core.cc

   1 /* Synaesthesia - program to display sound graphically
   2    Copyright (C) 1997  Paul Francis Harrison
   3
   4   This program is free software; you can redistribute it and/or modify it
   5   under the terms of the GNU General Public License as published by the
   6   Free Software Foundation; either version 2 of the License, or (at your
   7   option) any later version.
   8
   9   This program is distributed in the hope that it will be useful, but
  10   WITHOUT ANY WARRANTY; without even the implied warranty of
  11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12   General Public License for more details.
  13
  14   You should have received a copy of the GNU General Public License along
  15   with this program; if not, write to the Free Software Foundation, Inc.,
  16   675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18   The author may be contacted at:
  19     pfh@yoyo.cc.monash.edu.au
  20   or
  21     27 Bond St., Mt. Waverley, 3149, Melbourne, Australia
  22 */
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <stdint.h>
  27 #include <math.h>
  28 #include <string.h>
  29 #include "syna.h"
  30
  31 double cosTable[NumSamples], negSinTable[NumSamples];
  32 int bitReverse[NumSamples];
  33 int scaleDown[256];
  34 int maxStarRadius;
  35
  36 int bitReverser(int i) {
  37   int sum=0,j;
  38   for(j=0;j<LogSize;j++) {
  39     sum = (i&1)+sum*2;
  40     i >>= 1;
  41   }
  42   return sum;
  43 }
  44
  45 void fft(double *x,double *y) {
  46   int n2 = NumSamples, n1;
  47   int twoToTheK;
  48   for(twoToTheK=1;twoToTheK<NumSamples;twoToTheK*=2) {
  49     n1 = n2;
  50     n2 /= 2;
  51     for(int j=0;j<n2;j++) {
  52       double c = cosTable[j*twoToTheK&(NumSamples-1)],
  53              s = negSinTable[j*twoToTheK&(NumSamples-1)];
  54       for(int i=j;i<NumSamples;i+=n1) {
  55         int l = i+n2;
  56         double xt = x[i] - x[l];
  57         x[i] = (x[i] + x[l]);
  58         double yt = y[i] - y[l];
  59         y[i] = (y[i] + y[l]);
  60         x[l] = xt*c - yt*s;
  61         y[l] = xt*s + yt*c;
  62       }
  63     }
  64   }
  65 }
  66
  67 void coreInit() {
  68   int i;
  69
  70   for(i=0;i<NumSamples;i++) {
  71     negSinTable[i] = -sin(3.141592*2.0/NumSamples*i);
  72     cosTable[i] = cos(3.141592*2.0/NumSamples*i);
  73     bitReverse[i] = bitReverser(i);
  74   }
  75 }
  76
  77 void setStarSize(double size) {
  78   //int factor = (fadeMode == Flame ? 100 :
  79   //              (fadeMode == Wave ? 150 : 200));
  80
  81   double fadeModeFudge = (fadeMode == Wave ? 0.4 :
  82                 (fadeMode == Flame ? 0.6 : 0.78));
  83
  84   int factor;
  85   if (size > 0.0)
  86     factor = int(exp(log(fadeModeFudge) / (size*8.0))*255);
  87   else
  88     factor = 0;
  89
  90   if (factor > 255) factor = 255;
  91
  92   for(int i=0;i<256;i++)
  93     scaleDown[i] = i*factor>>8;
  94
  95   maxStarRadius = 1;
  96   for(int i=255;i;i = scaleDown[i])
  97     maxStarRadius++;
  98 }
  99
 100 inline void addPixel(int x,int y,int br1,int br2) {
 101   if (x < 0 || x >= outWidth || y < 0 || y >= outHeight) return;
 102
 103   unsigned char *p = output+x*2+y*outWidth*2;
