298 |
|
|
299 |
|
SCANBAR *rootbar; /* root scan bar (lowest resolution) */ |
300 |
|
|
301 |
< |
float *inpacuD; /* input acuity data (cycles/degree) */ |
301 |
> |
float *inpacuD = NULL; /* input acuity data (cycles/degree) */ |
302 |
|
|
303 |
|
#define tsampr(x,y) inpacuD[(y)*fvxr+(x)] |
304 |
|
|
364 |
|
double dx, dy; |
365 |
|
int ix, iy; |
366 |
|
register int x; |
367 |
+ |
|
368 |
+ |
if (inpacuD == NULL) |
369 |
+ |
return; |
370 |
|
/* compute foveal y position */ |
371 |
|
iy = dy = (y+.5)/numscans(&inpres)*fvyr - .5; |
372 |
|
while (iy >= fvyr-1) iy--; |
491 |
|
} |
492 |
|
|
493 |
|
|
494 |
< |
extern void |
494 |
> |
extern int |
495 |
|
initacuity(void) /* initialize variable acuity sampling */ |
496 |
|
{ |
497 |
|
FVECT diffx, diffy, cp; |
498 |
|
double omega, maxsr; |
499 |
|
register int x, y, i; |
500 |
+ |
|
501 |
+ |
if (fvxr < 3 || fvyr < 3) |
502 |
+ |
return(0); /* too small to work with */ |
503 |
|
|
504 |
|
compraydir(); /* compute ray directions */ |
505 |
|
|
536 |
|
} |
537 |
|
/* initialize with next power of two */ |
538 |
|
rootbar = sballoc((int)(log(maxsr)/log(2.))+1, 2, scanlen(&inpres)); |
539 |
+ |
return(1); |
540 |
|
} |