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optimize mpfr implementation

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josch 2013-06-27 15:57:21 +02:00
parent faf340ecab
commit be7342b0cf
1 changed files with 27 additions and 63 deletions
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90
mandel_mpfr.c
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@ -11,15 +11,11 @@ int main(int argc, char **argv) {
fprintf(stderr, "usage: %s width height centerx centery magnification", argv[0]);
return 1;
}
mpfr_t temp1, temp2;
mpfr_t temp1;
mpfr_init2(temp1, 300);
mpfr_init2(temp2, 300);
long double eps = 1e-17;
mpfr_t Q1LOG2, LOG2;
mpfr_init2(Q1LOG2, 300);
mpfr_init2(LOG2, 300);
mpfr_set_str(Q1LOG2, "1.44269504088896340735992468100189213742664595415299", 10, MPFR_RNDN);
mpfr_set_str(LOG2, "0.69314718055994530941723212145817656807550013436026", 10, MPFR_RNDN);
double eps = 1e-17;
double Q1LOG2 = 1.44269504088896340735992468100189213742664595415299;
double LOG2 = 0.69314718055994530941723212145817656807550013436026;
unsigned int width = atoi(argv[1]);
unsigned int height = atoi(argv[2]);
char* image = malloc(width*height*3);
@ -29,21 +25,8 @@ int main(int argc, char **argv) {
mpfr_init2(centery, 300);
mpfr_set_str(centerx, argv[3], 10, MPFR_RNDN);
mpfr_set_str(centery, argv[4], 10, MPFR_RNDN);
/*mpfr_set_d(centerx, -0.7436438870371587, MPFR_RNDN);
mpfr_add_d(centerx, centerx, -3.628952515063387E-17, MPFR_RNDN);
mpfr_set_d(centery, 0.13182590420531198, MPFR_RNDN);
mpfr_add_d(centery, centery, -1.2892807754956678E-17, MPFR_RNDN);
mpfr_out_str(stderr, 10, 0, centerx, MPFR_RNDN);
fputs("\n", stderr);
mpfr_out_str(stderr, 10, 0, centery, MPFR_RNDN);
fputs("\n", stderr);*/
double bailout = 4; // the distance must not be greater than 2 (4 = 2*2)
mpfr_t logLogBailout;
mpfr_init2(logLogBailout, 300);
// logLogBailout = log(log(bailout));
mpfr_set_d(logLogBailout, bailout, MPFR_RNDN);
mpfr_log(logLogBailout, logLogBailout, MPFR_RNDN);
mpfr_log(logLogBailout, logLogBailout, MPFR_RNDN);
double logLogBailout = log(log(bailout));
mpfr_t magn;
mpfr_init2(magn, 300);
mpfr_set_str(magn, argv[5], 10, MPFR_RNDN);
@ -70,21 +53,16 @@ int main(int argc, char **argv) {
mpfr_div_ui(temp1, temp1, width, MPFR_RNDN);
mpfr_mul(y2, y2, temp1, MPFR_RNDN);
mpfr_add(y2, y2, centery, MPFR_RNDN);
mpfr_t px, py, zx, zy, xx, yy, r, c;
mpfr_t px, py, zx, zy, xx, yy;
mpfr_init2(px, 300);
mpfr_init2(py, 300);
mpfr_init2(zx, 300);
mpfr_init2(zy, 300);
mpfr_init2(xx, 300);
mpfr_init2(yy, 300);
