view libinterp/corefcn/text-renderer.cc @ 29470:2ae4764180c6

Initial implementation of a LaTeX interpreter (bug #59546). * NEWS: Announce basic support for "latex" interpreter. * plot.txi: Restructure the "Use of the interpreter Property" section to include 3 subsections, one for each interpreter type. In "Printing and Saving Plots" describe the new behavior. * print.m: Document new behavior. * contributors.in: Add Andrej Lojdl, a former GSoC student that worked on this subject. Even though there is not much left of his original work, it served as a very useful starting point. * base-text-renderer.h, base-text-renderer.cc: New enum to store symbolic constants for rotation angles. (base_text_renderer::rotate_pixels): New utility method. Code extracted from ft_text_renderer::render. (base_text_renderer::rotation_to_mode): Moved from ft_text_renderer class. (base_text_renderer::fix_bbox_anchor): New utility method. Code extracted from ft_text_renderer::text_to_pixels. * ft_text_renderer.cc (ft_text_renderer::render, ft_text_renderer::text_to_pixels): Make use of base class utility functions. * gl2ps-print.cc: New counter variable m_svg_def_index for safe inclusion of defs coming from dvisvgm. (gl2ps_renderer::format_svg_element): New function to manipulate svg elements obtained from dvisvgm so as to position them properly on the figure and change their color. (gl2ps_renderer::strlist_to_svg): If the str_list object returned from text_to_strlist contains an svg element, use format_svg_element to handle position and color and then return it. Otherwise, use <g> and <text> elements rather than <text> and <tspan> elements which are not supported by Qt's svg renderer (svg-tiny implementation). (gl2ps_renderer::strlist_to_ps): If the str_list object returned from text_to_strlist contains an svg element, raise a warning about the necessity of using -svgconvert. * latex-text-renderer.h, latex-text-renderer.cc: New files to hold the latex_interpreter class. * libinterp/corefcn/module.mk: Add new files to the build system. * text-renderer.h, text-renderer.cc (text_renderer): New data member latex_rep to hold a pointer to an instance of a latex_renderer. (text_renderer::~text_renderer, get_extent, set_anti_aliasing, set_font, set_color, text_to_pixels, text_to_strlist): Duplicate action of the latex_rep. (text_renderer::latex_ok): New method to test the usability of the latex_renderer. (text_renderer::string::svg_element, text_renderer::string::set_svg_element, text_renderer::string::get_svg_element): New string data member to hold preformated svg element. Provide accessor methods. * acinclude.m4: Add QtSvg to the list of imported QT_MODULES. * octave-svgconvert.cc: Overhaul program to make use of Qt's QSvgRenderer when rendering to PDF.
author Pantxo Diribarne <pantxo.diribarne@gmail.com>
date Mon, 22 Mar 2021 21:32:54 +0100
parents 0a5b15007766
children af41ebf3d1b3
line wrap: on
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////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2009-2021 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include "base-text-renderer.h"
#include "error.h"
#include "errwarn.h"
#include "ft-text-renderer.h"
#include "latex-text-renderer.h"
#include "oct-env.h"
#include "text-renderer.h"

namespace octave
{
  text_renderer::text_renderer (void)
    : rep (make_ft_text_renderer ()), latex_rep (make_latex_text_renderer ())
  { }

  text_renderer::~text_renderer (void)
  {
    delete rep;
    delete latex_rep;
  }

  bool
  text_renderer::ok (void) const
  {
    static bool warned = false;

    if (! rep)
      {
        if (! warned)
          {
            warn_disabled_feature ("opengl_renderer::render_text",
                                   "rendering text (FreeType)");

            warned = true;
          }
      }

    return rep != nullptr;
  }

  bool
  text_renderer::latex_ok (void) const
  {
    static bool warned = false;

    if (! sys::env::getenv ("OCTAVE_LATEX_DEBUG_FLAG").empty ()
        && ! latex_rep && ! warned)
      {
        warning_with_id ("Octave:LaTeX:internal-error",
                         "latex_renderer: unusable latex tool-chain");
        warned = true;
      }

    return latex_rep != nullptr;
  }

  Matrix
  text_renderer::get_extent (text_element *elt, double rotation)
  {
    static Matrix empty_extent (1, 4, 0.0);

    return ok () ? rep->get_extent (elt, rotation) : empty_extent;
  }

  Matrix
  text_renderer::get_extent (const std::string& txt, double rotation,
                             const caseless_str& interpreter)
  {
    static Matrix retval (1, 4, 0.0);

    if (interpreter == "latex" && latex_ok ())
      retval = latex_rep->get_extent (txt, rotation, interpreter);
    else if (ok ())
      retval = rep->get_extent (txt, rotation, interpreter);

    return retval;
  }

  void
  text_renderer::set_anti_aliasing (bool val)
  {
    if (ok ())
      rep->set_anti_aliasing (val);

    if (latex_ok ())
      latex_rep->set_anti_aliasing (val);
  }

  octave_map
  text_renderer::get_system_fonts (void)
  {
    octave_map retval;

    if (ok ())
      retval = rep->get_system_fonts ();

    return retval;
  }

  void
  text_renderer::set_font (const std::string& name, const std::string& weight,
                           const std::string& angle, double size)
  {
    if (ok ())
      rep->set_font (name, weight, angle, size);

    if (latex_ok ())
      latex_rep->set_font (name, weight, angle, size);
  }

  void
  text_renderer::set_color (const Matrix& c)
  {
    if (ok ())
      rep->set_color (c);

    if (latex_ok ())
      latex_rep->set_color (c);
  }

  void
  text_renderer::text_to_pixels (const std::string& txt,
                                 uint8NDArray& pxls, Matrix& bbox,
                                 int halign, int valign, double rotation,
                                 const caseless_str& interpreter,
                                 bool handle_rotation)
  {
    static Matrix empty_bbox (1, 4, 0.0);
    static uint8NDArray empty_pxls;

    if (interpreter == "latex" && latex_ok ())
      latex_rep->text_to_pixels (txt, pxls, bbox, halign, valign, rotation,
                                 interpreter, handle_rotation);
    else if (ok ())
      rep->text_to_pixels (txt, pxls, bbox, halign, valign, rotation,
                           interpreter, handle_rotation);
    else
      {
        bbox = empty_bbox;
        pxls = empty_pxls;
      }
  }

  void
  text_renderer::text_to_strlist (const std::string& txt,
                                  std::list<text_renderer::string>& lst,
                                  Matrix& bbox, int halign, int valign,
                                  double rotation,
                                  const caseless_str& interpreter)
  {
    static Matrix empty_bbox (1, 4, 0.0);
    static std::list<text_renderer::string> empty_lst;

    if (interpreter == "latex" && latex_ok ())
      latex_rep->text_to_strlist (txt, lst, bbox, halign, valign, rotation,
                                  interpreter);
    else if (ok ())
      rep->text_to_strlist (txt, lst, bbox, halign, valign, rotation,
                            interpreter);
    else
      {
        bbox = empty_bbox;
        lst = empty_lst;
      }
  }
}