Explorer - Mosaic & Web/Explorer - Mosaic & Web.iso/helpers/ghostvew/src/gvc.doc

Text File | 1994-08-02 | 46.3 KB | 1,322 lines

1Overview
?Overview
W
 `GSview for Windows` is a graphical interface for MS-Windows `Ghostscript`.
P
 `PM GSview` is a graphical interface for OS/2 `Ghostscript`.
E
 Ghostscript is an interpreter for the PostScript page description language
 used by laser printers.
 For documents following the Adobe PostScript Document Structuring
 Conventions,
 GSview allows selected pages to be viewed or printed.
 GSview can be used with Ghostscript 3.0 or later.
 GSview was inspired by Tim Theisen's X11 Ghostview program.
2Installation
?Installation
 First you need to install Ghostscript 3.0.
 This version of GSview will not work with earlier versions of Ghostscript.

 Next install
P
 PM GSview by copying gvpm.exe and gvpm.hlp
W
 GSview for Windows by copying gsview.exe, gsview32.exe and gsview.hlp
E
 to your Ghostscript directory.

 Start GSview then select `Options` | `Ghostscript Command`,
 and enter the correct executable path and include path for Ghostscript.
 For example
P
   c:\gs\gsos2.exe -Ic:\gs;c:\psfonts
W
   c:\gs\gswin.exe -Ic:\gs;c:\gs\fonts
E

 It is essential that you get both the executable and the include path
 correct otherwise GSview will either complain that it cannot run
P
 gsos2,
W
 gswin,
E
 or it will start and then immediately exit with an
 error code.

 Set the environment variable TEMP to point to a directory for
 temporary files.  For example:
   SET TEMP=c:\temp
 The directory must exist and must be writeable.

 If you have some Type 1 fonts on your system, it may be possible to
 tell Ghostscript to use them.  See `Fontmap.os2` and `Fontmap.atm`
 supplied with Ghostscript for examples.

 If you have problems, try reading the help topic `Common Problems`.

 To uninstall GSview, remove the files you installed above, then remove
P
 c:\os2\gvpm.ini
W
 c:\windows\gsview.ini
E
 from the appropriate system directory.
2Document Structuring Conventions
?Document Structuring Conventions
?DSC
?Encapsulated PostScript
?EPSF
?EPS
 Adobe has defined a set of extended comment conventions that provide
 additional information about the page structure and resource
 requirements of a PostScript file.
 If a file contains these Document Structuring Convention (DSC) comments,
 GSview can display pages in random order using `Goto Page` and display pages
 in reverse order using `Previous Page`.  Selected pages can be extracted to
 another file or printed.

 If a file does not contain DSC comments, GSview can only
 display the pages in the original order.

 DSC conforming files start with the comment line:
  %!PS-Adobe-3.0
 where the number 3.0 may change and is the DSC version number.
 Some programs write PostScript files with a control-D as the first
 character of the file, followed by the comment line mentioned above.
 GSview will correctly report that these files are not DSC conforming,
 but will still display them with page selection features available.
 Complain to the author of the program that produced the PostScript file.
 To make the file DSC conforming, edit it to remove the control-D character.

 DSC conforming files contain lines such as:
  %%Pages: 24
  %%Page: 1 1
 These lines tell GSview how many pages a document contains and
 where they start.  GSview uses this information to select
 individual pages.

 Encapsulated PostScript Files (EPSF) are single page documents
 that contain a subset of the `DSC` comments and PostScript commands.
 EPS files start with the comment line:
  %!PS-Adobe-3.0 EPSF-3.0
 EPS files are commonly used for inclusion in other documents and
 for this reason require the bounding box comment:
   %%BoundingBox: llx lly urx ury
 where llx, lly, urx and ury are integers giving the x and y coordinates
 of the lower left and upper right corners of a bounding box which encloses
 all marks made on the page.

 Some EPS files contain a preview of the PostScript document.
 This preview can be a Windows Metafile, a TIFF file, or an Interchange
 preview (EPSI format).
 For the Windows Metafile or TIFF file preview, the EPS file under DOS
 contains a binary header which specifies the location and lengths of
 the preview and PostScript language sections of the EPS file.
 For the Interchange format, the preview is contained in DSC comments
 starting with
  %%BeginPreview: width height depth lines
 An EPS file with a preview can be created from an EPS file without a
 preview using `Add EPS Preview`.
2Opening a Document
?File
?Open
?Select File
?Close
 The `Open` command on the `File` menu opens a file and displays
 the first page.

 If the file contains `DSC` comments, pages can be selected using
 `Next Page`, `Previous Page` and `Goto Page`.

 If the file does not contain `DSC` comments, `Previous Page` and `Goto Page`
 will not work.  Another file should not be selected until a last page of
 the file has been displayed.

 When a file is open, GSview will display the document filename,
 the current page (if available) and while the cursor is over
 the image, the location of the cursor in coordinates specified
 by `Options` | `Units`.  The coordinate can be PostScript points
 (1/72"), millimetres or inches.
 The cursor location is useful for calculating bounding boxes.

 The `Select File` command is similar to `Open` but it does not display
 the document.
 This command is useful for opening a document prior to printing it.

 The `Close` command closes the currently open document.
 This should be used before the current file is changed by another
 program.
 If you do not do this and GSview detects that the file length or date
 have changed, it will close Ghostscript and rescan the document.

 See also `Print`.
2Page Selection
?Page Selection
?Next Page
?Previous Page
?Redisplay
?Goto Page
 `Next Page` moves to the next page of a document.
 This works even if the document does not contain `DSC` comments.

 `Previous Page` moves to the previous page.

 `Redisplay` redisplays the current page.

 `Goto Page` shows a dialog box which allows selection of the next page
 number to display.  The `Select Page` dialog box shows page labels
 since these are likely to be more useful than a sequential page number.

 The `Previous Page`, `Redisplay` and `Goto Page` commands work only if the
 document contains `DSC` comments.
2Zoom
?Zoom
 To enlarge a displayed feature, position the cross-hair mouse pointer
 over the feature then press the right mouse button.
 The window will swap from normal display resolution to zoom
 resolution and the status line will have the word `Zoomed` appended to it.
 The zoomed feature will be in the centre of the window.
 To cancel `Zoom`, press the right mouse button again or select
 any command that redraws the page (e.g. `Redisplay`, `Next Page`).
 By default the zoom resolution is 300 dots per inch but this can
 be changed with the `Media` | `Zoom Resolution` command.

 `Zoom` will only work for `DSC` conforming documents.
2Document Information
?Info
 A brief information area at the top of the window is used by
 GSview to display the document filename, the current page number
 and label (if available) and while the cursor is over the image, the
 location of the cursor in coordinates specified by `Options` | `Units`.
 The cursor location is useful for calculating bounding boxes.

 The `Info` command on the `File `menu shows a dialog box with the
 following information about the `DSC` comments in the current document.

 `File `is the full pathname to the document.

 `Type` is` DSC`,` EPS`, `No DSC comments` or 'Ignoring DSC Comments'.
 `EPS` is an Encapsulated PostScript File - a single page document
 that contains a subset of the `DSC` comments and PostScript commands.
 `EPS `files are commonly used for inclusion in other documents.
 `Ignoring DSC Comments` is displayed if `Options` | `Ignore DSC`
 is selected.

 `Title` is a text title that can be used when printing banner
 pages and for routing or recognising documents.

 `Date` is the time the document was created.

 `BoundingBox` specifies a box that encloses all the marks painted
 on the page.  The four integer values are the coordinates of the
 lower left and upper right corners of the bounding box in default
 user coordinates (1/72 inch).

 `Orientation `is either `Portrait `or` Landscape`.

 `Default Media` gives the media name followed by the width and
 height of that media in default user coordinates (1/72 inch).

 `Page Order` is either `Ascending`, `Descending` or `Special`

 `Pages` is the total number of pages in the document.

 `Page` gives the page label and page number.

 `Bitmap `is the size of the display bitmap in pixels which may be
 useful if you are copying the displayed image to the clipboard.
2Printing
?Print
?Print To File
?Print File
?Extract
 The `Print` command on the `File `menu allows printing of the document
 using Ghostscript.
 The Ghostscript printer driver and resolution are selected using the
 `Select Device` dialog box.   Pages are selected using the `Select Pages`
 dialog box.  The `All`, `Odd` and `Even` buttons provide quick selection
 of pages.

W
 The `mswinprn` printer driver uses the windows printer drivers
 and should work with any printer with raster capabilities.
 Printer resolution cannot be selected from within GSview; use
 the Control Panel instead.  This driver is very slow and should
 be considered a last resort if no other Ghostscript printer
 driver is available.

 With all other printer drivers, Ghostscript sends the output direct
 to the printer, without passing through a Windows printer driver.
 If you have trouble printing you may have to `Print To File`
 and then `Print File` or use the DOS command `COPY /B FILENAME PRN`.

 The Win32s versions of GSview and Ghostscript can't send output
 directly to a printer port so an attempt is made to pass the output
 unchanged through a Windows printer driver.  This does not work
 with some Windows printer drivers.  Use 'Print To File' if you
 have problems.
E

 This list of available devices and resolutions is stored in the
 [Devices] section of
W
 gsview.ini.
P
 gvpm.ini.
E
 The default list of devices and resolutions is taken from the
 standard distribution version of Ghostscript 3.0 and may not
 be complete.

 To print a document without displaying it, open the document
 using `Select File`.

 `Print To File` is similar to the `Print` command except that Ghostscript
 will write the output to a file instead of sending it to a printer.

 If you want to produce a bitmap, some useful drivers are
 `bmpmono`, `bmp16`, `bmp16m` and `bmp256`.

 `Print File` sends a file to a local port, bypassing the
W
 Windows
P
 Presentation Manager
E
 printer drivers.
 This is useful for sending a document to a PostScript printer,
 or for sending an output file produced by Ghostscript to a printer.

 `Extract` allows a range of pages to be copied from the current
 document to a new document.  For example, ten pages can be extracted
 from the middle of the current document and written to another file,
 which will later be sent to a printer.
3Properties
?Properties
 Some printer drivers allow extra properties to be specified.
 If two sections are added to the
W
 gsview.ini
P
 gvpm.ini
E
 file for these printer
 drivers, GSview will enable the `Properties` button which will
 display the `Edit Properties` dialog box.
 The following example shows how to add property information
 for the cdjcolor driver.
 First add a section which gives the current values.
 This section, after the first character is removed, gives the options
 that will appear in the `Property` list box.
 The first character is `s` for string or `d` for number.
  [cdjcolor]
  dBitsPerPixel=24
  dDepletion=1
  dShingling=2
  dBlackCorrect=4

 Next add a section which gives the values to display in the
 `Value` list box.
  [cdjcolor values]
  dBitsPerPixel=1,3,8,16,24
  dDepletion=1,2,3
  dShingling=0,1,2
  dBlackCorrect=0,1,2,3,4,5,6,7,8,9
 GSview will also add the value `[Not defined]` to the listbox.

 When you press the `OK` button in the `Edit Properties` dialog
 box, the current settings are written to the
W
 gsview.ini
P
 gvpm.ini
E
 file.

