloadmemimage(m, Rect(m->r.min.x, m->r.min.y+i, m->r.max.x, m->r.min.y+i+1), oscan[i], bpl);
+		if(j != bpl)
+			sysfatal("unloadmemimage");
+	}
+
+	/* allocate scan lines for destination. we do y first, so need at least Dy(m->r) lines */
+	bpl = bytesperline(Rect(0, 0, xsize, Dy(m->r)), m->depth);
+	for(i=0; i<max(ysize, Dy(m->r)); i++){
+		nscan[i] = malloc(bpl);
+		if(nscan[i] == nil)
+			sysfatal("can't allocate: %r");
+	}
+
+	/* resample in X */
+	nchan = m->depth/8;
+	for(i=0; i<Dy(m->r); i++){
+		for(j=0; j<nchan; j++){
+			if(j==0 && m->chan==XRGB32)
+				continue;
+			resamplex(oscan[i], j, nchan, Dx(m->r), nscan[i], xsize);
+		}
+		free(oscan[i]);
+		oscan[i] = nscan[i];
+		nscan[i] = malloc(bpl);
+		if(nscan[i] == nil)
+			sysfatal("can't allocate: %r");
+	}
+
+	/* resample in Y */
+	for(i=0; i<xsize; i++)
+		for(j=0; j<nchan; j++)
+			resampley(oscan, nchan*i+j, Dy(m->r), nscan, ysize);
+
+	/* pack data into destination */
+	bpl = bytesperline(new->r, m->depth);
+	for(i=0; i<ysize; i++){
+		j = loadmemimage(new, Rect(0, i, xsize, i+1), nscan[i], bpl);
+		if(j != bpl)
+			sysfatal("loadmemimage: %r");
+	}
+	return new;
+}
diff --git a/src/cmd/fontsrv/showpjw.c b/src/cmd/fontsrv/showpjw.c
new file mode 100644
index 0000000..65ab88f
--- /dev/null
+++ b/src/cmd/fontsrv/showpjw.c
@@ -0,0 +1,38 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <event.h>
+
+void eresized(int);
+
+void
+main(void)
+{
+	initdraw(nil, nil, nil);
+
+	einit(Emouse);
+	eresized(0);
+	for(;;)
+		emouse();
+}
+
+void
+eresized(int new)
+{
+	Point p;
+	int i;
+	char buf[100];
+
+	if(new && getwindow(display, Refnone) < 0)
+		sysfatal("getwindow: %r");
+
+	p = addpt(screen->r.min, Pt(10, 10));
+	draw(screen, screen->r, display->white, nil, ZP);
+	for(i=10; i<=50; i+=i/10) {
+		sprint(buf, "/mnt/font/LucidaGrande/%da/font", i);
+		font = openfont(display, buf);
+		string(screen, p, display->black, ZP, font, "Unknown char: \xe1\x88\xb4");
+		p.y += stringsize(font, "Unknown char: \xe1\x88\xb4").y;
+	}
+	flushimage(display, 1);
+}