Support TeX elements in FreeType renderer. * libinterp/corefcn/txt-eng.cc: New file. Contains mapping from symbol name to character code, in Unicode and MS symbol. * libinterp/corefcn/modules.mk (COREFCN_SRC): Add txt-eng.cc. * libinterp/corefcn/oct-tex-lexer.ll: Add "\n" to rules applicable to ".", as the latter does not include new line characters. * libinterp/corefcn/oct-tex-parser.yy: Remove debug statements. * libinterp/corefcn/txt-eng.ft.cc (gripe_missing_glyph, gripe_glyph_render): Change signature from char to FT_ULong. (ft_render::ft_render): Adapt to new/removed members. (ft_render::~ft_render): Remove use of fonts member. (ft_render::set_font): Likewise. Use font instead. (ft_render::push_new_line): Likewise. Change meaning of yoffset and initialize line_yoffset. (ft_render::update_line_bbox): New method. (ft_render::set_mode): Change meaning of yoffset and initialize line_yoffset. (ft_render::process_character): New method. (ft_render::visit(text_element_string)): Use it. (ft_render::visit(text_element_list), ft_render::visit(text_element_subscript), ft_render::visit(text_element_superscript), ft_render::visit(text_element_color), ft_render::visit(text_element_fontsize), ft_render::visit(text_element_fontname), ft_render::visit(text_element_fontstyle), ft_render::visit(text_element_symbol)): New methods. (ft_render::set_color): Use color member instead of red/green/blue. * libinterp/corefcn/txt-eng-ft.h (ft_render::visit(text_element_list), ft_render::visit(text_element_subscript), ft_render::visit(text_element_superscript), ft_render::visit(text_element_color), ft_render::visit(text_element_fontsize), ft_render::visit(text_element_fontname), ft_render::visit(text_element_fontstyle), ft_render::visit(text_element_symbol)): New methods. (ft_render::update_line_bbox, ft_render::process_character): New methods. (ft_render::current_face): Removed method.i (ft_render::font): New member, replaces obsolete ft_render::fonts. (ft_render::line_yoffset): New member. (ft_render::color): New member, replaces obsolete red, green and blue. (ft_render::ft_font::ft_font()): Implement default constructor. (ft_render::ft_font::operator=): Fix incorrect use of FT_Reference_Face return value. (ft_render::ft_font::is_valid): New method. * libinterp/corefcn/txt-eng.h (class text_element_symbol, class text_element_fontname, class text_element_fontsize, class text_element_fontname, class text_element_fontstyle, class text_element_color): Add forward definition. (text_element_symbol::invalid_code): New enum. (text_element_symbol::code): New member. (text_element_symbol::text_element_symbol): Initialize it. (text_element_symbol::get_symbol_code): New method. (text_element_fontstyle::get_fontstyle): New method. (text_element_fontname::get_fontname): Renamed from fontname. (text_element_fontsize::get_fontsize): Renamed from fontsize.

## Disable the next line if you really need to see the
## thread create/exit messages.

set print thread-events off

## Helpful macros for debugging Octave.

############################################################
## Display a dim-vector object.

define display-dims
  echo ndims: \ 
  output $arg0.rep[-1]
  echo \ndims: \ 
  output *$arg0.rep@$arg0.rep[-1]
  echo \n
  dont-repeat
end

document display-dims
Usage: display-dims DIM_VECTOR
Display the contents of an Octave dimension vector.
end

############################################################
## Display a dense array object.

define display-dense-array
  echo array object: \ 
  output $arg0
  echo \ndimensions:\n
  display-dims $arg0.dimensions
  echo \nrep = \ 
  output *$arg0.rep
  echo \nrep.data = \ 
  output *$arg0.rep.data@$arg0.rep.len
  echo \n
  dont-repeat
end

document display-dense-array
Usage: display-dense-array ARRAY
Display the contents of an ordinary, i.e., dense Octave array.

See also [display-sparse-array] for showing the contents
of sparse Octave arrays.
end

############################################################
## Display a sparse array object.

define display-sparse-array
  echo sparse object: \ 
  output $arg0
  echo \ndimensions.rep[0] = \ 
  display-dims $arg0.dimensions
  echo \ndimensions.rep[1] = \ 
  output $arg0.dimensions.rep[1]
  echo \nrep = \ 
  output *$arg0.rep
  echo \nrep.d = \ 
  output *$arg0.rep.d@$arg0.rep.nzmx
  echo \nrep.r = \ 
  output *$arg0.rep.r@$arg0.rep.nzmx
  echo \nrep.c = \ 
  output *$arg0.rep.c@($arg0.rep.ncols+1)
  echo \n
  dont-repeat
end

document display-sparse-array
Usage: display-sparse-array SPARSE_ARRAY
Display the contents of a sparse Octave array.

See also [display-dense-array] for showing the contents
of ordinary Octave arrays.
end

############################################################

## Display Octave debugging stack 

define show-octave-dbstack
  call show_octave_dbstack ()
end

document show-octave-dbstack
Usage: show-octave-dbstack
Display the contents of the current Octave debugging stack.

This is the function stack that the Octave interpreter is processing
and will be different from the C++ stack being debugged with gdb.
end