Daniel@0: /* Part of DML (Digital Music Laboratory)
Daniel@0: 	Copyright 2014-2015 Samer Abdallah, University of London
Daniel@0: 	 
Daniel@0: 	This program is free software; you can redistribute it and/or
Daniel@0: 	modify it under the terms of the GNU General Public License
Daniel@0: 	as published by the Free Software Foundation; either version 2
Daniel@0: 	of the License, or (at your option) any later version.
Daniel@0: 
Daniel@0: 	This program is distributed in the hope that it will be useful,
Daniel@0: 	but WITHOUT ANY WARRANTY; without even the implied warranty of
Daniel@0: 	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Daniel@0: 	GNU General Public License for more details.
Daniel@0: 
Daniel@0: 	You should have received a copy of the GNU General Public
Daniel@0: 	License along with this library; if not, write to the Free Software
Daniel@0: 	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Daniel@0: */
Daniel@0: 
Daniel@0: :- module(api_r_plot, []).
Daniel@0: 
Daniel@0: :- use_module(library(http/http_dispatch)).
Daniel@0: :- use_module(library(http/http_parameters)).
Daniel@0: :- use_module(library(sandbox)).
Daniel@0: :- use_module(library(insist)).
Daniel@0: :- use_module(library(fileutils)).
Daniel@0: :- use_module(library(swipe)).
Daniel@0: :- use_module(library(httpfiles)).
Daniel@0: :- use_module(library(real)).
Daniel@0: 
Daniel@0: :- set_prolog_flag(double_quotes,string).
Daniel@0: :- set_prolog_flag(back_quotes,symbol_char).
Daniel@0: 
Daniel@0: :- http_handler(api(r/render), r_figure_render, []).
Daniel@0: 
Daniel@0: :- setting(r_plot:pixels_per_inch,number,150,"Pixels per inch for in browser figures").
Daniel@0: :- setting(r_plot:default_figure_format,oneof([png,svg]),svg,"Default R figure rendering method").
Daniel@0: 
Daniel@0: %% figure_render(+Request) is det.
Daniel@0: %
Daniel@0: %  HTTP handler for rendering R figures.
Daniel@0: r_figure_render(Request) :-
Daniel@0:    setting(r_plot:pixels_per_inch,DefPPI),
Daniel@0:    http_parameters(Request,
Daniel@0:       [ code(CodeA,[ atom, optional(false), description("Prolog rendering goal")])
Daniel@0:       , format(F, [ oneof([eps,svg,pdf,png]), optional(false), description("Output format") ]) 
Daniel@0:       , width(W,  [ number, optional(true), default(10), description("Width in cm")])
Daniel@0:       , height(H, [ number, optional(true), default(6), description("Height in cm")])
Daniel@0:       , font_name(FN,  [ atom, optional(true), default(helvetica) ])
Daniel@0:       , font_size(FS,  [ number, optional(true), default(10) ])
Daniel@0:       , ppi(PPI,       [ number, optional(true), default(DefPPI), description("PNG resolution")])
Daniel@0:       ]),
Daniel@0:    debug(r_plot,"Attempting to parse \"~s\".",[CodeA]),
Daniel@0:    read_term_from_atom(CodeA,Code,[]),
Daniel@0:    (  user_db:logged_on(A)
Daniel@0:    -> debug(r_plot,"Logged on as ~w, no checking",[A])
Daniel@0:    ;  debug(r_plot,"Checking ~q for safety...",[Code]),
Daniel@0:       sandbox:safe_goal(Code),
Daniel@0:       debug(r_plot,"Goal is safe.",[])
Daniel@0:    ),
Daniel@0:    insist(with_temp_dir(Dir, (
Daniel@0:       render(F,Code,Dir,File, [size(W,H), ppi(PPI), font_name(FN), font_size(FS) ]),
Daniel@0:       debug(r_plot,'Replying with file ~s',[File]),
Daniel@0:       reply_file(File,F)
Daniel@0:    ))).
Daniel@0: 
Daniel@0: 
Daniel@0: render(png,Code,D,PNGPath,Opts) :- !,
Daniel@0:    file_name_extension(tmp,png,PNGFile),
Daniel@0:    directory_file_path(D,PNGFile,PNGPath),
Daniel@0:    render(pdf,Code,D,EPSFile,Opts),
Daniel@0:    option(ppi(PPI),Opts,300),
Daniel@0:    run(sh(0>>0, "gs -dBATCH -dNumRenderingThreads=2 -dEPSCrop -dNOPAUSE -sDEVICE=pngalpha -sOutputFile=~s -r~d -q ~s",
Daniel@0:                      [PNGPath+write,\PPI,EPSFile+read])).
Daniel@0: 
Daniel@0: % render(png,Code,D,Opts) :- !, option(ppi(PPI),Opts,300), render(png(PPI),Code,D,Opts).
Daniel@0: render(Fmt,Code,Dir,Path,Opts) :- 
Daniel@0:    file_name_extension(tmp,Fmt,File),
Daniel@0:    directory_file_path(Dir,File,Path),
Daniel@0:    debug(r_plot,'Running ~q',[print_fig(Fmt,Code,Path,Opts)]),
Daniel@0:    with_mutex(r_plot,api_r_plot:print_fig(Fmt,Code,Path,Opts)).
Daniel@0: 
Daniel@0: print_fig(Fmt,Code,Path,Opts) :-
Daniel@0:    debug(r_plot,'In print_fig...',[]),
Daniel@0:    option(size(Width,Height),Opts),
Daniel@0:    maplist(cm_inch,[Width,Height],[WidthInches,HeightInches]),
Daniel@0:    debug(r_plot,'Getting device ~w: ~s',[Fmt,Path]),
Daniel@0:    dev(Fmt,Path,WidthInches,HeightInches,Dev),
Daniel@0:    debug(r_plot,'Got device ~q',[Dev]),
Daniel@0:    setup_call_cleanup( 
Daniel@0:       r(Dev), 
Daniel@0:       call_cleanup( 
Daniel@0:          with_output_to(string(_),Code), 
Daniel@0:         exception(Ex), 
Daniel@0:         debug(r_plot,'Exception running R code: ~q',[Ex])),
Daniel@0:       r('dev.off()')).
Daniel@0: 
Daniel@0: dev(pdf,Name,W,H,pdf(+Name,width=W,height=H)).
Daniel@0: dev(eps,Name,W,H,cairo_ps(+Name,width=W,height=H)).
Daniel@0: dev(svg,Name,W,H,svg(+Name,width=W,height=H)).
Daniel@0: dev(png(PPI),Name,W,H,png(+Name,width=WP,height=HP)) :- WP is PPI*W, HP is PPI*H.
Daniel@0: 
Daniel@0: cm_inch(CM,INCH) :- INCH is CM/2.54.
Daniel@0: