lily/include/translator.hh

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #ifndef TRANSLATOR_HH
  21 #define TRANSLATOR_HH
  22
  23 #include "global-ctor.hh"
  24 #include "lily-proto.hh"
  25 #include "virtual-methods.hh"
  26 #include "input.hh"             // for error reporting
  27 #include "smobs.hh"
  28 #include "std-vector.hh"
  29 #include "protected-scm.hh"
  30
  31 #define TRANSLATOR_DECLARATIONS_NO_LISTENER(NAME)                       \
  32   public:                                                               \
  33   NAME ();                                                              \
  34   VIRTUAL_COPY_CONSTRUCTOR (Translator, NAME);                          \
  35   static SCM static_description_;                                       \
  36   static Drul_array<vector<Acknowledge_information> > acknowledge_static_array_drul_; \
  37   virtual void fetch_precomputable_methods (Callback methods[]); \
  38   virtual SCM static_translator_description () const;                   \
  39   virtual SCM translator_description () const;                          \
  40   static Grob_info_callback static_get_acknowledger (SCM sym);          \
  41   static Grob_info_callback static_get_end_acknowledger(SCM);           \
  42   virtual Grob_info_callback get_acknowledger (SCM sym)                 \
  43   {                                                                     \
  44     return static_get_acknowledger (sym);                               \
  45   }                                                                     \
  46   virtual Grob_info_callback get_end_acknowledger (SCM sym)             \
  47   {                                                                     \
  48     return static_get_end_acknowledger (sym);                           \
  49   } \
  50   /* end #define */
  51
  52 /*
  53   Each translator class has a static alist of event class symbols
  54   mapping to callbacks that are called with a translator instance and
  55   a stream event when an event of the appropriate event class is
  56   announced in a context.
  57 */
  58
  59 #define TRANSLATOR_DECLARATIONS(NAME)                                   \
  60   TRANSLATOR_DECLARATIONS_NO_LISTENER(NAME)                             \
  61 private:                                                                \
  62   static Protected_scm listener_list_;                                  \
  63 public:                                                                 \
  64   virtual SCM get_listener_list () const                                \
  65   {                                                                     \
  66     return listener_list_;                                              \
  67   }                                                                     \
  68   /* end #define */
  69
  70 #define DECLARE_TRANSLATOR_LISTENER(m)                  \
  71 public:                                                 \
  72 inline void listen_ ## m (Stream_event *);              \
  73 /* Should be private */                                 \
  74 static void _internal_declare_ ## m ();
  75
  76 #define DECLARE_ACKNOWLEDGER(x) public : void acknowledge_ ## x (Grob_info); protected:
  77 #define DECLARE_END_ACKNOWLEDGER(x) public : void acknowledge_end_ ## x (Grob_info); protected:
  78
  79 enum Translator_precompute_index
  80 {
  81   START_TRANSLATION_TIMESTEP,
  82   STOP_TRANSLATION_TIMESTEP,
  83   PROCESS_MUSIC,
  84   PROCESS_ACKNOWLEDGED,
  85   TRANSLATOR_METHOD_PRECOMPUTE_COUNT,
  86 };
  87
  88 /*
  89   Translate music into grobs.
  90 */
  91 class Translator : public Smob<Translator>
  92 {
  93 public:
  94   // We don't make Grob_info_callback specific to Engraver since we
  95   // otherwise get into a circular mess with regard to the definitions
  96   // as the timing of Engraver is exercised from within Translator
  97   typedef void (Translator::*Grob_info_callback) (Grob_info);
  98   typedef void (Translator::*Callback) (void);
  99   int print_smob (SCM, scm_print_state *);
 100   SCM mark_smob () const;
 101   static const char type_p_name_[];
 102   virtual ~Translator ();
 103 private:
 104   void init ();
 105
 106 public:
 107   Context *context () const { return daddy_context_; }
 108
 109   Translator (Translator const &);
 110
 111   SCM internal_get_property (SCM symbol) const;
 112
 113   virtual Output_def *get_output_def () const;
 114   virtual Translator_group *get_daddy_translator ()const;
 115   virtual Moment now_mom () const;
 116   virtual bool must_be_last () const;
 117
 118   virtual void initialize ();
 119   virtual void finalize ();
 120
 121   virtual void connect_to_context (Context *c);
 122   virtual void disconnect_from_context (Context *c);
 123
 124   void stop_translation_timestep ();
 125   void start_translation_timestep ();
 126   void process_music ();
 127   void process_acknowledged ();
 128
 129   Context *get_score_context () const;
 130   Global_context *get_global_context () const;
 131
 132   TRANSLATOR_DECLARATIONS (Translator);
 133
 134 protected:                      // should be private.
 135   Context *daddy_context_;
 136   void protect_event (SCM ev);
 137   friend class Callback_wrapper;
 138   virtual void derived_mark () const;
 139   static SCM event_class_symbol (const char *ev_class);
 140   SCM static_translator_description (const char *grobs,
 141                                      const char *desc,
 142                                      SCM listener_list,
 143                                      const char *read,
 144                                      const char *write) const;
 145
 146   friend class Translator_group;
 147 };
 148
 149 struct Acknowledge_information
 150 {
 151   SCM symbol_;
 152   Translator::Grob_info_callback function_;
 153
 154   Acknowledge_information ()
 155   {
 156     symbol_ = SCM_EOL;
 157     function_ = 0;
 158   }
 159 };
 160
 161
 162 void add_translator (Translator *trans);
 163
 164 Translator *get_translator (SCM s);
 165 Moment get_event_length (Stream_event *s, Moment now);
 166 Moment get_event_length (Stream_event *s);
 167
 168 /*
 169   This helper is only meaningful inside listen_* methods.
 170 */
 171 extern bool internal_event_assignment (Stream_event **old_ev, Stream_event *new_ev, const char *function);
 172 #define ASSIGN_EVENT_ONCE(o,n) internal_event_assignment (&o, n, __FUNCTION__)
 173
 174 #endif // TRANSLATOR_HH