lily/include/translator.hh

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2014 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 struct Acknowledge_information
  32 {
  33   SCM symbol_;
  34   Engraver_void_function_engraver_grob_info function_;
  35
  36   Acknowledge_information ()
  37   {
  38     symbol_ = SCM_EOL;
  39     function_ = 0;
  40   }
  41 };
  42
  43 /*
  44   Each translator class has a static list of listener records. Each
  45   record makes one explains how to register one of the class's stream event
  46   listeners to a context.
  47 */
  48 typedef struct translator_listener_record
  49 {
  50   Listener (*get_listener_) (void *, SCM event_class);
  51   SCM event_class_;
  52   struct translator_listener_record *next_;
  53
  54   translator_listener_record ()
  55   {
  56     next_ = 0;
  57     event_class_ = SCM_EOL;
  58     get_listener_ = 0;
  59   }
  60
  61 } translator_listener_record;
  62
  63 #define TRANSLATOR_DECLARATIONS_NO_LISTENER(NAME)                       \
  64 private:                                                                \
  65   public:                                                               \
  66   NAME ();                                                              \
  67   VIRTUAL_COPY_CONSTRUCTOR (Translator, NAME);                          \
  68   static SCM static_description_;                                       \
  69   static Drul_array<vector<Acknowledge_information> > acknowledge_static_array_drul_; \
  70   virtual void fetch_precomputable_methods (Translator_void_method_ptr methods[]); \
  71   virtual SCM static_translator_description () const;                   \
  72   virtual SCM translator_description () const;                          \
  73   static Engraver_void_function_engraver_grob_info static_get_acknowledger (SCM sym); \
  74   static Engraver_void_function_engraver_grob_info static_get_end_acknowledger(SCM); \
  75   virtual Engraver_void_function_engraver_grob_info get_acknowledger (SCM sym) \
  76   {                                                                     \
  77     return static_get_acknowledger (sym);                               \
  78   }                                                                     \
  79   virtual Engraver_void_function_engraver_grob_info get_end_acknowledger (SCM sym) \
  80   {                                                                     \
  81     return static_get_end_acknowledger (sym);                           \
  82   } \
  83   /* end #define */
  84
  85 #define TRANSLATOR_DECLARATIONS(NAME)                                   \
  86   TRANSLATOR_DECLARATIONS_NO_LISTENER(NAME)                             \
  87 private:                                                                \
  88   static translator_listener_record *listener_list_;                    \
  89 public:                                                                 \
  90   virtual translator_listener_record *get_listener_list () const        \
  91   {                                                                     \
  92     return listener_list_;                                              \
  93   }                                                                     \
  94   /* end #define */
  95
  96 #define DECLARE_TRANSLATOR_LISTENER(m)                  \
  97 public:                                                 \
  98 inline void listen_ ## m (Stream_event *);              \
  99 /* Should be private */                                 \
 100 static void _internal_declare_ ## m ();                 \
 101 private:                                                \
 102  static Listener _get_ ## m ## _listener (void *, SCM); \
 103 DECLARE_LISTENER (_listen_scm_ ## m);
 104
 105 #define DECLARE_ACKNOWLEDGER(x) public : void acknowledge_ ## x (Grob_info); protected:
 106 #define DECLARE_END_ACKNOWLEDGER(x) public : void acknowledge_end_ ## x (Grob_info); protected:
 107
 108 enum Translator_precompute_index
 109 {
 110   START_TRANSLATION_TIMESTEP,
 111   STOP_TRANSLATION_TIMESTEP,
 112   PROCESS_MUSIC,
 113   PROCESS_ACKNOWLEDGED,
 114   TRANSLATOR_METHOD_PRECOMPUTE_COUNT,
 115 };
 116
 117 /*
 118   Translate music into grobs.
 119 */
 120 class Translator
 121 {
 122   void init ();
 123
 124 public:
 125   Context *context () const { return daddy_context_; }
 126
 127   Translator (Translator const &);
 128
 129   SCM internal_get_property (SCM symbol) const;
 130
 131   virtual Output_def *get_output_def () const;
 132   virtual Translator_group *get_daddy_translator ()const;
 133   virtual Moment now_mom () const;
 134   virtual bool must_be_last () const;
 135
 136   virtual void initialize ();
 137   virtual void finalize ();
 138
 139   virtual void connect_to_context (Context *c);
 140   virtual void disconnect_from_context (Context *c);
 141
 142   void stop_translation_timestep ();
 143   void start_translation_timestep ();
 144   void process_music ();
 145   void process_acknowledged ();
 146
 147   Context *get_score_context () const;
 148   Global_context *get_global_context () const;
 149
 150   TRANSLATOR_DECLARATIONS (Translator);
 151   DECLARE_SMOBS (Translator);
 152
 153 protected:                      // should be private.
 154   Context *daddy_context_;
 155   void protect_event (SCM ev);
 156   virtual void derived_mark () const;
 157   static void add_translator_listener (translator_listener_record **listener_list,
 158                                        translator_listener_record *r,
 159                                        Listener (*get_listener) (void *, SCM),
 160                                        const char *ev_class);
 161   SCM static_translator_description (const char *grobs,
 162                                      const char *desc,
 163                                      translator_listener_record *listener_list,
 164                                      const char *read,
 165                                      const char *write) const;
 166
 167   friend class Translator_group;
 168 };
 169
 170 void add_translator (Translator *trans);
 171
 172 Translator *get_translator (SCM s);
 173 Moment get_event_length (Stream_event *s, Moment now);
 174 Moment get_event_length (Stream_event *s);
 175 DECLARE_UNSMOB (Translator, translator);
 176
 177 /*
 178   This helper is only meaningful inside listen_* methods.
 179 */
 180 extern bool internal_event_assignment (Stream_event **old_ev, Stream_event *new_ev, const char *function);
 181 #define ASSIGN_EVENT_ONCE(o,n) internal_event_assignment (&o, n, __FUNCTION__)
 182
 183 #endif // TRANSLATOR_HH