mpfr_init2(r, 300);
mpfr_init2(c, 300);
int idx;
int imgidx = 0;
mpfr_t hx, hy, d;
mpfr_init2(hx, 300);
mpfr_init2(hy, 300);
mpfr_init2(d, 300);
unsigned int idx;
unsigned int imgidx = 0;
double hx, hy, d;
int foundperiods = 0;
for (y = 0; y < height; y++) {
for (x = 0; x < width; x++) {
@ -104,8 +82,9 @@ int main(int argc, char **argv) {
bool inside = true;
int check = 3;
int whenupdate = 10;
mpfr_set_d(hx, 0, MPFR_RNDN);
mpfr_set_d(hy, 0, MPFR_RNDN);
hx = 0;
hy = 0;
double zxd, zyd;
for (i = 1; i <= maxiter; i++) {
//for (i = 1; i <= 50000; i++) {
//xx = zx * zx;
@ -128,14 +107,12 @@ int main(int argc, char **argv) {
mpfr_add(zx, zx, px, MPFR_RNDN);
// period checking
// d = zx - hx;
mpfr_sub(d, zx, hx, MPFR_RNDN);
mpfr_abs(d, d, MPFR_RNDN);
if (mpfr_cmp_d(d, eps) < 0) {
// d = zy - hy;
mpfr_sub(d, zy, hy, MPFR_RNDN);
mpfr_abs(d, d, MPFR_RNDN);
if (mpfr_cmp_d(d, eps) < 0) {
zxd = mpfr_get_d(zx, MPFR_RNDN);
d = zxd - hx;
if (d > 0.0 ? d < eps : d > -eps) {
zyd = mpfr_get_d(zy, MPFR_RNDN);
d = zyd - hy;
if (d > 0.0 ? d < eps : d > -eps) {
// Period found.
foundperiods++;
break;
@ -148,8 +125,10 @@ int main(int argc, char **argv) {
check++;
}
// period = 0;
mpfr_set(hx, zx, MPFR_RNDN);
mpfr_set(hy, zy, MPFR_RNDN);
zxd = mpfr_get_d(zx, MPFR_RNDN);
zyd = mpfr_get_d(zy, MPFR_RNDN);
hx = zxd;
hy = zyd;
}
}
@ -158,26 +137,11 @@ int main(int argc, char **argv) {
image[imgidx++] = 0;
image[imgidx++] = 0;
} else {
//r = sqrtl(zx*zx + zy*zy);
mpfr_mul(temp1, zx, zx, MPFR_RNDN);
mpfr_mul(temp2, zy, zy, MPFR_RNDN);
mpfr_add(temp1, temp1, temp2, MPFR_RNDN);
mpfr_sqrt(r, temp1, MPFR_RNDN);
//c = i - 1.28 + (logLogBailout - logl(logl(r))) * Q1LOG2;
mpfr_log(r, r, MPFR_RNDN);
mpfr_log(r, r, MPFR_RNDN);
mpfr_sub(c, logLogBailout, r, MPFR_RNDN);
mpfr_mul(c, c, Q1LOG2, MPFR_RNDN);
mpfr_add_d(c, c, i - 1.28, MPFR_RNDN);
//idx = fmodl((logl(c/64+1)/LOG2+0.45), 1)*GRADIENTLENGTH + 0.5;
mpfr_div_ui(c, c, 64, MPFR_RNDN);
mpfr_add_ui(c, c, 1, MPFR_RNDN);
mpfr_log(c, c, MPFR_RNDN);
mpfr_div(c, c, LOG2, MPFR_RNDN);
mpfr_add_d(c, c, 0.45, MPFR_RNDN);
mpfr_frac(c, c, MPFR_RNDN);
mpfr_mul_d(c, c, GRADIENTLENGTH, MPFR_RNDN);
idx = mpfr_get_ui(c, MPFR_RNDN);
zxd = mpfr_get_d(zx, MPFR_RNDN);
zyd = mpfr_get_d(zy, MPFR_RNDN);
double r = sqrt(zxd*zxd + zyd*zyd);
double c = i - 1.28 + (logLogBailout - log(log(r))) * Q1LOG2;
idx = fmod((log(c/64+1)/LOG2+0.45), 1)*GRADIENTLENGTH + 0.5;
image[imgidx++] = colors[idx][0];
image[imgidx++] = colors[idx][1];
image[imgidx++] = colors[idx][2];