cl-pslib
2024-10-12
A CFFI wrapper for the pslib library, a library for generating PostScript files.
1Important note
The 'ps' nickname for this package has been removed.This means that if you are using this library you should replace all occurences of the 'ps' package qualifier with 'cl-pslib'.
Examples
from:
(ps:get-value doc "boxheight")
to:
(cl-pslib:get-value doc "boxheight")
and from:
(defpackage :foo
(:use :ps))
to:
(defpackage :foo
(:use :cl-pslib))
Alternatively., if you are using ECL, ABCL, CCL or SBCL compiler you can setup a package local nickname as showed here.
2Introduction
Cl-pslib is a (thin) wrapper around pslib a library for generating PostScript files.
3The wrapper
Cl-pslib use CFFI and SWIG to interface with foreign (non lisp)library and generate the low-level lisp wrapper respectively.cl-pslib does not export the raw (CFFI) pslib API but use CLOS instead.
A psdoc C struct pointer is wrapped in the class psdoc, most of the functions to manipulate this pointer are wrapped in lisp methods specialized for that class.
3.1Parameters
Pslib use a lot of parameters to configure its behavior.
Example:
(get-value doc "boxheight")
I found this very unpractical so i tried to generate lisp constants to match the corresponding string parameter
(get-value doc +value-key-boxheight+)
3.2Function name
As general rule the methods for the class psdoc are the same of theones of the pslib with the character "_" substituted by "-".There are some exceptions listed below.
native name | lisp name |
---|---|
PS_set_border_color |
set-border-link-color |
PS_set_border_dash |
set-border-link-dash |
PS_set_border_style |
set-border-link-style |
PS_open, PS_open_mem |
open-doc |
PS_fill |
fill-path |
PS_show and PS_show2 |
show |
PS_show_xy and PS_show_xy2 |
show-xy |
PS_string_geometry , PS_stringwidth and PS_stringwidth2 |
string-geometry |
PS_symbol |
font-symbol |
PS_symbol_name |
font-symbol-name |
PS_symbol_width |
font-symbol-width |
3.3Other differences
setcolor
can accept acl-color
object as parameter;- there is no '(ps_)boot' method; when an instance of
psdoc
is created theinitialize-instance
of that class will callps_boot
if needed.The same is true for '(ps_)new' method; open-doc
method will pass the output of pslib (i.e.the PostScriptfile) to a lisp callback function if the second argument of the function isnil; by default the callback just copy the output incl-pslib:*callback-string*
.This maybe can be useful for generate a file in a web application.There is another callback:
write-to-stream
that write the postscript code to a stream (by default the stream is bound to*standard-output*
)(let* ((cl-pslib:*callback-stream* *standard-output*) (doc (make-instance 'cl-pslib:psdoc :writeproc (cffi:callback write-to-stream)))) ;; rest of the code here )
- the
string-geometry
method return an instance oftext-metrics
class
4Issues
Note that the whole library is in an alpha stage, testing is still in progress, please see section below
- to use the template features
begin-template
andand-template
a version >= 0.47 must be used.
4.1Missing function
The high-level API does not still remap this functions:PS_free_glyph_list
;PS_get_buffer
;PS_glyph_list
;PS_new2
;PS_open_fp
;PS_hyphenate
;PS_list_parameters
;PS_list_resources
;PS_list_values
;PS_set_gstate
;PS_setdash
(useset-polydash
instead).
5BUGS
Please file bug report on the issue tracker
6License
This library is released under Lisp Lesser General Public license (seeCOPYING.LESSER file)Examples are released under GPL version 3 or later
7NO WARRANTY
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.