command.hh

   1 #ifndef COMMAND_HH
   2 #define COMMAND_HH
   3 #include "glob.hh"
   4
   5 #include "vray.hh"
   6 #include "string.hh"
   7
   8 enum Commandcode {
   9         NOP,
  10         INTERPRET,
  11         TYPESET,
  12         BREAK_PRE,BREAK_MIDDLE, BREAK_POST, BREAK_END
  13 };
  14 /// set a nonrythmical symbol
  15 struct Command {
  16     Commandcode code;
  17
  18     Real when;
  19     /// analogous to argv[]
  20     svec<String> args;
  21     int priority;
  22
  23     /****************/
  24
  25     Command();
  26     Command(Real w);
  27     bool isbreak()const;
  28     void print() const;
  29 };
  30
  31 /**
  32     A nonrhythmical "thing" in a  staff is called a "command".
  33     Commands have these properties:
  34
  35     \begin{itemize}
  36     \item They are \bf{not} rhythmical, i.e. they do not have  a duration
  37     \item They have a staff-wide impact, i.e. a command cannot be targeted at
  38     only one voice in the staff: two voices sharing a staff can't have
  39     different clefs
  40     \item Commands are ordered, that is, when from musical point of view the
  41     commands happen simultaneously, the order in which Staff receives the
  42     commands can still make a difference in the output
  43     \item Some commands are actually score wide, so Score has to issue these
  44     commands to the Staff, eg. BREAK commands
  45     \end{itemize}
  46
  47     At this moment we have three classes of commands:
  48     \begin{description}
  49     INTERPRET commands are not grouped.
  50     \item[TYPESET] These commands instruct the Staff to
  51     typeset symbols on the output, eg meter/clef/key changes
  52     \item[INTERPRET] These commands do not produce output, instead,
  53     they change the interpretation of other commands or requests.
  54     example: shift output vertically, set the key.
  55     \item[BREAK_XXX] These commands group TYPESET commands in
  56     prebreak and postbreak commands. \See{Col}.
  57     Staff can insert additional commands in a sequence of BREAK_XXX
  58     commands, eg. key change commands
  59
  60     \end{description}
  61
  62     These commands are generated by Score, since they have to be the
  63     same for the whole score.
  64
  65
  66     \begin{description}
  67     \item[BREAK_PRE]
  68     \item[BREAK_MIDDLE]
  69     \item[BREAK_POST]
  70     \item[BREAK_END]
  71     \item[TYPESET] METER,BAR
  72     \end{description}
  73
  74
  75     Commands can be freely copied, they do not have virtual methods.
  76     */
  77
  78
  79 #endif