 When GSview prints a file, it will give Ghostscript the contents
 of the [cdjcolor] section of
W
 gsview.ini
P
 gvpm.ini
E
 as follows:
  -dBitsPerPixel=24 -dDepletion=1 -dShingling=2 -dBlackCorrect=3
 If the value of a property is `[Not defined]`, that property will
 not be sent to Ghostscript.

 Some entries for the cdj family of drivers are supplied in the
 property.ini file that comes with GSview.
3PS to EPS
?PS to EPS
 In general, it is not possible to convert a PostScript file to `EPS`.
 However, many single page PostScript files can be converted to `EPS`
 by changing the first line of the file to
  %!PS-Adobe-3.0 EPSF-3.0
 and then adding or fixing up the `%%BoundingBox` comment.

 `When used incorrectly, the PS to EPS command can produce PostScript
 files with incorrect DSC comments.  Such a document will cause problems
 when you try to include it inside another document.`

 To convert a PostScript file to `EPS`, the original file `must` be
 a `single page` document.  If the document contains `DSC` comments
 and is multi page, extract the desired page with `File` | `Extract`.
 If the document does not contain `DSC` comments, you will need to
 edit the file by hand to extract the desired page.

 `EPS` documents `must not` use any of the following operators:
  banddevice   clear         cleardictstack  copypage
  erasepage    exitserver    framedevice     grestoreall
  initclip     initgraphics  initmatrix      quit
  renderbands  setglobal     setpagedevice   setpageparams
  setshared    startjob      letter          note
  legal        a3            a4              a5

 The following operators should be used with care:
  nulldevice   setgstate     sethalftone    setmatrix
  setscreen    settransfer   setcolortransfer

 It is `your` responsibility to make sure that the above requirements
 are met.

 To test if a document contains any of the above operators, select
 `Options` | `EPS Warn` and then `Open` the desired document.
 After the page has been displayed, look in the Ghostscript text window.
 If any of the above operators have been used you should see lines like:
  Warning: EPS files must not use ...
 If you find these warnings then do `not` use `PS to EPS`.
 Remember to turn off `EPS Warn` afterwards.

 A document must be displayed before `PS to EPS` is used.
 The document must contain a `showpage`.
 This is required so that the bounding box can be measured.

 For documents without `DSC` comments, `PS to EPS` allows a bounding
 box to be specified, then writes out an `EPS` file consisting of
 an `EPS` wrapper around the original document.

 For documents with `DSC` comments, `PS to EPS` will change the
 first line of the file to
  %!PS-Adobe-3.0 EPSF-3.0
 then allows the `%%BoundingBox` comment to be changed or added.

 For `EPS` documents, `PS to EPS` allows the `%%BoundingBox` comment to
 be changed.

 `PS to EPS` does not clip the document to the `%%BoundingBox`.
 To do so would require changing the PostScript code itself.
 `PS to EPS` only changes the `DSC` comments.

 `PS to EPS` does not add a preview to a document.
 If you want a preview you add it with `Edit` | `Add EPS Preview` after
 first creating an `EPS` file with a correct `%%BoundingBox`.

 See also `Add EPS Preview`, `Extract`, `EPS Warn`.
2Text Extract and Find
?Text Extract and Find
?Text
?Text Extract
?Search
?Find
?Find Next
 In general, extracting text from a PostScript document is not a
 trivial operation.  Words may be broken.  Text may be encoded.
 Ligatures may be used (e.g replacing 'fi' with a single character).
 There may be no relationship between the location of a word in
 the PostScript file and its location on the page.

 However, it is common for PostScript documents to contain text in the
 same order as it appears on the page, and for it to be given in
 PostScript strings, surrounded by parentheses.  Complete lines
 may be given in one string, or one word per string.  For this sort
 of document, extracting text can be done with reasonable success.

 `Edit` | `Text Extract` will extract text contained in strings from
 specified pages and write it to a text file.
 Line breaks in this text file correspond to lines in the document.
 Spaces in the text file correspond to spaces within strings, or to
 separate strings.  A more effective method of extracting text is to
 use ps2ascii.ps supplied with Ghostscript.

 `Edit` | `Find` will search for text and display the first
 page that contains the text.  `Find` asks for a search text
 and a range of pages in which to search.
 The preceeding comments about extracting text from a PostScript
 document should be noted.  `Find` first extracts text from
 the document, then searches it ignoring all spaces in both the
 document and the search text.  Case is ignored when searching.
 Consequently the search text `these` would match both `These`
 and `The serial`.  No information is given about where the word
 is located on a given page because this information is not
 available without a complete PostScript interpreter.

 `Edit` | `Find Next` will continue the search from the next page.
2Clipboard
?Clipboard
?Edit
?Copy
?Paste To
?Convert Bitmap
?Bitmap
?Add EPS Preview
?Extract EPS
 The GSview window can be copied to the Clipboard as a bitmap
 by selecting `Copy` from the `Edit` menu.
W
 The bitmap may be a Device Independent Bitmap or it may be a Device
 Dependent Bitmap, depending on how Ghostscript was compiled.
 The default for Ghostscript 3.0 is a Device Independent Bitmap
 (BMP format).
E

 An alternative way to get a bitmap output from Ghostscript is
 to use one of the BMP drivers.  See `Print`.

W
 `Paste To` copies a Device Independent Bitmap from the Clipboard
 (if available) to a BMP file.

