gerbv(1)			 cvs-20051023			      gerbv(1)



NAME
       gerbv - Gerber Viewer

SYNOPSIS
       gerbv [OPTIONS] [gerberfile[s]]

DESCRIPTION
       gerbv is a viewer for Gerber files. Gerber files is generated from dif-
       ferent PCB CAD programs and are sent to subcontractors to actually make
       the PCB. gerbv also supports Excellon/NC drill files.


OPTIONS
       Warning!	  On  some platforms, which hasn’t long option available, only
       short options are available.


   gerbv Options
       -V|--version Prints the version number of gerbv and exits.

       -h|--help
	      Prints a brief usage guide.

       -l <filename>|--log=<filename>
	      All error messages etc are stored in a file with filename <file-
	      name>.

       -t <filename>|--tools=<filename>
	      Read Excellon tools from the file <filename>.

       --geometry=<width>x<height>[<+->x-position[<+->y-position]]
	      Sets  the	 the size of the window. X-position and y-position are
	      currently ignored by gerbv.

       -p <project filename>|--project=<project filename>
	      Load a stored project. Please note that the project file must be
	      stored in the same directory as the gerber files.


   GTK Options
       --gtk-module=MODULE Load an additional GTK module

       --g-fatal-warnings
	      Make all warnings fatal

       --gtk-debug=FLAGS
	      GTK debugging flags to set

       --gtk-no-debug=FLAGS
	      GTK debugging flags to unset

       --gdk-debug=FLAGS
	      GDK debugging flags to set

       --gdk-no-debug=FLAGS
	      GDK debugging flags to unset

       --display=DISPLAY
	      X display to use

       --sync Make X call synchronous

       --no-xshm
	      Don’t use X shared memory extension

       --name=NAME
	      Program name as used by the window manager

       --class=CLASS
	      Program class as used by the window manager


GENERAL
       When you start gerbv you can give the files to be loaded on the command
       line, either as each file separated with a space or by using wildcards.

       The user interface is graphical. Simply press left mouse button and the
       image will pan as you move the mouse. To	 manipulate  a	layer,	right-
       click on one of the rightmost buttons. That will bring up a pop-up menu
       where you can select what you want to do with that  layer  (load	 file,
       change color, etc).

       If  you	hold the mouse button over one the rightmost button a tooltips
       will show you the name of the file loaded on that layer.

       Default of concurrently loaded files are 20 layers. You can change this
       during configure with:

	./configure with-maxfiles=<number>


ACTIVATION AND DEACTIVATION OF LAYERS
       You can load several files at one time. You can then turn displaying of
       the layers on and off by clicking on one of the rightmost buttons.

       You can also control this from the keyboard. Press Alt, enter the  num-
       ber  on	the layer you want activate/deactivate on the numerical keypad
       and then release the Alt key.


ZOOMING
       Zooming can be handled by  either  menu	choices,  keypressing,	middle
       mouse  button  or scroll wheel. If you press Alt+I you will zoom in and
       if you press Alt+O you will zoom out.If you press middle	 mouse	button
       you  will  zoom out, and if you press Shift and middle mouse button you
       will zoom in.  Scroll wheel works if you enabled that in your X	server
       and mapped it to button 4 and 5. You can also zoom in by pressing z and
       zoom out by pressing shift+z (ie Z). You can  make  the	image  fit  by
       pressing f (there is also a menu alternativ for this).

       You  can	 also  do  zooming by outline. Press right mouse button, draw,
       release.	 The dashed line shows how the zooming will  be	 dependent  on
       the resolution of the window. The non-dashed outline will show what you
       actually selected. If you change your mind when started	to  mark  out-
       line,  you  can	always	abort  by pressing escape. By holding down the
       shift key when you press the right mouse button,	 you  will  select  an
       area  where  the point you started at will be the center of your selec-
       tion.


MEASUREMENTS
       You can do measurement on the image displayed. By pressing  shift,  the
       cursor  changes	to a plus. By using left mouse button you can draw the
       lines that you want to measure.	The result of the last measurement  is
       also  displayed	on the statusbar.  All measurements are in the drawing
       until you either zoom, pan or press the escape key.