 104   if (p[0] < 255-br1) p[0] += br1; else p[0] = 255;
 105   if (p[1] < 255-br2) p[1] += br2; else p[1] = 255;
 106   //p += lastOutput-output;
 107   //if (p[0] < 255-br1) p[0] += br1; else p[0] = 255;
 108   //if (p[1] < 255-br2) p[1] += br2; else p[1] = 255;
 109 }
 110
 111 inline void addPixelFast(unsigned char *p,int br1,int br2) {
 112   if (p[0] < 255-br1) p[0] += br1; else p[0] = 255;
 113   if (p[1] < 255-br2) p[1] += br2; else p[1] = 255;
 114   //p += lastOutput-output;
 115   //if (p[0] < 255-br1) p[0] += br1; else p[0] = 255;
 116   //if (p[1] < 255-br2) p[1] += br2; else p[1] = 255;
 117 }
 118
 119 void fadeFade() {
 120   register uint32_t *ptr = (uint32_t*)output;
 121   int i = outWidth*outHeight*2/sizeof(uint32_t);
 122   do {
 123     //Bytewize version was: *(ptr++) -= *ptr+(*ptr>>1)>>4;
 124     uint32_t x = *ptr;
 125     if (x)
 126         *(ptr++) = x - ((x & 0xf0f0f0f0ul) >> 4) - ((x & 0xe0e0e0e0ul) >> 5);
 127     else
 128       ptr++;
 129   } while(--i > 0);
 130 }
 131
 132 inline unsigned char getPixel(int x,int y,int where) {
 133   if (x < 0 || y < 0 || x >= outWidth || y >= outHeight) return 0;
 134   return lastOutput[where];
 135 }
 136
 137 inline void fadePixelWave(int x,int y,int where,int step) {
 138   short j =
 139     ( short(getPixel(x-1,y,where-2))+
 140     getPixel(x+1,y,where+2)+
 141     getPixel(x,y-1,where-step)+
 142     getPixel(x,y+1,where+step)
 143     >> 2)
 144     +lastOutput[where];
 145   if (!j) { output[where] = 0; return; }
 146   j = j
 147     -lastLastOutput[where]
 148     -1;
 149   if (j < 0) output[where] = 0;
 150   else if (j & (255*256)) output[where] = 255;
 151   else output[where] = j;
 152 }
 153
 154 void fadeWave() {
 155   unsigned short *t = lastLastOutputBmp.data;
 156   lastLastOutputBmp.data = lastOutputBmp.data;
 157   lastOutputBmp.data = outputBmp.data;
 158   outputBmp.data = t;
 159
 160   int x,y,i,j,start,end;
 161   int step = outWidth*2;
 162   for(x=0,i=0,j=outWidth*(outHeight-1)*2;x<outWidth;x++,i+=2,j+=2) {
 163     fadePixelWave(x,0,i,step);
 164     fadePixelWave(x,0,i+1,step);
 165     fadePixelWave(x,outHeight-1,j,step);
 166     fadePixelWave(x,outHeight-1,j+1,step);
 167   }
 168
 169   for(y=1,i=outWidth*2,j=outWidth*4-2;y<outHeight;y++,i+=step,j+=step) {
 170     fadePixelWave(0,y,i,step);
 171     fadePixelWave(0,y,i+1,step);
 172     fadePixelWave(outWidth-1,y,j,step);
 173     fadePixelWave(outWidth-1,y,j+1,step);
 174   }
 175
 176   for(y=1,
 177       start=outWidth*2+2,
 178       end=outWidth*4-2; y<outHeight-1; y++,start+=step,end+=step) {
 179     int i = start;
 180     do {
 181       short j =
 182         ( short(lastOutput[i-2])+
 183         lastOutput[i+2]+
 184         lastOutput[i-step]+
 185         lastOutput[i+step]
 186         >> 2)
 187         +lastOutput[i];
 188       if (!j) {
 189         output[i] = 0;
 190       } else {
 191         j = j
 192           -lastLastOutput[i]
 193           -1;
 194         if (j < 0) output[i] = 0;
 195         else if (j & (255*256)) output[i] = 255;
 196         else output[i] = j;
 197       }
 198     } while(++i < end);
 199   }
 200 }
 201
 202 inline void fadePixelHeat(int x,int y,int where,int step) {