 `Convert Bitmap` converts between a Device Independent Bitmap and
 a Device Dependent Bitmap.
 If the clipboard contains a Device Independent Bitmap (BMP format),
 this is converted to a Device Dependent Bitmap and added to the clipboard.
 If the clipboard does not contain a colour palette, one is created
 from the Device Independent Bitmap and added to the clipboard.
 This option is present because some applications (notably Windows
 Paintbrush) won't recognise a Device Independent Bitmap in the clipboard.
P
 `Paste To` copies the currently displayed image (if available)
 to a BMP file.
E

 `Add EPS Preview` takes a bitmap from the
W
 clipboard
P
 display
E
 and uses it to add a preview to an EPS file.
 `Add EPS Preview` can create a DOS EPS file with a
W
 Windows Metafile or
E
 TIFF preview, or an EPSI file with an Interchange preview.
 To use the `Add EPS Preview` command the following steps must be followed.

 1. Make sure the document has a correct bounding box.
 A bounding box can be added or changed using `File` | `PS to EPS`.

 2. Select `Orientation` | `Portrait`.

 3. Select `Options` | `EPS Clip`.
 This will cause Ghostscript to use a display window the size of the
 bounding box instead of the page size.

 4. Select `Media` | `Resolution` and set a suitable resolution
 for the preview.  If the resolution is too high
W
 the bitmap may not fit in the clipboard, or will
P
 it
E
 make the EPS file excessively large.

 5. `Open` an EPS file that does not contain a preview.

W
 6. Select `Edit` | `Copy`.  This tells Ghostscript to copy the
 display bitmap to the Clipboard.  This allows GSview to access
 the bitmap in the next step.

 7.
P
 6.
E
 Select `Edit` | `Add EPS Preview`, then the preview format,
 then the new EPS filename.  GSview will write a new file containing
 the original PostScript EPS file and a preview created from the
W
 bitmap in the clipboard.
P
 display bitmap.
E
 The available preview formats are `Interchange`,
W
 `TIFF 4`, `TIFF 5` and `Windows Metafile`.
P
 `TIFF 4` and `TIFF 5`.
E
 If adding an Interchange preview, the document must have an `%%EndComments`
 line, otherwise GSview may put the preview in the wrong place.
 A TIFF 5 preview is a Class B image with no compression as described
 in Appendix G of the TIFF 5.0 memorandum.  A TIFF 4 preview is almost
 identical to the TIFF 5 preview, but avoids using tags which are not
 described in the TIFF 4 specifiation.
 WordPerfect 5.1 requires a TIFF 4 preview.

W
 8.
P
 7.
E
 Reset `Orientation` | `Portrait`, `Options` | `EPS Clip`
 and `Media` | `Resolution` to their previous values.

 To extract the PostScript or Preview section from a DOS EPS
 file, use `File` | `Select File` followed by `Edit` | `Extract EPS`
 then `PostScript` or `Preview`.

 See also `PS to EPS`.
2Options
?Options
 The `Options` menu has the following selections:
3Ghostscript Command
?Ghostscript Command
 The `Ghostscript Command` option allows selection of the command
 to use when executing Ghostscript.
 A default will be constructed using the GSview path and
 will look like:
W
  gswin -Ic:\gs;c:\gs\fonts
P
  gsos2.exe -Ic:\gs;c:\gs\fonts;c:\psfonts
E
 GSview will first attempt to find Ghostscript in the GSview
 directory and then will try the PATH.
 If GSview still cannot find Ghostscript, use this option to
 set the full pathname to Ghostscript.
 If you wish to specify that Ghostscript should look for its
 initialisation files in a different place, modify the -I option.
W
 Try to keep the command length short, otherwise GSview will
 have trouble printing files with Ghostscript.
E
 Only the Ghostscript EXE and include path may be specified -
 other items will confuse GSview.
3Sounds
?Sounds
 The `Sounds` option assigns sounds to various events.
 For each event the sound can be set to `None`, a `Speaker Beep` or
 a `Wave` file.

 You must have a sound driver loaded before using Wave files.
 Wave file sounds are not available under MS-Windows 3.0.

 The events are:

 `Output Page`: the PostScript showpage operator was executed.

 `No Page`: an invalid page was selected.
 For example, pressing `Prev` while on the first page of a document
 with `DSC` comments.

 `No Number`: a command required page numbering and the document did
 not have page numbering.
 For example, pressing `Goto Page` when viewing a document without
 `DSC` comments.

 `Not Open`:  a command required a document to be open and this was
 not the case.
 For example, pressing `Goto Page` when no document is open.

 `Error`: many types of errors.

 `Timeout`: no response from Ghostscript within a timeout period.
 For example, display snowflak.ps on a PC with a 286-12 CPU.

 `Start`: GSview opened.

 `Exit`: GSview closed.

 The defaults are for `No Page` and `Error` to be a `Speaker Beep`
 and all other events to be `None`.
3Units
?Units
 The `Units` option sets the units used to display the cursor location
 on the status bar.  Available units are PostScript points (`pt` = 1/72"),
 millimetres (`mm`) and inches (`in`).
 The default is `pt`.
3Save Settings
?Save Settings
?Settings
?INI file
?Save Settings on Exit
 The `Save Settings` option saves the GSview window position,
 window size, last used printer, last directory,
 `Sounds`, `Units`, `Save Last Directory`,
 `User Defined`, `Ghostscript Command`, `Button Bar`,
P
 `Fit Window To Page`,
E
 `Quick Open`, `Auto Redisplay`, `EPS Clip`, `EPS Warn`, `Ignore DSC`,
 `Depth`, `Orientation`, `Media`, `Resolution` and `Zoom Resolution`
 options to the initialisation file
W
 gsview.ini in the Windows system directory.
P
 gvpm.ini in the OS/2 system directory.
E
 GSview reads this file during startup.

 When the `Save Settings on Exit` option is checked, GSview will
 automatically save the above settings when you quit GSview.
3Safer
?Safer
 When the `Safer` option is `checked`, GSview will give Ghostscript
 the `-dSAFER` flag, which disables the deletefile and renamefile operators,
 and the ability to open files in any mode other than read-only.
 This is the default.

