cl-pslib

2024-10-12

A CFFI wrapper for the pslib library, a library for generating PostScript files.

Upstream URL

codeberg.org/cage/cl-pslib

Author

cage <cage-dev@twistfold.it>

Maintainer

cage

License

LLGPL
README

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 a cl-color object as parameter;
  • there is no '(ps_)boot' method; when an instance of psdoc is created theinitialize-instance of that class will call ps_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 in cl-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 of text-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 and and-templatea 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 (use set-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.

Dependencies (4)

  • alexandria
  • cffi
  • cl-colors2
  • cl-ppcre

Dependents (1)

  • GitHub
  • Quicklisp