 203   short j =
 204     ( short(getPixel(x-1,y,where-2))+
 205     getPixel(x+1,y,where+2)+
 206     getPixel(x,y-1,where-step)+
 207     getPixel(x,y+1,where+step)
 208     >> 2)
 209     +lastOutput[where];
 210   if (!j) { output[where] = 0; return; }
 211   j = j
 212     -lastLastOutput[where]
 213     -1;
 214   if (j < 0) output[where] = 0;
 215   else if (j & (255*256)) output[where] = 255;
 216   else output[where] = j;
 217 }
 218
 219 void fadeHeat() {
 220   unsigned short *t = lastLastOutputBmp.data;
 221   lastLastOutputBmp.data = lastOutputBmp.data;
 222   lastOutputBmp.data = outputBmp.data;
 223   outputBmp.data = t;
 224
 225   int x,y,i,j,start,end;
 226   int step = outWidth*2;
 227   for(x=0,i=0,j=outWidth*(outHeight-1)*2;x<outWidth;x++,i+=2,j+=2) {
 228     fadePixelHeat(x,0,i,step);
 229     fadePixelHeat(x,0,i+1,step);
 230     fadePixelHeat(x,outHeight-1,j,step);
 231     fadePixelHeat(x,outHeight-1,j+1,step);
 232   }
 233
 234   for(y=1,i=outWidth*2,j=outWidth*4-2;y<outHeight;y++,i+=step,j+=step) {
 235     fadePixelHeat(0,y,i,step);
 236     fadePixelHeat(0,y,i+1,step);
 237     fadePixelHeat(outWidth-1,y,j,step);
 238     fadePixelHeat(outWidth-1,y,j+1,step);
 239   }
 240
 241   for(y=1,
 242       start=outWidth*2+2,
 243       end=outWidth*4-2; y<outHeight-1; y++,start+=step,end+=step) {
 244     int i = start;
 245     do {
 246       short j =
 247         ( short(lastOutput[i-2])+
 248         lastOutput[i+2]+
 249         +lastOutput[i-step]
 250         +lastOutput[i+step]
 251         >> 2)
 252         +lastOutput[i];
 253       if (!j) {
 254         output[i] = 0;
 255       } else {
 256         j = j
 257           -lastLastOutput[i]
 258           +(lastLastOutput[i]
 259            -lastOutput[i]>>2)
 260           -1;
 261         if (j < 0) output[i] = 0;
 262         else if (j & (255*256)) output[i] = 255;
 263         else output[i] = j;
 264       }
 265     } while(++i < end);
 266   }
 267 }
 268
 269 void fade() {
 270   switch(fadeMode) {
 271     case Stars :
 272       fadeFade();
 273       break;
 274     case Flame :
 275       fadeHeat();
 276       break;
 277     case Wave :
 278       fadeWave();
 279       break;
 280     default:
 281       break;
 282   }
 283 }
 284
 285 int coreGo() {
 286   double x[NumSamples], y[NumSamples];
 287   double a[NumSamples], b[NumSamples];
 288   double energy;
 289   int clarity[NumSamples]; //Surround sound
 290   int i,j,k;
 291
 292   int brightFactor = int(Brightness * brightnessTwiddler /(starSize+0.01));
 293
 294   if (-1 == getNextFragment())
 295     return -1;
 296
 297   for(i=0;i<NumSamples;i++) {
 298     x[i] = data[i*2];
 299     y[i] = data[i*2+1];
 300   }
 301
 302   fft(x,y);
 303
 304   energy = 0.0;
 305
 306   for(i=0 +1;i<NumSamples/2;i++) {
 307     double x1 = x[bitReverse[i]],
 308            y1 = y[bitReverse[i]],
 309            x2 = x[bitReverse[NumSamples-i]],
 310            y2 = y[bitReverse[NumSamples-i]],
 311            aa,bb;
 312     a[i] = sqrt(aa= (x1+x2)*(x1+x2) + (y1-y2)*(y1-y2) );
 313     b[i] = sqrt(bb= (x1-x2)*(x1-x2) + (y1+y2)*(y1+y2) );
 314     if (aa+bb != 0.0)
 315       clarity[i] = (int)(