 When the `Safer` option is `unchecked` Ghostscript can change
 files.
3Save Last Directory
?Save Last Directory
 When the `Save Last Directory` option is `checked`, GSview will
 save the current directory when you quit GSview.  When GSview
 is started next, this will be made the current directory.
 This is the default.

 When `Save Last Directory` option is `unchecked`, the current
 directory when GSview is started will be the directory where
 GSview is located, or the working directory specified by
 the Program Manager.
3Button Bar
?Button Bar
?Magnify
 When the `Button Bar` option is `checked`, GSview will display
 a Button Bar down the left side of the window.  This is the default.
 The Button Bar contains the following items in order from top to
 bottom:

 `File` | `Open`

 `File` | `Print`

 `File` | `Info`

 `Help` | `Contents`

 `File` | `Goto Page`

 `File` | `Next Page`

 `File` | `Previous Page`

 `Go forward 5 pages`

 `Go back 5 pages`

 `Increase resolution by 1.2`

 `Decrease resolution by 1/1.2`

 `Edit` | `Find`

 `Edit` | `Find Next`

 If using the increase/decrease resolution buttons, `Auto Redisplay`
 should be set.  Instead of using these buttons, it is also possible
 to use the `Media` | `Resolution` command.
 When the `Button Bar` option is `unchecked`, GSview will not
 display the Button Bar.
P
3Fit Window To Page
?Fit Window To Page
 When the `Fit Window To Page` option is `checked`, GSview will
 shrink the window size so that it is no larger than the page
 being displayed.  This is the default.

 If `Fit Window To Page` is `unchecked`, GSview will not resize the
 window and areas outside the page will be drawn in light grey.
 This is useful if you do not wish the window to shrink when looking
 at pages at low resolution.
E
3Quick Open
?Quick Open
 When the `Quick Open` option is `checked`, GSview will not reload
 Ghostscript before every document, making opening of documents quicker.

 GSview tries to preserve the Ghostscript state between documents,
 but a document may still leave the Ghostscript interpreter in an unusual
 state or cause an error.  If an error occurs, Ghostscript will close.
 Error messages are displayed in the Ghostscript window.
 Select `Redisplay` to reopen the document.

 If `Quick Open` is `unchecked`, GSview will close Ghostscript and
 restart it before each new document or whenever the page orientation,
 resolution or size is changed.
3Auto Redisplay
?Auto Redisplay
 When the `Auto Redisplay` option is `checked`, GSview will
 redisplay `DSC` documents when the `Orientation`, `Resolution`,
 `Depth` or `Media` are changed.
 This is the default.

 If `Auto Redisplay` is `unchecked`, the `File` | `Redisplay` command
 must be used to redisplay a document after changing the
 `Orientation`, `Resolution`, `Depth` or `Media`.
3EPS Clip
?EPS Clip
 When the `EPS Clip` option is `checked`, GSview will clip the
 display bitmap to the bounding box of an EPS file instead of using the
 page size specified on the `Media` menu.  This is useful when
 adding a bitmap preview to an EPS file.

 If `EPS Clip` is `unchecked`, GSview will use the page size
 specified on the `Media` menu for EPS files.  This is the default.

 `EPS Clip` does not alter the original document, it only affects
 how much of the document is displayed by GSview.

 See also `Clipboard` | `Add EPS Preview`
3EPS Warn
?EPS Warn
 When the `EPS Warn` option is `checked`, GSview will write a
 prolog to Ghostscript when each file is opened.  This prolog will
 produce warning messages in the Ghostscript text window if any
 PostScript operators that should not be used in `EPS` files
 are used.  An example warning message is:
  Warning: EPS files must not use /initgraphics
 `EPS Warn` is not infallible.  It is possible to access restricted
 operators without `EPS Warn` producing a warning.

 The default for `EPS Warn` is `unchecked`.

 See also `PS to EPS`.
3Ignore DSC
?Ignore DSC
 Some documents incorrectly claim to conform to the Adobe Document
 Structuring Conventions.  Attempting to display one of these bogus
 documents will probably leave GSview horribly confused and unable
 to display the document.  If `Ignore DSC` is `checked`, GSview
 will treat the document as if it does not contain DSC comments
 and will only display the pages in the original order.

 The default for `Ignore DSC` is `unchecked`.
2Page Orientation
?Orientation
?Portrait
?Landscape
?Upside-down
?Seascape
?Swap Landscape
 The `Portrait`, `Landscape`, `Upside-down` and `Seascape`
 (reverse Landscape) commands on the `Orientation `Menu select
 the page orientation used by the display.
 `Landscape` implies a clockwise rotation of the paper by 90 degrees.
 `Seascape` implies an anti-clockwise rotation of the paper by 90 degrees.
 These orientation options only affect the display and do not affect
 the print commands.
 If a `DSC` page orientation comment is found, the orientation will be
 selected automatically.

 When the `Swap Landscape` option is `checked`, GSview swaps the
 meaning of Landscape and Seascape.
 Most of the Landscape documents that I have encountered require a 90
 clockwise rotation of the paper to view.
 However, there is no standard and some documents need to be rotated
 the other way.
 The `Swap Landscape` button allows GSview to automatically rotate the
 document the right way in response to the `%%Orientation` comment in the
 PostScript file.

 See also `Page Size and Display Resolution`.
2Page Size and Display Resolution
?Page Size and Display Resolution
?Resolution
?Zoom Resolution
?Depth
?Page Size
?Media
?User Defined
 The `Resolution` command on the `Media` menu selects the display
 resolution in dots per inch.
 The default for a VGA display is 96 dots per inch.

