vncv: implement autoscaling via -a flag (thanks unobe)

Add vncv option '-a' to autoscale remote frame buffer to
local screen window size; useful when remote frame buffer
is larger than the local screen.

If the remote frame buffer is larger than the local screen,
and autoscaling is disabled, only the upper left corner is
accessible.

5 files changed, 51 insertions, 12 deletions

diff --git a/sys/man/1/vnc b/sys/man/1/vnc
index 7ba8b1b49..5942eaa93 100644
--- a/sys/man/1/vnc
+++ b/sys/man/1/vnc
@@ -44,7 +44,7 @@ vncs, vncv \- remote frame buffer server and viewer for Virtual Network Computin
 .PP
 .B vncv
 [
-.B -cstv
+.B -acstv
 ]
 [
 .B -e
@@ -146,10 +146,14 @@ kills the VNC server running on display
 provides access to remote display
 .IB host : n \fR.
 It resizes its window to be the smaller of the
-remote frame buffer size and the local screen.
+remote frame buffer size and the local screen
+when not using the autoscaling option.
 .PP
 The options are:
 .TP
+.B -a
+autoscale remote frame buffer to local screen window size.
+.TP
 .B -c
 when connecting to 8-bit displays, request
 .B r4g4b4
@@ -166,7 +170,10 @@ The default (and full) set is
 .B corre
 .B hextile
 .B rre
-.BR raw .
+.B raw
+.B mousewarp
+.B desktopsize
+.BR xdesktopsize .
 The encodings should be given as a single space-separated argument
 (quoted when using the shell).
 .TP
@@ -199,7 +206,8 @@ print verbose output to standard error.
 .B http://www.uk.research.att.com/vnc
 .SH BUGS
 If the remote frame buffer is larger than the local screen,
-only the upper left corner can be accessed.
+and autoscaling is disabled, only the upper left corner can be accessed.
+Autoscaling is only implemented for raw encoding.
 .PP
 .I Vncs
 and
diff --git a/sys/src/cmd/vnc/draw.c b/sys/src/cmd/vnc/draw.c
index 61b2c1760..ed4a7f169 100644
--- a/sys/src/cmd/vnc/draw.c
+++ b/sys/src/cmd/vnc/draw.c
@@ -20,6 +20,16 @@ static	uchar	*linebuf;
 static	int	vpixb;
 static	int	pixb;
 static	void	(*pixcp)(uchar*, uchar*);
+static double scalex;
+static double scaley;
+
+static void
+vncsetscale(Vnc *v)
+{
+	scalex = (v->dim.max.x - v->dim.min.x) / (double)(screen->r.max.x - screen->r.min.x);
+	scaley = (v->dim.max.y - v->dim.min.y) / (double)(screen->r.max.y - screen->r.min.y);
+	if(verbose > 1) fprint(2, "scaling %fx%f\n", scalex, scaley);
+}
 
 static void
 vncsetdim(Vnc *v, Rectangle dim)
@@ -79,7 +89,7 @@ requestupdate(Vnc *v, int incremental)
 
 	lockdisplay(display);
 	flushimage(display, 1);
-	r = rectsubpt(screen->r, screen->r.min);
+	r = autoscale ? v->dim : rectsubpt(screen->r, screen->r.min);
 	unlockdisplay(display);
 	vnclock(v);
 	if(incremental == 0 && (v->canresize&2)!=0 && !eqrect(r, v->dim)){
@@ -94,7 +104,7 @@ requestupdate(Vnc *v, int incremental)
 	} else 
 		rectclip(&r, v->dim);
 	vncwrchar(v, MFrameReq);
-	vncwrchar(v, incremental);
+	vncwrchar(v, autoscale ? 0 : incremental);
 	vncwrrect(v, r);
 	vncflush(v);
 	vncunlock(v);
@@ -167,7 +177,8 @@ fillrect(Rectangle r, int stride, uchar *color)
 static void
 loadbuf(Vnc *v, Rectangle r, int stride)
 {
-	int off, y;
+	int off;
+	double x, y, endy;
 
 	if(cvtpixels){
 		y = r.min.y;
@@ -185,6 +196,12 @@ loadbuf(Vnc *v, Rectangle r, int stride)
 			off += stride;
 		}
 	}
+	if(autoscale){
+		endy = off/(double)stride;
+		for(y = 0; y < endy; y += scaley)
+			for(x = 0; x < stride; x+=scalex)
+				memmove(&pixbuf[(int)(y/scaley)*stride+(int)(x/scalex)/pixb*pixb], &pixbuf[(int)(y)*stride+(int)(x/pixb)*pixb], pixb);
+	}
 }
 
