history2.htm

GhostScript的源代码

Makes StandardEncoding and ISOLatin1Encoding arrays, rather than packed
arrays, on large-memory systems, for compatibility with certain test
suites.  Changes .registerencoding to accept arrays as well as packed
arrays.

<h2><a name="V2.9.4b_Library"></a>Library</h2>

Fixes bugs:
	- Due to an error in cie_mult3, CIE-based colors were badly
mis-mapped.
*	- Very narrow (but not empty) rectangles would disappear.
*	- Small halftone cells could smash the next higher entry in the
halftone cache.
	- The orientation algorithm in gxstroke.c still interchanged
clockwise and counter-clockwise coordinate systems (after having been
"fixed" at least 3 times).
	- Stroking 1-pixel-wide lines shortened them, instead of
lengthening them, if non-butt caps were requested.

Refactors mem_mapped8_copy_mono because of limitations in the bcc32
compiler.

<h1><a name="Version2.9.3b"></a>Version 2.9.3-beta (1/19/94)</h1>

This version was created for evaluation purposes for a few users who
needed Level 2 capability; it was never released to anyone else, even
beta testers.

<h2><a name="V2.9.3b_Documentation"></a>Documentation</h2>

Fixes bugs:
	- The description of psview and xpsview was incorrect.

<h2><a name="V2.9.3b_Procedures"></a>Procedures</h2>

Changes the installation directories for Unix and similar systems to put
Ghostscript data in $(datadir)/ghostscript/gs-NN.NN.NN rather than directly
in $(datadir)/ghostscript.  (Fonts still go in $(datadir)/ghostscript/fonts.)

<h2><a name="V2.9.3b_Drivers"></a>Drivers</h2>

Fixes bugs:
	- Some spaces were incorrectly replaced with tabs in the help
message in the 3B1 display driver.
	- The BMP driver wrote a spurious scan line at the beginning
of its output.
	- The monochrome PCX driver had the two palette elements
interchanged.

Adds new drivers:
	- A user-contributed driver for the Xerox XES printer format.  This
has a FSF copyright.
	- A user-contributed driver for the Epson AP3250 printer.  (This is
the same as the Stylus 800, with slightly different margins.)
	- A user-contributed driver for the DEC LA70 printer with some
algorithms for improving text at low resolutions.  This has a FSF
copyright.
	- A user-contributed driver for an intermediate-resolution mode
for 9-pin "Epson-compatible" printers.

Changes the name of the Stylus 800 driver from escp2 to st800.

Adds a compile-time flag to the Epson driver to cope with Panasonic 9-pin
printers, which sometimes have trouble mixing graphics and tabs.

<h2><a name="V2.9.3b_Platforms"></a>Platforms</h2>

Fixes bugs:
	- The MS Windows driver (gp_mswin.c) referred to iodev.h rather
than gxiodev.h.
	- On Unix System V platforms, gp_unifs.c and gdevpipe.c were
incorrectly omitted from the link list.
	- (Some?) System V platforms don't have the S_ISDIR macro,
requiring a change in stat_.h.
	- The Unix `install' target didn't install gs_std_e.ps and
gs_iso_e.ps.
	- No MODULES.LIS file was provided for VMS.

Adds Desqview/X makefiles that actually work.

Documents the set of H-P-supplied patches needed to make H-P's
compilers process Ghostscript.

Changes the MS Windows driver so that if the user presses the Enter key
while the image window has the focus, the text window will be brought to
the top and made the active window.  This is useful when viewing a
multi-page document with Ghostscript.