 For DSC conforming files, pressing the right mouse button will
 zoom into the page at what is usually printer resolution.
 Pressing the right mouse button a second time will zoom back out to
 normal display resolution.
 The `Zoom Resolution` command on the `Media` menu sets the zoom
 resolution in dots per inch.

 The `Depth` sub menu on the `Media` menu selects the display
 depth in bits per pixels.

 The `Media` menu also allows selection of page size.
 Available page sizes are:
  Letter          8.5 x 11   inch
  Tabloid        11   x 17   inch
  Ledger         17   x 11   inch
  Legal           8.5 x 14   inch
  Statement       5.5 x  8.5 inch
  Executive       7.5 x 10   inch
  A3              297 x 420  mm
  A4              210 x 297  mm
  A5              148 x 210  mm
  B4              257 x 364  mm
  B5              182 x 257  mm
  Folio           8.5 x 13   inch
  Quarto          8.5 x 10.8 inch
  10x14          10   x 14   inch

 A user defined size can be specified in PostScript points (1/72 inch)
 with the `User Defined` command.  A size of 480x360 points at 96 dpi
 will give an image size of 640x480 pixels.

 If a `DSC` media comment is found, the page type will be selected
 automatically.  If the media specification is not one of the above
 page types, the `User Defined` size will be set.
2Keys
?Keys
 Following are the key assignments for GSview.

 `O`, `o`  Open and display a file.  (`File` | `Open`)

 `C`, `c`  Close file.  (`File` | `Close`)

 `N`, `n`, `+`  Next Page.  (`File` | `Next Page`)

 `V`, `v`, `-`  Previous Page.  (`File` | `Previous Page`)

 `G`, `g`  Goto Page.  (`File` | `Goto Page`)

 `I`, `i`  File information.  (`File` | `Info`)

 `R`, `r`  Redisplay page.  (`File` | `Redisplay`)

 `S`, `s`  Select file: open but don't display.  (`File` | `Select File`)

 `P`, `p`  Print all or some pages to a printer.  (`File` | `Print`)

 `F`, `f`  Print all or some pages to a File.  (`File` | `Print To File`)

 `E`, `e`  Extract some pages to another File.  (`File` | `Extract`)

 `F1`  Help.  (`Help` | `Contents`)

 `Ctrl+C`, `Insert`  Copy displayed bitmap to clipboard.  (`Edit` | `Copy`)

W
 `Up`  Scroll up 16 pixels.

 `Down`  Scroll down 16 pixels.

 `Left`  Scroll left one screen.

 `Right`  Scroll right one screen.
P
 `Arrow Keys`  Scroll by 16 pixels.

 `Ctrl+Left`  Scroll left one screen.

 `Ctrl+Right`  Scroll right one screen.
E

 `Page Up`  Scroll up one screen (window height).

 `Page Down`  Scroll down one screen.

 `Home`  Scroll to top of page.

 `End`  Scroll to bottom of page.
W
2Running GSview from the File Manager
?Registration Info Editor
?File Manager
 To run GSview when a PostScript file is double clicked in the
 File Manager, the following sequence must be followed to teach
 File Manager about PostScript files.

 From the `Program Manager`, run the Registration Info Editor using
 `File `| `Run...` then type `regedit`.
 From the `Registration Info Editor` select `Edit `| `Add File Type...`
 then enter the following fields:
  Identifier = psfile
  Filetype = PostScript
  Action = Open
  Command = gsview %1
  Uses DDE = unchecked
  Action = Print
  Command = gsview /p %1
  Uses DDE = unchecked
 Then press `OK`.

 From the `File Manager`, select `File `| `Associate` then
 enter the following fields:
  Files with Extension = ps
  Associate With = PostScript (gsview)
 Then press `OK`.

 Put gsview.exe and gsview.hlp in a directory on your PATH.
 That's it!  Now when you double click on a PostScript file,
 the `File Manager` will run GSview.  When you drop a PostScript
 file on the `Print Manager`, GSview will print the file.
E
2Command line options
?Command line options
 Usage:
W
  gsview [/D] filename
  gsview [/D] /F filename
  gsview [/D] /P filename
  gsview [/D] /S[port] filename
P
  gvpm [/D] filename
  gvpm [/D] /F filename
  gvpm [/D] /P filename
E

 To start GSview and display filename.ps use:
W
  gsview filename.ps
P
  gvpm filename.ps
E
 To start GSview and print filename.ps using Ghostscript
 (`File` | `Print`) use:
W
  gsview /P filename.ps
P
  gvpm /P filename.ps
E
 To start GSview and print filename.ps to a file using Ghostscript
 (`File` | `Print To File`) use:
W
  gsview /F filename.ps
P
  gvpm /F filename.ps
E
W
 To start GSview and spool filename.ps for printing directly to
 a printer (`File` | `Print File`) use:
  gsview /S filename.ps
 To start GSview and spool filename.ps for printing directly to
 printer port LPT3: use:
  gsview /SLPT3: filename.ps
E

 To start GSview in debug mode use:
W
  gsview /D
P
  gvpm /D
E
 In debug mode GSview will `not` remove its temporary files.
 This is to allow inspection of these files after GSview has finished.

 GSview ignores the case of option:
 /p is the same as /P.
2Copyright
?Copyright
 The `About` menu item shows the GSview copyright message
 and GSview version number.

W
  GSVIEW.EXE - A Ghostscript graphical interface
P
  GVPM.EXE - A Ghostscript graphical interface
E
  Copyright (C) 1993, 1994, Russell Lang.  All rights reserved.

 This file is part of GSview.

