source/sequencer.h

   1 #ifndef MSP_DEMOSCENE_SEQUENCER_H_
   2 #define MSP_DEMOSCENE_SEQUENCER_H_
   3
   4 #include <vector>
   5 #include <sigc++/signal.h>
   6 #include <msp/time/timedelta.h>
   7 #include <msp/time/timestamp.h>
   8
   9 class Sequencer
  10 {
  11 public:
  12         class Action
  13         {
  14         protected:
  15                 Action() { }
  16         public:
  17                 virtual ~Action() { }
  18
  19                 virtual void start(float, float) { }
  20                 virtual void beat(int) { }
  21                 virtual void tick(float, float) { }
  22                 virtual void end(float) { }
  23         };
  24
  25         class InterpolationAction: public Action
  26         {
  27         protected:
  28                 bool hermite;
  29                 float start_beat;
  30                 float duration;
  31
  32                 InterpolationAction(bool = false);
  33
  34         public:
  35                 virtual void start(float, float);
  36                 virtual void tick(float, float);
  37                 virtual void end(float);
  38                 virtual void interpolate(float, float) { }
  39         };
  40
  41 private:
  42         struct Segment
  43         {
  44                 Action *action;
  45                 float start_beat;
  46                 float end_beat;
  47         };
  48
  49 public:
  50         sigc::signal<void> signal_finished;
  51
  52 private:
  53         Msp::Time::TimeDelta secs_per_beat;
  54         std::vector<Action *> static_actions;
  55         std::vector<Segment> segments;
  56         std::vector<Segment>::const_iterator begin;
  57         std::vector<Segment>::const_iterator end;
  58         bool started;
  59         float beat;
  60         float next_event;
  61
  62 public:
  63         Sequencer(float = 120.0f);
  64
  65         void set_beats_per_minute(float);
  66         float get_beats_per_minute() const { return Msp::Time::min/secs_per_beat; }
  67         void add_static_action(Action &);
  68         void add_action(Action &, float, float);
  69
  70         void start();
  71         void seek(float);
  72         void tick(const Msp::Time::TimeDelta &);
  73 private:
  74         void advance_to(float);
  75         void update_next_event();
  76 public:
  77         float get_current_beat() const { return beat; }
  78 };
  79
  80 #endif