Feature request: availability to change canvas size wile printing with the driver Postscript

[François Poulain]

2008/10/27 Ben Abbott <bpabbott at mac.com>:
> For on screen rendering (or for bitmaps), gnuplot does not explicitly
> control where its windows are displayed, so "position(1:2)" are moot.
> However, it is possible to tell gnuplot what the width, "position(3)", and
> height, "position(4)" are.
>
>        set term <terminal type> size <XX> <YY>

I am not so sure; it doesn't work on my gnuplot-4.2 :
gnuplot> set term wxt size 800 600
  Terminal type set to 'x11'
         undefined variable: size

(idem with wxt term)

> So, to review, my questions are;
>
> (1) How does gnuplot relate character width/height of the margins to
> points/inches/etc?
>
> (2) How does gnuplot determine on screen dpi?
>
> (3) How does gnuplot determine the dpi of bitmap output?

I don't know gnuplot, but a fast look in source code told me this is hardcoded:
~/gnuplot-4.2.2$ grep "dpi\|\ 640" src/* -R -C1
src/beos/GPBitmap.h-//int gX = 100, gY = 100;
src/beos/GPBitmap.h://unsigned int gW = 640, gH = 450;
src/beos/GPBitmap.h-
--
src/gplt_x11.c-static int gX = 100, gY = 100;
src/gplt_x11.c:static unsigned int gW = 640, gH = 450;
src/gplt_x11.c-static unsigned int gFlags = PSize;
--
src/NeXT/GnuView.h-						/* This is the coordinate system defined in
next.trm.				*/
src/NeXT/GnuView.h:#define NEXT_XMAX 640
src/NeXT/GnuView.h-#define NEXT_YMAX 480
--
src/term.c-
src/term.c:/* resolution in dpi for converting pixels to size units */
src/term.c-int gp_resolution = 72;
--
src/wxterminal/wxt_gui.cpp-			title.Printf(wxT("Gnuplot (window id :
%d)"), window.id);
src/wxterminal/wxt_gui.cpp:		window.frame = new wxtFrame( title,
window.id, 50, 50, 640, 480 );
src/wxterminal/wxt_gui.cpp-		window.frame->Show(true);

François

-- 
François Poulain <fpoulain at gmail.com>