 This program is distributed with NO WARRANTY OF ANY KIND.  No author
 or distributor accepts any responsibility for the consequences of using it,
 or for whether it serves any particular purpose or works at all, unless he
 or she says so in writing.  Refer to the GSview Free Public Licence
 (the "Licence") for full details.

 Every copy of GSview must include a copy of the Licence, normally in a
 plain ASCII text file named LICENCE.  The Licence grants you the right
 to copy, modify and redistribute GSview, but only under certain conditions
 described in the Licence.  Among other things, the Licence requires that
 the copyright notice and this notice be preserved on all copies.

     Author: Russell Lang
   Internet: [e-mail]
2Common Problems
?Common Problems
?Problems
W
 `Problem:` Can't run gswin...

 GSview requires Ghostscript for Windows (gswin.exe).
 This error message usually occurs if you don't have Ghostscript
 for Windows, or if GSview can't find Ghostscript for Windows.

 From the GSview menu select `Options` | `Ghostscript Command`
 and enter the correct executable path and include path for Ghostscript.
 For example:
  c:\gs\gswin.exe -Ic:\gs

 You must set the include path for Ghostscript using either the
 `-I` command or the `GS_LIB` environment variable.

 Make sure you don't already have Windows Ghostscript running.
 Only one copy of Windows Ghostscript can be running at a time.
 Only one copy of GSview can be running at a time.
P
 `Problem:` Can't run gsos2...

 GSview requires OS/2 Ghostscript (gsos2.exe).
 This error message occurs if you don't have OS/2 Ghostscript,
 or if GSview can't find OS/2 Ghostscript.

 From the GSview menu select `Options` | `Ghostscript Command`
 and enter the correct executable path and include path for Ghostscript.
 For example:
  c:\gs\gsos2.exe -Ic:\gs;c:\gs\fonts;c:\psfonts

 You must set the include path for Ghostscript using either the
 `-I` command or the `GS_LIB` environment variable.
E

 `Problem:` Ghostscript starts and then immediately exits with error code 1.

W
 Read the error message in the Ghostscript window before pressing
 OK in the message box.

E
 Ghostscript probably couldn't find its initialisation files.
 Set the Ghostscript include path by adding `-Idirectory` to the
 command in `Options` | `Ghostscript Command`, where `directory`
 includes the name of the directory that contains the Ghostscript
 initialisation files,
 Alternatively, set the environment variable GS_LIB.

 Read the file use.doc that comes with Ghostscript.

W
 Alternatively, you may be using an incompatible version of Ghostscript.
 This version of GSview requires Ghostscript version `3.0` or later.
 If you are using an incompatible version of Ghostscript, the
 Ghostscript text window will show one of the following error messages
  undefined in ear
  undefined in XXclear
 where `XX` are a pair of garbage characters.

 `Problem:` Message Box says `Incompatible Windows Ghostscript`

 You probably have an earlier version of Ghostscript.
 Make sure you have Ghostscript version 3.0 or later.

 `Problem:` GSview says 'Drawing...' or 'Printing...' and shows an
 hourglass cursor.  When the cursor is moved off the GSview window
 it changes to a normal arrow.

 The above state is normal while GSview is waiting for Ghostscript
 to do something.  It may be that the document is very complex and
 Ghostscript is just taking a long time.  In this state it is safe to
 resize or scroll the window, but do not select any menu commands.

 If this is not the case then GSview probably got no response
 from Ghostscript.
 Open the Ghostscript text window and look at any error messages.
 Close Ghostscript using the Ghostscript system menu.
 If GSview is still waiting, press the GSview Open button
 (even though the cursor is still an hourglass).
 Press the 'Yes' button on the 'gsview is busy' message box.
 GSview should then revert to the non-waiting mode.

 `Problem:` Ghostscript displays a "Pipe error" message box.

 GSview could not open a temporary file.  GSview requires a temporary
 file for `piping` commands to Ghostscript.  This temporary file is
 created in the directory given by the environment variable TEMP,
 or if that is not set, in the current directory.
 `Pipe error` will result when

 1. TEMP is not set and the current directory is read-only.
 For example, the current directory is on a CD-ROM or a network.

 Solution:  Set TEMP environment variable in AUTOEXEC.BAT.

 2. TEMP is set but does not point to a valid read-write directory.

 Solution: Change TEMP to point to a directory that exists
 and is read-write.

 3. Disk is full.
E

 `Problem:` GSview says that a multipage PostScript file produced
 by MS-Windows contains 0 pages and will only show the first page.

 This is because the document does not have correct DSC comments.
 From the Control Panel, select `Printers`, `Options...`, then in the
 `Print to` group box click on the `Printer` radio button.  You cannot
 use the `Print To` `Encapsulated PostScript File` for printing
 multipage files.  The correct method is to connect the printer
 to `FILE:`.
 In addition,
 from the Control Panel select `Printers`, `Options...`, `Advanced` and
 then check `Conform to Adobe Document Structuring Convention`.

 The DSC comment `%%Pages: 0` means that the document does not produce
 any pages.  That is, the PostScript `showpage` operator is not used.
 If you find a PostScript document that has multiple pages and contains
 the `%%Pages: 0` comment, change the first line from `%!PS-Adobe-` to `%!`.
 GSview will then ignore the DSC comments and allow you to view all
 pages, but only in the original order.  Complain to the author of the
 program that produced that PostScript file.

 `Problem:` PostScript files produced by MS-Windows start with a Control-D.

 Since this occurs even when the PostScript printer
 `Conform to Document Structuring Convention`
 checkbox is checked, this must be considered a
 bug in the MS-Windows PostScript printer driver.
 The bug fix is documented in the MS-Windows PRINTERS.WRI file.
 Edit the win.ini file and search for the PostScript printer section.
 There may be more than one.  In each of these sections add
 `CTRLD=0` as shown below.

