source/libr2c2/speedquantizer.cpp

   1 #include "speedquantizer.h"
   2
   3 using namespace std;
   4 using namespace Msp;
   5
   6 namespace R2C2 {
   7
   8 SpeedQuantizer::SpeedQuantizer(unsigned n):
   9         steps(n+1),
  10         weight_limit(10)
  11 {
  12         if(n<1)
  13                 throw InvalidParameterValue("Must have at leats one speed step");
  14 }
  15
  16 void SpeedQuantizer::learn(unsigned i, float s, float w)
  17 {
  18         if(i>=steps.size())
  19                 throw InvalidParameterValue("Speed step index out of range");
  20         steps[i].add(s, w);
  21 }
  22
  23 float SpeedQuantizer::get_speed(unsigned i) const
  24 {
  25         if(i==0)
  26                 return 0;
  27         if(steps[i].weight>=weight_limit)
  28                 return steps[i].speed;
  29
  30         unsigned low;
  31         unsigned high;
  32         for(low=i; low>0; --low)
  33                 if(steps[low].weight>=weight_limit)
  34                         break;
  35         for(high=i; high+1<steps.size(); ++high)
  36                 if(steps[high].weight>=weight_limit)
  37                         break;
  38
  39         if(steps[high].weight)
  40         {
  41                 if(steps[low].weight)
  42                         return (steps[low].speed*(high-i)+steps[high].speed*(i-low))/(high-low);
  43                 else
  44                         return steps[high].speed*i/high;
  45         }
  46         else if(steps[low].weight)
  47                 return steps[low].speed*i/low;
  48         else
  49                 return 0;
  50 }
  51
  52 float SpeedQuantizer::quantize_speed(float speed) const
  53 {
  54         return get_speed(find_speed_step(speed));
  55 }
  56
  57 unsigned SpeedQuantizer::find_speed_step(float speed) const
  58 {
  59         if(speed<=steps[1].speed*0.5)
  60                 return 0;
  61
  62         unsigned low = 0;
  63         unsigned high = 0;
  64         unsigned last = 0;
  65         for(unsigned i=0; (!high && i<steps.size()); ++i)
  66                 if(steps[i].weight>=weight_limit)
  67                 {
  68                         last = i;
  69                         if(steps[i].speed>=speed)
  70                                 high = i;
  71                         else if(steps[i].speed>steps[low].speed)
  72                                 low = i;
  73                 }
  74
  75         if(!high)
  76         {
  77                 unsigned limit = steps.size()/5;
  78                 if(!low)
  79                 {
  80                         if(speed)
  81                                 return limit;
  82                         else
  83                                 return 0;
  84                 }
  85                 return min(min(static_cast<unsigned>(low*speed/steps[low].speed), steps.size()-1), last+limit);
  86         }
  87
  88         float f = (speed-steps[low].speed)/(steps[high].speed-steps[low].speed);
  89         return static_cast<unsigned>(low*(1-f)+high*f+0.5);
  90 }
  91
  92 void SpeedQuantizer::save(list<DataFile::Statement> &st) const
  93 {
  94         for(unsigned i=0; i<steps.size(); ++i)
  95                 if(steps[i].weight)
  96                         st.push_back((DataFile::Statement("step"), i, steps[i].speed, steps[i].weight));
  97 }
  98
  99
 100 SpeedQuantizer::SpeedStep::SpeedStep():
 101         speed(0),
 102         weight(0)
 103 { }
 104
 105 void SpeedQuantizer::SpeedStep::add(float s, float w)
 106 {
 107         speed = (speed*weight+s*w)/(weight+w);
 108         weight = min(weight+w, 300.0f);
 109 }
 110
 111
 112 SpeedQuantizer::Loader::Loader(SpeedQuantizer &q):
 113         DataFile::ObjectLoader<SpeedQuantizer>(q)
 114 {
 115         add("step", &Loader::step);
 116 }
 117
 118 void SpeedQuantizer::Loader::step(unsigned i, float s, float w)
 119 {
 120         if(i>=obj.steps.size())
 121                 return;
 122
 123         obj.steps[i].speed = s;
 124         obj.steps[i].weight = w;
 125 }
 126
 127 } // namespace R2C2