       The statusbar shows the current mouse position on the layer in the same
       coordinates  as	in the file. Ie if you have (0,0) in the middle of the
       image in the gerber files, the statusbar will show (0,0)	 at  the  same
       place.


SUPERIMPOSING
       When  you  load	several	 Gerber files, you can display them "on top of
       each other", ie superimposing. The general way to display them are that
       upper  layers  cover  the  layers  beneath,  which is called copy (GTK+
       terms).

       The other ways selectable  are  and,  or,  xor  and  invert.  They  map
       directly	 to  corresponding functions in GTK. In GTK they are described
       as: "For colored images, only GDK_COPY, GDK_XOR and GDK_INVERT are gen-
       erally useful. For bitmaps, GDK_AND and GDK_OR are also useful."


PROJECTS
       gerbv  can  also	 handle projects. A project consist of bunch of loaded
       layers with their resp. color and the background color. The easiest way
       to  create  a  project is to load all files you want into the layer you
       want, set all the colors etc and do a "Save Project As...".

       You load a project either from the menu bar or by using the commandline
       switches -p or --project.

       Currently there is a limit in that the project file must be in the same
       directory as the gerber files to be loaded.


SCHEME
       The project files are simple Scheme programs that is interpreted	 by  a
       built  in  Scheme interpreter. The Scheme interpreter is TinyScheme and
       needs a Scheme program called init.scm to initialize itself. The search
       path	for	init.scm     is	    (in	    the	   following	order)
       /usr/local/gEDA-20060124/share/gerbv/scheme/share/gerbv/scheme/,	   the
       directory  with	the  executable gerbv, the directory gerbv was invoked
       from   and   finally   according	  to	the    environment    variable
       GERBV_SCHEMEINIT.


TOOLS FILE
       Not  every  Excellon  drill  file is self-sufficient. Some CADs produce
       .drd files where tools are only referenced, but never defined (such  as
       what diameter of the tool is.) Eagle CAD is one of such CADs, and there
       are more since many board houses require Tools files.

       A Tools file is a plain text file which you create in an	 editor.  Each
       line  of	 the  file  describes  one tool (the name and the diameter, in
       inches):

	    T01 0.024
	    T02 0.040
	    ...

       These are the same tools (T01 etc.) that are used in the Drill file.  A
       standard	 practice with Eagle is to create an empty Tools file, run the
       CAM processor, and the error report tells you which tools you "forgot".
       Then you put these tools into the file and rerun the CAM processor.

       You  load  a tool file by using the commandline switches -t or --tools.
       The file can have any name you wish, but Eagle expects the file type to
       be ".drl", so it makes sense to keep it this way. Some board houses are
       still using CAM software from DOS era, so you  may  want	 to  excercise
       caution before going beyond the 8.3 naming convention.

       When gerbv reads the Tools file it also checks that there are no dupli-
       cate definitions of tools. This does happen from time to	 time  as  you
       edit  the file by hand, especially if you, during design, add or remove
       parts from the board and then have to add  new  tools  into  the	 Tools
       file.  The  duplicate  tools  are  a very serious error which will stop
       (HOLD) your board until you fix the Tools file and maybe	 the  Excellon
       file.  gerbv  will detect duplicate tools if they are present, and will
       exit immediately to indicate such a fatal error in a very obvious  way.
       A message will also be printed to standard error.

       If your Excellon file does not contain tool definitions then gerbv will
       preconfigure the tools by deriving the diameter of the drill  bit  from
       the  tool  number. This is probably not what you want, and you will see
       warnings printed on the console.


ENVIRONMENT
       GERBV_SCHEMEINIT
	      Defines where the init.scm file is stored. Used by scheme inter-
	      preter, which is used by the project reader.


AUTHOR
       Stefan Petersen (spetm at users.sourceforge.net): Overall hacker and project leader
       Andreas Andersson (e92_aan at e.kth.se): Drill file support and general hacking
       Anders Eriksson (aenfaldor at users.sourceforge.net) : X and GTK+ ideas and hacking


COPYRIGHT
       Copyright ©  2001-2004 Stefan Petersen

       This document can be freely redistributed according to the terms of the
       GNU General Public License version 2.0



Version				 Feb 8th, 2004			      gerbv(1)