  [Apple LaserWriter II NT,FILE]
  CTRLD=0

 `Problem:` PostScript files produced by Word for Windows 6.0
 cause a "Missing %%Pages comment" message box.

 Congratulations.  You have just found a mistake in the DSC comments
 when Word included an EPS file.  Word should have surrounded the
 included EPS file with the lines
  %%BeginDocument: filename.eps
  %%EndDocument
 Because Word didn't do this, GSview can't tell how many pages
 are in the document and where they are located.

 Please complain to Microsoft.  There is a problem in the EPSIMP.FLT
 filter version 2.01 which Microsoft needs to fix.

 In the interim, you have two solutions:

 1. Select `Options` | `Ignore DSC`

 2. Edit the PostScript file to correct the DSC comments.
 Search the PostScript file for all lines containing
   %MSEPS Preamble
 From each of these lines, search forward for the start of the
 included EPS file which should start with a line like
  %%PS-Adobe-3.0 EPSF-3.0
 Above these lines add the line
  %%BeginDocument: AddedByHand

 Then search for all lines containing
  %MSEPS Trailer
 Above these lines add the line
  %%EndDocument

 GSview should then be able to display the file correctly.

 `Problem:` Ghostscript always outputs to a printer instead of the
 GSview window.

 You must not use the GS_DEVICE environment variable.
W

 `Problem:` Ghostscript displays a message box "pipe overflow".

 The document may contain incorrect DSC comments.

 You must wait until Ghostscript is not busy before attempting to
 display another page.  Exit and then restart GSview.
E
2Internals
?Internals
W
 The preferred method for driving Ghostscript would be to start it
 as a child process and then to send it PostScript code through a pipe.
 Windows 3.1 supports neither child processes nor pipes.

 GSview interacts with Ghostscript by sending messages between
 the GSview and Ghostscript windows.
 GSview creates an imitation pipe to Ghostscript by writing
 into a shareable global memory block and then passing the handle
 to Ghostscript.

 GSview starts Ghostscript for displaying using
  gswin -dBitsPerPixel=x -dSAFER -rXDPIxYDPI -gWIDTHxHEIGHT -sGSVIEW=xxxx -
 where xxxx is the handle to the GSview window.
 Ghostscript then tells GSview the handle to the text window by sending
 a message WM_USER with wParam HWND_TEXT=0 to the GSview window.
 Instead of creating another window for the image, Ghostscript
 creates a child window of the GSview window for displaying
 the bitmap. Ghostscript tells GSview the handle to this child
 image window by sending a message WM_USER with wParam
 HWND_IMGCHILD=1.

 Ghostscript also sends WM_USER messages to GSview with wParam
 GSWIN_CLOSE=2 when it is exiting,
 SYNC_OUTPUT=3 when the image needs to be redrawn (win_sync_output),
 OUTPUT_PAGE=4 when a page is to be output (win_output_page),
 SCROLL_POSITION=5 when the window is scrolled,
 PIPE_DATA=6 for passing the handle to a global memory block (in
 lParam) for the imitation pipe,
 BEGIN=7 when "-1 false .outputpage" is executed and
 END=8 when "-2 false .outputpage" is executed.

 When Ghostscript sends the OUTPUT_PAGE command it waits until it
 receives a NEXT_PAGE command from GSview.

 GSview sends WM_USER messages to the Ghostscript Image window with
 wParam NEXT_PAGE=10 when it is time to move to the next page and
 COPY_CLIPBOARD=11 when the bitmap should be copied to the clipboard.
 GSview sends WM_USER messages to the Ghostscript Text window with
 wParam PIPE_REQUEST=12 when it wants more pipe data.

 GSview uses temporary files of the name gsviewXX.XXX in the
 directory given by the TEMP environment variable.
 Keep TEMP short to avoid the gswin command line exceeding 128 characters.

 GSview starts Ghostscript for printing using
  gswin -sGSVIEW=xxxx @optfile
 optfile contains
  -dNOPAUSE
  -dSAFER
  -sDEVICE=devname
  -rXDPIxYDPI
  -gWIDTHxHEIGHT
  -sOutputFile=outfilename
  filename.ps
  quit.ps

P
 GSview starts Ghostscript for displaying using
  gsos2 -dBitsPerPixel=x -dSAFER -rXDPIxYDPI -gWIDTHxHEIGHT -sGSVIEW=xxxx -
 where xxxx is a string used to access a named shareable memory block,
 two semaphores and a queue.  These are listed in gdevpm.h.
 The shareable memory block contains a bitmap in BMP format.
 The SYNC semaphore is not used (it is used by gspmdrv.exe instead).
 The NEXT semaphore is used when waiting at each showpage.
 The MUTEX is used to sychronise access to the bitmap.
 The QUEUE is used by Ghostscript to notify GSview about the
 following significant events:  1. Starting to draw into bitmap,
 2. Synchronise (redraw) page, 3. showpage (redraw page),
 4. Ghostscript is closing, 5. Ghostscript fatal error,
 6. Palette in bitmap has changed,
 7. "-1 false .outputpage" is executed,
 8. "-2 false .outputpage" is executed.
 PostScript code is piped to the Ghostscript stdin.
 Ghostscript stdout goes to a window.

 GSview uses temporary files of the name gvXXXXXX in the
 directory given by the TEMP environment variable.

 GSview starts Ghostscript for printing using
  gsos2 @optfile
 optfile contains
  -dNOPAUSE
  -dSAFER
  -sDEVICE=devname
  -rXDPIxYDPI
  -gWIDTHxHEIGHT
  -sOutputFile=outfilename
  filename.ps
  quit.ps

E