<h2><a name="V2.9.3b_Interpreter"></a>Interpreter</h2>

Fixes bugs:
	- The definition of public_st_client_color() in gxccolor.h
included an extraneous semicolon.
	- The definition of private_st_AXD_state() in sfilter.h included an
extraneous semicolon.
	- saxx.c didn't include sfilter.h, which it needed for the
definition of private_st_AXD_state().
	- ialloc_struct failed to create a separate chunk if the structure
was very large.
	- setcolorspace didn't allocate the colorspace object in the same
VM space as the graphics state, causing problems when the colorspace was
freed.
	- In rare circumstances, currentfile could return an empty array
rather than a file.
	- Dictionary keys were always allocated in global VM.
	- If NOPLATFONTS was true, definefont didn't check whether the
dictionary was read-only before trying to insert an ExactSize key.
	- startjob could get an invalidaccess error, because serverdict was
allocated in global VM.
	- Using definefont with an already registered font created a
circular list structure.
	- If a PostScript procedure appeared as a CharString in a Type 1
font, it was always called with the character name, never the character
code.
	- The SubFileDecode filter didn't work with a non-empty EOD string
(went into an endless loop).  (Probably a new bug in 2.8.)
	- save/restore didn't properly restore the maxlength of a
dictionary, causing data to get smashed at random.  (New bug in 2.9.)
	- save didn't mark objects as old, so a nested restore had no
effect.  (New bug in 2.9.2.)
	- After returning from an OtherSubrs callback, op_type1_free
freed the saved interpreter state incorrectly.  (New bug in 2.7.)
	- Level 1 configurations didn't work because .makeoperator gave an
invalidaccess error.  (New bug in 2.9.2.)
	- ASCII85 string literals didn't work.  (Probably a new bug in 2.8.)
	- If the current global/local allocation mode was different at the
end of a file than at the beginning, an addressing fault could occur
(gs_unregister_root in gs_run_string).  (New bug in 2.9.2.)
	- After a setfileposition on a file open for reading,
fileposition would return an incorrect value, even though the stream
was actually repositioned properly.

Brings the dictionary unpacking code for the DCT filters into line with
Adobe Technical Note 5116, which describes the Picky parameter for
DCTDecode and the NoMarker, Resync, Blend, Picky, and Relax parameters for
DCTEncode.

Changes the .quit operator so that if given a negative argument, the
interpreter returns this as the error code, rather than e_Quit.

Changes the Ghostscript integer version number from 100P+10S+T to
10000P+100S+T.

Changes the default halftone screen for high-resolution devices, both
black-and-white and color.

<h2><a name="V2.9.3b_Library"></a>Library</h2>

Fixes bugs:
	- The software floating multiply code used with USE_FPU=-1 only
worked on little-endian platforms.
	- Specifying a left side bearing to .type1addpath produced an
inappropriate offset.

<h1><a name="Version2.9.2b"></a>Version 2.9.2-beta (1/2/94)</h1>

This version was distributed only to beta testers.  It adds a garbage
collector and full local and global VM support.  It is the first version
that sets languagelevel = 2, i.e., claims to be a Level 2 implementation.

<h2><a name="V2.9.2b_Documentation"></a>Documentation</h2>

Fixes bugs:
	- make.doc still referred to use_* variables in gdevx.c, and
use.doc didn't explain the use* X resources.

Notes that -Olimit=1000 is needed to compile Ghostscript on AXP systems
under OSF/1 1.3.

<h2><a name="V2.9.2b_Utilities"></a>Utilities</h2>

Fixes bugs:
	- viewgif.ps did not work with interlaced images.
	- font2c.ps omitted gsmemory.h from the #include list in compiled
fonts.

<h2><a name="V2.9.2b_Drivers"></a>Drivers</h2>

Fixes bugs:
	- The MS Windows driver hadn't been updated to work with the
new additions to the gx_device structure.
	- The BMP file driver wrote one scan line too many.
	- The cdj driver omitted an important cast to int in the error
diffusion code (FSdither macro).

Changes the SuperVGA drivers to recognize erasepage and reset the
color table, like the X driver.

Adds some fragmentary code to begin implementing the PostScript fax
extensions.

<h2><a name="V2.9.2b_Platforms"></a>Platforms</h2>

Fixes bugs:
	- The procedure initializers for the MS Windows console I/O
were missing the new reset element.
	- The makefile entry in bcwin.mak used -fdev rather than -iodev.
	- The Borland C++ makefiles exceeded MS-DOS's line length limit if
the compiler files were in the standard Borland directory (BORLANDC).
	- Some procedures weren't declared with prototypes in gp_vms.c.
	- Some declarations had to be reordered to pacify the VAX compiler.
	- Under MS Windows, Ghostscript didn't automatically de-iconify the
text window to display messages on an error exit.
	- The Unix makefile rule for gconfig_.h used echogs rather than
./echogs.
	- The Microsoft C makefile referred to an obsolete file gs.tr.
	- gp_unifs.c used strpbrk and strrchr, which some systems lack.

