| 30 |
|
r0*((t-2.0)*t+1.0)*t + \ |
| 31 |
|
r1*(t-1.0)*t*t ) |
| 32 |
|
|
| 33 |
< |
double *noise3(), noise3coef(), argument(), frand(); |
| 33 |
> |
static char *noise_name[4] = {"noise3a", "noise3b", "noise3c", "noise3"}; |
| 34 |
> |
static char fnoise_name[] = "fnoise3"; |
| 35 |
> |
static char hermite_name[] = "hermite"; |
| 36 |
|
|
| 37 |
+ |
double *noise3(), fnoise3(), argument(), frand(); |
| 38 |
+ |
|
| 39 |
|
static long xlim[3][2]; |
| 40 |
|
static double xarg[3]; |
| 41 |
|
|
| 43 |
|
|
| 44 |
|
#define frand3(x,y,z) frand(17*(x)+23*(y)+29*(z)) |
| 45 |
|
|
| 42 |
– |
double fnoise3(); |
| 46 |
|
|
| 47 |
< |
|
| 48 |
< |
double |
| 49 |
< |
l_noise3() /* compute 3-dimensional noise function */ |
| 47 |
> |
static double |
| 48 |
> |
l_noise3(nam) /* compute a noise function */ |
| 49 |
> |
register char *nam; |
| 50 |
|
{ |
| 51 |
< |
return(noise3coef(D)); |
| 51 |
> |
register int i; |
| 52 |
> |
double x[3]; |
| 53 |
> |
/* get point */ |
| 54 |
> |
x[0] = argument(1); |
| 55 |
> |
x[1] = argument(2); |
| 56 |
> |
x[2] = argument(3); |
| 57 |
> |
/* make appropriate call */ |
| 58 |
> |
if (nam == fnoise_name) |
| 59 |
> |
return(fnoise3(x)); |
| 60 |
> |
i = 4; |
| 61 |
> |
while (i--) |
| 62 |
> |
if (nam == noise_name[i]) |
| 63 |
> |
return(noise3(x)[i]); |
| 64 |
> |
eputs("Bad call to l_noise3()!\n"); |
| 65 |
> |
quit(1); |
| 66 |
|
} |
| 67 |
|
|
| 68 |
|
|
| 69 |
|
double |
| 70 |
< |
l_noise3a() /* compute x slope of noise function */ |
| 70 |
> |
l_hermite() /* library call for hermite interpolation */ |
| 71 |
|
{ |
| 72 |
< |
return(noise3coef(A)); |
| 72 |
> |
double t; |
| 73 |
> |
|
| 74 |
> |
t = argument(5); |
| 75 |
> |
return( hermite(argument(1), argument(2), |
| 76 |
> |
argument(3), argument(4), t) ); |
| 77 |
|
} |
| 78 |
|
|
| 79 |
|
|
| 80 |
< |
double |
| 60 |
< |
l_noise3b() /* compute y slope of noise function */ |
| 80 |
> |
setnoisefuncs() /* add noise functions to library */ |
| 81 |
|
{ |
| 82 |
< |
return(noise3coef(B)); |
| 63 |
< |
} |
| 82 |
> |
register int i; |
| 83 |
|
|
| 84 |
< |
|
| 85 |
< |
double |
| 86 |
< |
l_noise3c() /* compute z slope of noise function */ |
| 87 |
< |
{ |
| 88 |
< |
return(noise3coef(C)); |
| 84 |
> |
funset(hermite_name, 5, ':', l_hermite); |
| 85 |
> |
funset(fnoise_name, 3, ':', l_noise3); |
| 86 |
> |
i = 4; |
| 87 |
> |
while (i--) |
| 88 |
> |
funset(noise_name[i], 3, ':', l_noise3); |
| 89 |
|
} |
| 90 |
|
|
| 91 |
|
|
| 73 |
– |
double |
| 74 |
– |
l_fnoise3() /* compute fractal noise function */ |
| 75 |
– |
{ |
| 76 |
– |
double x[3]; |
| 77 |
– |
|
| 78 |
– |
x[0] = argument(1); |
| 79 |
– |
x[1] = argument(2); |
| 80 |
– |
x[2] = argument(3); |
| 81 |
– |
|
| 82 |
– |
return(fnoise3(x)); |
| 83 |
– |
} |
| 84 |
– |
|
| 85 |
– |
|
| 86 |
– |
static double |
| 87 |
– |
noise3coef(coef) /* return coefficient of noise function */ |
| 88 |
– |
int coef; |
| 89 |
– |
{ |
| 90 |
– |
double x[3]; |
| 91 |
– |
|
| 92 |
– |
x[0] = argument(1); |
| 93 |
– |
x[1] = argument(2); |
| 94 |
– |
x[2] = argument(3); |
| 95 |
– |
|
| 96 |
– |
return(noise3(x)[coef]); |
| 97 |
– |
} |
| 98 |
– |
|
| 99 |
– |
|
| 92 |
|
double * |
| 93 |
|
noise3(xnew) /* compute the noise function */ |
| 94 |
|
register double xnew[3]; |
| 145 |
|
|
| 146 |
|
|
| 147 |
|
double |
| 156 |
– |
l_hermite() /* library call for hermite interpolation */ |
| 157 |
– |
{ |
| 158 |
– |
double t; |
| 159 |
– |
|
| 160 |
– |
t = argument(5); |
| 161 |
– |
return( hermite(argument(1), argument(2), |
| 162 |
– |
argument(3), argument(4), t) ); |
| 163 |
– |
} |
| 164 |
– |
|
| 165 |
– |
|
| 166 |
– |
double |
| 148 |
|
fnoise3(p) /* compute fractal noise function */ |
| 149 |
|
double p[3]; |
| 150 |
|
{ |
| 151 |
|
double floor(); |
| 152 |
< |
long t[3], v[3], beg[3], s; |
| 152 |
> |
long t[3], v[3], beg[3]; |
| 153 |
|
double fval[8], fc; |
| 154 |
|
int branch; |
| 155 |
+ |
register long s; |
| 156 |
|
register int i, j; |
| 157 |
|
/* get starting cube */ |
| 158 |
|
s = (long)(1.0/EPSILON); |
| 170 |
|
} |
| 171 |
|
/* compute fractal */ |
| 172 |
|
for ( ; ; ) { |
| 173 |
< |
s >>= 1; |
| 173 |
> |
fc = 0.0; |
| 174 |
> |
for (j = 0; j < 8; j++) |
| 175 |
> |
fc += fval[j]; |
| 176 |
> |
fc *= 0.125; |
| 177 |
> |
if ((s >>= 1) == 0) |
| 178 |
> |
return(fc); /* close enough */ |
| 179 |
|
branch = 0; |
| 180 |
|
for (i = 0; i < 3; i++) { /* do center */ |
| 181 |
|
v[i] = beg[i] + s; |
| 183 |
|
branch |= 1<<i; |
| 184 |
|
} |
| 185 |
|
} |
| 199 |
– |
fc = 0.0; |
| 200 |
– |
for (j = 0; j < 8; j++) |
| 201 |
– |
fc += fval[j]; |
| 202 |
– |
fc *= 0.125; |
| 203 |
– |
if (s < 1) |
| 204 |
– |
return(fc); /* close enough */ |
| 186 |
|
fc += s*EPSILON*frand3(v[0],v[1],v[2]); |
| 187 |
|
fval[~branch & 7] = fc; |
| 188 |
|
for (i = 0; i < 3; i++) { /* do faces */ |
