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C/C++ Source or Header  |  2000-12-10  |  4KB  |  233 lines
  1.  
  2. #include <string.h>
  3. #include <stdlib.h>
  4. #include <assert.h>
  5. #include <math.h>
  6. #include "C:\progra~1\zik\buzz\dev\MachineInterface.h"
  7.  
  8. double const Silence = log(1.0 / 32768);
  9.  
  10.  
  11. CMachineParameter const parab0 = 
  12. { 
  13.     pt_word,                                        // type
  14.     "b0",
  15.     "Order-0 mathematical term (~DryThru)",                        // description
  16.     0,                                                // MinValue    
  17.     0xfffe,                                            // MaxValue
  18.     0xffff,                                            // NoValue
  19.     MPF_STATE,                                        // Flags
  20.     0xc000,
  21. };
  22. CMachineParameter const paraa1 = 
  23. { 
  24.     pt_word,                                        // type
  25.     "a1 % 1+a2",
  26.     "First order mathematical term (~Cutoff)",                        // description
  27.     0,                                                // MinValue    
  28.     0xfffe,                                            // MaxValue
  29.     0xffff,                                            // NoValue
  30.     MPF_STATE,                                        // Flags
  31.     0xfffe,
  32. };
  33. CMachineParameter const parab1 = 
  34. { 
  35.     pt_word,                                        // type
  36.     "b1",
  37.     "First order mathematical term (~filter mode)",                        // description
  38.     0,                                                // MinValue    
  39.     0xfffe,                                            // MaxValue
  40.     0xffff,                                            // NoValue
  41.     MPF_STATE,                                        // Flags
  42.     0x7fff,
  43. };
  44. CMachineParameter const paraa2 = 
  45. { 
  46.     pt_word,                                        // type
  47.     "a2",
  48.     "Second order mathematical term",                        // description
  49.     0,                                                // MinValue    
  50.     0xfffe,                                            // MaxValue
  51.     0xffff,                                            // NoValue
  52.     MPF_STATE,                                        // Flags
  53.     0x7fff,
  54. };
  55. CMachineParameter const parab2 = 
  56. { 
  57.     pt_word,                                        // type
  58.     "b2",
  59.     "Second order mathematical term",                        // description
  60.     0,                                                // MinValue    
  61.     0xfffe,                                            // MaxValue
  62.     0xffff,                                            // NoValue
  63.     MPF_STATE,                                        // Flags
  64.     0x4000,
  65. };
  66.  
  67. CMachineParameter const *pParameters[] = 
  68. { 
  69.     // global
  70.     ¶b0,
  71.     ¶a1,
  72.     ¶b1,
  73.     ¶a2,
  74.     ¶b2,
  75.     
  76. };
  77.  
  78. #pragma pack(1)        
  79.  
  80. class gvals
  81. {
  82. public:
  83.     word b0,a1,b1,a2,b2;
  84. };
  85.  
  86. #pragma pack()
  87.  
  88. CMachineInfo const MacInfo = 
  89. {
  90.     MT_EFFECT,                                // type
  91.     MI_VERSION,    
  92.     0,                                        // flags
  93.     0,                                        // min tracks
  94.     0,                                        // max tracks
  95.     5,                                        // numGlobalParameters
  96.     0,                                    // numTrackParameters
  97.     pParameters,
  98.     0,
  99.     NULL,
  100. #ifdef _DEBUG
  101.     "Q Zfilter (Debug build)",        // name
  102. #else
  103.     "Q Zfilter",                    // name
  104. #endif
  105.     "Z",                                    // short name
  106.     "Q",                        // author
  107.     NULL
  108. };
  109.  
  110.  
  111. class mi : public CMachineInterface
  112. {
  113. public:
  114.     mi();
  115.     virtual ~mi();
  116.  
  117.     virtual void Init(CMachineDataInput * const pi);
  118.     virtual void Tick();
  119.     virtual bool Work(float *psamples, int numsamples, int const mode);
  120.     virtual char const *DescribeValue(int const param, int const value);
  121.  
  122. private:
  123.     float b0,a1,b1,a2,b2;
  124.     
  125.     gvals gval;
  126.     float x1,x2,y1,y2;
  127.     
  128. };
  129.  
  130. DLL_EXPORTS
  131.  
  132. mi::mi()
  133. {
  134.     GlobalVals = &gval;
  135. }
  136.  
  137. mi::~mi()
  138. {
  139. }
  140.  
  141. void mi::Init(CMachineDataInput * const pi)
  142. {
  143.     x1=x2=y1=y2=0;
  144.     a2=0;
  145.     b2=0;
  146.     b0=1;
  147.     b1=-1;
  148.     a1=(float)0x7FFF/0x8000;
  149. } 
  150.  
  151. void mi::Tick()
  152. {
  153.     
  154.     if (gval.b0 != parab0.NoValue)
  155.         b0= (float)(gval.b0-0x7FFF)/0x4000;
  156.     if (gval.a1 != paraa1.NoValue)
  157.         a1= (float)(gval.a1-0x7FFF)*(1+a2)/0x8000;
  158.     if (gval.b1 != parab1.NoValue)
  159.         b1= (float)(gval.b1-0x7FFF)/0x4000;
  160.     if (gval.a2 != paraa2.NoValue)
  161.     {
  162.         a1= a1*(float)gval.a2/0x8000/(1+a2);
  163.         a2= (float)(gval.a2-0x7FFF)/0x8000;
  164.     }
  165.         
  166.     if (gval.b2 != parab2.NoValue)
  167.         b2= (float)(gval.b2-0x7FFF)/0x4000;
  168.         
  169. }
  170.  
  171. char const *mi::DescribeValue(int const param, int const value)
  172. {
  173.     static char txt[16];
  174.  
  175.     switch(param)
  176.     {
  177.     case 0:
  178.         sprintf(txt, "%.4f", b0 );
  179.         break;
  180.     case 1:
  181.         sprintf(txt, "%.4f", a1/(1+a2) );
  182.         break;
  183.     case 2:
  184.         sprintf(txt, "%.4f", b1 );
  185.         break;
  186.     case 3:
  187.         sprintf(txt, "%.4f", a2);
  188.         break;
  189.     case 4:
  190.         sprintf(txt, "%.4f", b2 );
  191.         break;
  192.     default:
  193.         return NULL;
  194.     }
  195.  
  196.     return txt;
  197. }
  198.  
  199. bool mi::Work(float *psamples, int numsamples, int const mode)
  200. {
  201.  
  202.     if (mode == WM_NOIO)
  203.         return false;
  204.     
  205.  
  206.  
  207.     do 
  208.     {
  209.         float x0=*psamples;
  210.  
  211.         if (mode & WM_WRITE)
  212.         {
  213.             *psamples=b0*x0+b1*x1+b2*x2-a1*y1-a2*y2;
  214.             y2=y1;
  215.             y1=*psamples;
  216.         }
  217.         psamples++;
  218.         x2=x1;
  219.         if (mode & WM_READ)
  220.             x1=x0;
  221.         else
  222.             x1=0;    
  223.         
  224.     } while(--numsamples);
  225.  
  226.     
  227.     if (mode & WM_WRITE)
  228.         return true;
  229.     return false;
  230. }
  231.  
  232.  
  233.