Updates the OS/2 code and documentation for compatibility with the current
Ghostscript version.

<h2><a name="V2.9.2b_Fonts"></a>Fonts</h2>

Fixes bugs:
	- The X11 .pfa fonts replaced their .gsf requirements in the
fontmap, but not distributed with the previous (beta) release.

Adds fontmaps appropriate for use with DEC Ultrix and OSF/1 systems.

<h2><a name="V2.9.2b_Interpreter"></a>Interpreter</h2>

Fixes bugs:
	- 4-value entries in the Metrics dictionary were interpreted with
the width and side bearing interchanged.
	- Objects large enough to require their own chunk were not freed
properly.
	- The GS_FONTPATH scanner didn't deal with the possibility that
opening a file might fail.
	- The interrupt and timeout errors incorrectly pushed an error
object on the operand stack.
	- imagemask gave an error if it was invoked with a dictionary
argument with a current color space with more than 1 parameter.
	- definefont insisted that a new font not have a FID entry.
	- Some places didn't cast char to byte when needed.
	- An extra element was left on the stack when substituting the
default font for a font whose file couldn't be found.
	- The CCITTFaxDecode filter didn't allow the dictionary to be
omitted.  (The Adobe documentation doesn't allow this, but Adobe
implementations do.)
	- When the input came from a pipe (`-') switch, opening a filter on
currentfile that required more than 1 input byte to make progress would
cause Ghostscript to hang (in sreadbuf).
	- The interpreter didn't call gs_set_lib_paths before executing a
compiled-in initialization file.
	- A stream could be closed more than once.  (New bug in 2.8.)
	- The LZW decoder produced incorrect output if a code string was
too long to fit into a single output buffer.  (New bug as of 2.8.)

Implements a special check in def to allow construction of systemdict,
which is stored in global VM but references dictionaries in local VM.

Implements additional Level 2 features:
	- %null% and %ram% IODevices.
	- startjob, exitserver.
	- Local and global VM (finish).
	- Garbage collection (for everything except names and strings).

Moves the procedures for selecting paper size from systemdict to userdict.

Sets languagelevel to 2 in Level 2 mode, since essentially all of
Level 2 is now implemented.

Factors out the Level 1 extended color facilities (CMYK color and
colorimage) as a separate configuration feature.

Adds some preliminary code to begin implementing the Adobe BCP and TBCP
communication protocols.

Changes the implementation of save and restore so that the bookkeeping
structures are allocated in the new area, not the old.  (This is an
internal change not visible at the PostScript level.)

<h2><a name="V2.9.2b_Library"></a>Library</h2>

Fixes bugs:
	- gdevprn used some preprocessor macros in formal argument
lists that ansi2knr couldn't handle.
	- pick_cell_size called gs_distance_transform with a 0 argument
that non-ANSI compilers didn't automatically promote to floating point.
	- gs_screen_init called hypot with integer arguments that
non-ANSI compilers didn't automatically promote to floating point.
	- Some places didn't cast char to byte when needed.
	- The vx/vy origin adjustment for WMode=1 wasn't implemented.
	- The pattern cache wasn't initialized properly.
	- Composite fonts didn't properly decode strings that started with
an escape sequence, which have a special (undocumented) decoding rule, and
also didn't properly decode strings with multiple consecutive escape
sequences.

Factors out the Level 1 extended color facilities (CMYK color and
colorimage) as a separate configuration feature.

<h1><a name="Version2.9.1b"></a>Version 2.9.1-beta (12/7/93)</h1>

This version was distributed only to beta testers.

<h2><a name="V2.9.1b_Utilities"></a>Utilities</h2>

Adds a viewgif.ps utility to view GIF files.  The current version does not
work with interlaced data, local color tables, or files containing more
than one image.

<h2><a name="V2.9.1b_Interpreter"></a>Interpreter</h2>

Fixes bugs:
	- putinterval and copy didn't do the right thing if the source and
destination were aliases for overlapping sections of the same array or
string.
	- The DCT filter stub didn't allow the dictionary to be omitted.
(The Adobe documentation doesn't allow this, but Adobe implementations
do.)

Adds an optional dictionary argument to the LZWDecode filter, containing
InitialCodeLength, FirstBitLowOrder, BlockData, and EarlyCh