/*# proc: slope_left_above - determines the slope of the left side of a character# proc:                    piece touching above the line.# proc: slope_left_below - determines the slope of the left side of a character# proc:                    piece touching below the line.# proc: slope_right_above - determines the slope of the right side of a character# proc:                     piece touching above the line.# proc: slope_right_below - determines the slope of the right side of a character# proc:                     piece touching below the line.*/#include <stdio.h>#include <values.h>#include <defs.h>#include <rmline.h>#include <mytrace.h>/***************************************************************************//* slope_left_above - determines the slope of the left side of a character *//* piece touching above the line.                                          *//***************************************************************************/float slope_left_above(sx, sy, slimit, slen, cdata, w, h)int sx, sy, slimit, slen;unsigned char *cdata;int w, h;{   unsigned char *cptr;   int i, x, y, cx, ox;   int dxs, n, diff;   float m;   my_trace("entered slope_left_above\n");   x = sx;   y = sy;   cptr = cdata + (y * w) + x;   /* if starting on a white pixel, look right for black */   if(*cptr == WHITE_PIX){      if((cx = find_pix_east(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND){         /* maybe a problem, but call it vertical for now */         my_trace("slope not found, assuming vertical\n");         my_trace("finished slope_left_above\n");         return(MAXFLOAT);      }      else{         x = cx;         cptr = cdata + (y * w) + x;      }   }   dxs = 0;   n = 0;   /* trace the character edge */   for(i = 0; i < slen; i++){      ox = x;      /* move up a scanline */      y--;      if(y < 0)         /* if traced off the image, then stop */         break;      cptr -= w;      /* if white pixel, look right for black */      if(*cptr == WHITE_PIX){         if((cx = find_pix_east(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;      }      else{         /* if black pixel, look left for white */         if((cx = find_pix_west(WHITE_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;         else            /* if white pixel found, then jump back one to black */            cx++;      }      /* if still on the image ... */      x = cx;      cptr = cdata + (y * w) + x;      /* compute delta in x */      diff = (ox - x);      /* if jump is too big, then stop */      if(abs(diff) > slimit)         break;      else{         dxs += (ox - x);         n++;      }   }   if(dxs == 0)      m = MAXFLOAT;   else      m = n / (float)dxs;   my_trace("finished slope_left_above\n");   return(m);}/***************************************************************************//* slope_left_below - determines the slope of the left side of a char      *//* piece touching below the line.                                          *//***************************************************************************/float slope_left_below(sx, sy, slimit, slen, cdata, w, h)int sx, sy, slimit, slen;unsigned char *cdata;int w, h;{   unsigned char *cptr;   int i, x, y, cx, ox;   int dxs, n, diff;   float m;   my_trace("entered slope_left_below\n");   x = sx;   y = sy;   cptr = cdata + (y * w) + x;   /* if starting on a white pixel, look right for black */   if(*cptr == WHITE_PIX){      if((cx = find_pix_east(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND){         /* maybe a problem, but call it vertical for now */         my_trace("slope not found, assuming vertical\n");         my_trace("finished slope_left_below\n");         return(MAXFLOAT);      }      else{         x = cx;         cptr = cdata + (y * w) + x;      }   }   dxs = 0;   n = 0;   /* trace character edge */   for(i = 0; i < slen; i++){      ox = x;      /* move down a scanline */      y++;      if(y >= h)         /* if traced off the image, then stop */         break;      cptr += w;      /* if white pixel, look right for black */      if(*cptr == WHITE_PIX){         if((cx = find_pix_east(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;      }      else{         /* if black pixel, look left for white */         if((cx = find_pix_west(WHITE_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;         else            /* if white pixel found, then jump back one to black */            cx++;      }      /* if still on the image ... */      x = cx;      cptr = cdata + (y * w) + x;      /* compute delta in x */      diff = (ox - x);      /* if jump is too big, then stop */      if(abs(diff) > slimit)         break;      else{         dxs += (ox - x);         n++;      }   }   if(dxs == 0)      m = MAXFLOAT;   else      m = (-1.0*n) / (float)dxs;   my_trace("finished slope_left_below\n");   return(m);}/***************************************************************************//* slope_right_above - determines the slope of the right side of a char    *//* piece touching above the line.                                          *//***************************************************************************/float slope_right_above(sx, sy, slimit, slen, cdata, w, h)int sx, sy, slimit, slen;unsigned char *cdata;int w, h;{   unsigned char *cptr;   int i, x, y, cx, ox;   int dxs, n, diff;   float m;   my_trace("entered slope_right_above\n");   x = sx;   y = sy;   cptr = cdata + (y * w) + x;   /* if starting on a white pixel, look left for black */   if(*cptr == WHITE_PIX){      if((cx = find_pix_west(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND){         /* maybe a problem, but call it vertical for now */         my_trace("slope not found, assuming vertical\n");         my_trace("finished slope_right_above\n");         return(MAXFLOAT);      }      else{         x = cx;         cptr = cdata + (y * w) + x;      }   }   dxs = 0;   n = 0;   /* trace character edge */   for(i = 0; i < slen; i++){      ox = x;      /* move up a scanline */      y--;      if(y < 0)         /* if traced off the image, then stop */         break;      cptr -= w;      /* if white pixel, look left for black */      if(*cptr == WHITE_PIX){         if((cx = find_pix_west(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;      }      else{         /* if black pixel, look right for white */         if((cx = find_pix_east(WHITE_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;         else            /* if white pixel found, then jump back one to black */            cx--;      }      /* if still on the image ... */      x = cx;      cptr = cdata + (y * w) + x;      /* compute delta in x */      diff = (ox - x);      /* if jump is too big, then stop */      if(abs(diff) > slimit)         break;      else{         dxs += (ox - x);         n++;      }   }   if(dxs == 0)      m = MAXFLOAT;   else      m = n / (float)dxs;   my_trace("finished slope_right_above\n");   return(m);}/***************************************************************************//* slope_right_below - determines the slope of the right side of a char    *//* piece touching below the line.                                          *//***************************************************************************/float slope_right_below(sx, sy, slimit, slen, cdata, w, h)int sx, sy, slimit, slen;unsigned char *cdata;int w, h;{   unsigned char *cptr;   int i, x, y, cx, ox;   int dxs, n, diff;   float m;   my_trace("entered slope_right_below\n");   x = sx;   y = sy;   cptr = cdata + (y * w) + x;   /* if starting on a white pixel, look left for black */   if(*cptr == WHITE_PIX){      if((cx = find_pix_west(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND){         /* maybe a problem, but call it vertical for now */         my_trace("slope not found, assuming vertical\n");         my_trace("finished slope_right_below\n");         return(MAXFLOAT);      }      else{         x = cx;         cptr = cdata + (y * w) + x;      }   }   dxs = 0;   n = 0;   /* trace character edge */   for(i = 0; i < slen; i++){      ox = x;      /* move down a scanline */      y++;      if(y >= h)         /* if traced off the image, then stop */         break;      cptr += w;      /* if white pixel, look left for black */      if(*cptr == WHITE_PIX){         if((cx = find_pix_west(BLACK_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;      }      else{         /* if black pixel, look right for white */         if((cx = find_pix_east(WHITE_PIX, x, y, cdata, w, h)) == NOT_FOUND)            /* if traced off the image, then stop */            break;         else            /* if white pixel found, then jump back one to black */            cx--;      }      /* if still on the image ... */      x = cx;      cptr = cdata + (y * w) + x;      /* compute delta in x */      diff = (ox - x);      if(abs(diff) > slimit)         break;      /* if jump is too big, then stop */      else{         dxs += (ox - x);         n++;      }   }   if(dxs == 0)      m = MAXFLOAT;   else      m = (-1.0*n) / (float)dxs;   my_trace("finished slope_right_below\n");   return(m);}