 static Rectangle
@@ -286,12 +303,15 @@ dorectangle(Vnc *v)
 
 	if(!rectinrect(r, v->dim))
 		sysfatal("bad rectangle from server: %R not in %R", r, v->dim);
-	maxr = rectsubpt(r, r.min);
+	maxr = autoscale ? rectsubpt(v->dim, v->dim.min) : rectsubpt( r, r.min );
+	maxr.max.x = Dx(maxr); maxr.min.x = 0;
+	maxr.max.y = Dy(maxr); maxr.min.y = 0;
 	stride = maxr.max.x * pixb;
+	if(verbose > 2) fprint(2, "maxr.max.x %d; maxr.max.y %d; maxr.min.x %d; maxr.min.y %d, pixb: %d, stride: %ld, type: %lx\n", maxr.max.x, maxr.max.y, maxr.min.x, maxr.min.y, pixb, stride, type);
 
 	switch(type){
 	default:
-		sysfatal("bad rectangle encoding from server");
+		sysfatal("bad rectangle encoding from server: %lx", type);
 		break;
 	case EncRaw:
 		loadbuf(v, maxr, stride);
@@ -399,6 +419,8 @@ readfromserver(Vnc *v)
 			sysfatal("bad message from server: %x", type);
 			break;
 		case MFrameUpdate:
+			if(autoscale)
+				vncsetscale(v);
 			vncrdchar(v);
 			n = vncrdshort(v);
 			while(n-- > 0)
diff --git a/sys/src/cmd/vnc/vncv.c b/sys/src/cmd/vnc/vncv.c
index 8633f9a2d..cea20a5bd 100644
--- a/sys/src/cmd/vnc/vncv.c
+++ b/sys/src/cmd/vnc/vncv.c
@@ -4,6 +4,7 @@
 
 char*		charset = "utf-8";
 char*		encodings = "copyrect hextile corre rre raw mousewarp desktopsize xdesktopsize";
+int		autoscale;
 int		bpp12;
 int		shared;
 int		verbose;
@@ -74,7 +75,7 @@ vnchungup(Vnc*)
 void
 usage(void)
 {
-	fprint(2, "usage: vncv [-e encodings] [-k keypattern] [-l charset] [-csv] host[:n]\n");
+	fprint(2, "usage: vncv [-acstv] [-e encodings] [-l charset] [-k keypattern] host[:n]\n");
 	exits("usage");
 }
 
@@ -87,6 +88,9 @@ main(int argc, char **argv)
 	keypattern = nil;
 	shared = 0;
 	ARGBEGIN{
+	case 'a':
+		autoscale = 1;
+		break;
 	case 'c':
 		bpp12 = 1;
 		break;
diff --git a/sys/src/cmd/vnc/vncv.h b/sys/src/cmd/vnc/vncv.h
index 564ef0b9c..e979b94a2 100644
--- a/sys/src/cmd/vnc/vncv.h
+++ b/sys/src/cmd/vnc/vncv.h
@@ -13,6 +13,7 @@ extern	uchar	zero[];
 /* vncv.c */
 extern	char		*charset;
 extern	char		*encodings;
+extern	int		autoscale;
 extern	int		bpp12;
 extern	Vnc*		vnc;
 extern	int		mousefd;
diff --git a/sys/src/cmd/vnc/wsys.c b/sys/src/cmd/vnc/wsys.c
index d4b13b655..984f91f6b 100644
--- a/sys/src/cmd/vnc/wsys.c
+++ b/sys/src/cmd/vnc/wsys.c
@@ -48,7 +48,7 @@ resized(int first)
 	if(getwindow(display, Refnone) < 0)
 		sysfatal("internal error: can't get the window image");
 	if((vnc->canresize&2) == 0)
-		adjustwin(vnc, first);
+		adjustwin(vnc, !autoscale && first);
 	unlockdisplay(display);
 	requestupdate(vnc, 0);
 }
@@ -154,8 +154,12 @@ readmouse(Vnc *v)
 			if(*start == 'm'){
 				m.xy.x = atoi(start+1);
 				m.xy.y = atoi(start+1+12);
-				m.buttons = atoi(start+1+2*12) & 0x1F;
 				m.xy = subpt(m.xy, screen->r.min);
+				if(autoscale){
+					m.xy.x *= (v->dim.max.x - v->dim.min.x) / (double)(screen->r.max.x - screen->r.min.x);
+					m.xy.y *= (v->dim.max.y - v->dim.min.y) / (double)(screen->r.max.y - screen->r.min.y);
+				}
+				m.buttons = atoi(start+1+2*12) & 0x1F;
 				if(ptinrect(m.xy, v->dim)){
 					mouseevent(v, m);
 					/* send wheel button *release* */