 316         ( (x1+x2) * (x1-x2) + (y1+y2) * (y1-y2) )/(aa+bb) * 256 );
 317     else
 318       clarity[i] = 0;
 319
 320     energy += (aa+bb)*i*i;
 321   }
 322
 323   energy = sqrt(energy/NumSamples)/65536.0;
 324
 325   //int heightFactor = NumSamples/2 / outHeight + 1;
 326   //int actualHeight = NumSamples/2/heightFactor;
 327   //int heightAdd = outHeight + actualHeight >> 1;
 328
 329   /* Correct for window size */
 330   //double brightFactor2 = (brightFactor/65536.0/NumSamples)*
 331   //    sqrt(actualHeight*outWidth/(320.0*200.0));
 332   double brightFactor2 = (brightFactor/65536.0/NumSamples)*
 333       sqrt(outHeight*outWidth/(320.0*200.0));
 334
 335   // Some more arbitrary constants,
 336   // this time for dynamic range compression of the display
 337   // (breath slowly, relax, please don't hunt me down and kill me)
 338   static double energy_avg = 80.0;
 339   energy_avg = energy_avg*0.95 + energy*0.05;
 340   if (energy_avg > 0.0)
 341     brightFactor2 *= 80.0/(energy_avg + 5.0);
 342
 343   for(i=1;i<NumSamples/2;i++) {
 344     //int h = (int)( b[i]*280 / (a[i]+b[i]+0.0001)+20 );
 345     if (a[i] > 0 || b[i] > 0) {
 346       int h = (int)( b[i]*outWidth / (a[i]+b[i]) );
 347       int br1, br2, br = (int)(
 348           (a[i]+b[i])*i*brightFactor2 );
 349       br1 = br*(clarity[i]+128)>>8;
 350       br2 = br*(128-clarity[i])>>8;
 351
 352       if (br1 < 0) br1 = 0; else if (br1 > 255) br1 = 255;
 353       if (br2 < 0) br2 = 0; else if (br2 > 255) br2 = 255;
 354
 355       int px = h,
 356           py = outHeight-i*outHeight/(NumSamples/2);
 357           //was heightAdd - i / heightFactor;
 358
 359       if (pointsAreDiamonds) {
 360         addPixel(px,py,br1,br2);
 361         br1=scaleDown[br1];br2=scaleDown[br2];
 362
 363         //TODO: Use addpixelfast
 364         for(j=1;br1>0||br2>0;j++,br1=scaleDown[br1],br2=scaleDown[br2]) {
 365           for(k=0;k<j;k++) {
 366             addPixel(px-j+k,py-k,br1,br2);
 367             addPixel(px+k,py-j+k,br1,br2);
 368             addPixel(px+j-k,py+k,br1,br2);
 369             addPixel(px-k,py+j-k,br1,br2);
 370           }
 371         }
 372       } else {
 373         if (px < maxStarRadius || py < maxStarRadius ||
 374             px > outWidth-maxStarRadius || py > outHeight-maxStarRadius) {
 375           addPixel(px,py,br1,br2);
 376           for(j=1;br1>0||br2>0;j++,br1=scaleDown[br1],br2=scaleDown[br2]) {
 377             addPixel(px+j,py,br1,br2);
 378             addPixel(px,py+j,br1,br2);
 379             addPixel(px-j,py,br1,br2);
 380             addPixel(px,py-j,br1,br2);
 381           }
 382         } else {
 383           unsigned char *p = output+px*2+py*outWidth*2, *p1=p, *p2=p, *p3=p, *p4=p;
 384           addPixelFast(p,br1,br2);
 385           for(;br1>0||br2>0;br1=scaleDown[br1],br2=scaleDown[br2]) {
 386             p1 += 2;
 387             addPixelFast(p1,br1,br2);
 388             p2 -= 2;
 389             addPixelFast(p2,br1,br2);
 390             p3 += outWidth*2;
 391             addPixelFast(p3,br1,br2);
 392             p4 -= outWidth*2;
 393             addPixelFast(p4,br1,br2);
 394           }
 395         }
 396       }
 397     }
 398   }
 399   return 0;
 400 }