diff options
Diffstat (limited to 'generator')
| -rw-r--r-- | generator/ppmforge.c | 191 |
1 files changed, 77 insertions, 114 deletions
diff --git a/generator/ppmforge.c b/generator/ppmforge.c index 47f9390e..e32d2b59 100644 --- a/generator/ppmforge.c +++ b/generator/ppmforge.c @@ -90,6 +90,7 @@ struct CmdlineInfo { float ice; int saturation; unsigned int seed; + unsigned int seedSpec; int stars; unsigned int starsSpec; unsigned int width; @@ -335,76 +336,38 @@ fourn(double * const data, nprev *= n; } } -#undef SWAP -struct Gauss { - struct pm_randSt randSt; - unsigned int nrand; /* Gauss() sample count */ - double arand; - double gaussadd; - double gaussfac; -}; - - -static void -initgauss(struct Gauss * const gaussP, - unsigned int const seed) { +static double +cast(double const low, + double const high, + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- - Initialize random number generators. - - As given in Peitgen & Saupe, page 77. + A random number in the range ['low', 'high']. -----------------------------------------------------------------------------*/ - gaussP->nrand = 4; - - /* Range of random generator */ - gaussP->arand = pow(2.0, 15.0) - 1.0; - gaussP->gaussadd = sqrt(3.0 * gaussP->nrand); - gaussP->gaussfac = 2 * gaussP->gaussadd / (gaussP->nrand * gaussP->arand); + return (low + (high - low) * pm_drand(randStP)); - pm_randinit(&gaussP->randSt); - pm_srand(&gaussP->randSt, seed); } static double -gauss(struct Gauss * const gaussP) { +randPhase(struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- - A Gaussian random number. - - As given in Peitgen & Saupe, page 77. + A random number in the range [0, 2 * PI). -----------------------------------------------------------------------------*/ - unsigned int i; - double sum; - - for (i = 1, sum = 0.0; i <= gaussP->nrand; ++i) { - sum += (pm_rand(&gaussP->randSt) & 0x7FFF); - } - return gaussP->gaussfac * sum - gaussP->gaussadd; -} - - - -static double -cast(double const low, - double const high, - struct Gauss * const gaussP) { - - return - low + - ((high-low) * ((pm_rand(&gaussP->randSt) & 0x7FFF) / gaussP->arand)); + return (2.0 * M_PI * pm_drand1(randStP)); } static void -spectralsynth(double ** const aP, - unsigned int const n, - double const h, - struct Gauss * const gaussP) { +spectralsynth(double ** const aP, + unsigned int const n, + double const h, + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- Spectrally synthesized fractal motion in two dimensions. @@ -428,10 +391,9 @@ spectralsynth(double ** const aP, for (i = 0; i <= n / 2; i++) { for (j = 0; j <= n / 2; j++) { - phase = 2 * M_PI * ((pm_rand(&gaussP->randSt) & 0x7FFF) / - gaussP->arand); + phase = randPhase(randStP); if (i != 0 || j != 0) { - rad = pow((double) (i*i + j*j), -(h + 1) / 2) * gauss(gaussP); + rad = pow( (double) (i*i + j*j), - (h + 1) / 2) * pm_gaussrand(randStP); } else { rad = 0; } @@ -450,9 +412,8 @@ spectralsynth(double ** const aP, Imag(a, n / 2, n / 2) = 0; for (i = 1; i <= n / 2 - 1; i++) { for (j = 1; j <= n / 2 - 1; j++) { - phase = 2 * M_PI * ((pm_rand(&gaussP->randSt) & 0x7FFF) / - gaussP->arand); - rad = pow((double) (i * i + j * j), -(h + 1) / 2) * gauss(gaussP); + phase = randPhase(randStP); + rad = pow((double) (i * i + j * j), -(h + 1) / 2) * pm_gaussrand(randStP); rcos = rad * cos(phase); rsin = rad * sin(phase); Real(a, i, n - j) = rcos; @@ -507,11 +468,11 @@ temprgb(double const temp, static void etoile(pixel * const pix, - struct Gauss * const gaussP) { + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- Set a pixel in the starry sky. -----------------------------------------------------------------------------*/ - if ((pm_rand(&gaussP->randSt) % 1000) < starfraction) { + if ((pm_rand(randStP) % 1000) < starfraction) { double const starQuality = 0.5; /* Brightness distribution exponent */ double const starIntensity = 8; @@ -520,7 +481,7 @@ etoile(pixel * const pix, /* Tint distribution exponent */ double const v = MIN(255.0, - starIntensity * pow(1 / (1 - cast(0, 0.9999, gaussP)), + starIntensity * pow(1 / (1 - cast(0, 0.9999, randStP)), (double) starQuality)); /* We make a special case for star color of zero in order to @@ -538,8 +499,8 @@ etoile(pixel * const pix, double r, g, b; temp = 5500 + starcolor * - pow(1 / (1 - cast(0, 0.9999, gaussP)), starTintExp) * - ((pm_rand(&gaussP->randSt) & 7) ? -1 : 1); + pow(1 / (1 - cast(0, 0.9999, randStP)), starTintExp) * + ((pm_rand(randStP) & 7) ? -1 : 1); /* Constrain temperature to a reasonable value: >= 2600K (S Cephei/R Andromedae), <= 28,000 (Spica). */ @@ -606,18 +567,18 @@ makeCp(const double * const a, static void -createPlanetStuff(bool const clouds, - const double * const a, - unsigned int const n, - double ** const uP, - double ** const u1P, - unsigned int ** const bxfP, - unsigned int ** const bxcP, - unsigned char ** const cpP, - Vector * const sunvecP, - unsigned int const cols, - pixval const maxval, - struct Gauss * const gaussP) { +createPlanetStuff(bool const clouds, + const double * const a, + unsigned int const n, + double ** const uP, + double ** const u1P, + unsigned int ** const bxfP, + unsigned int ** const bxcP, + unsigned char ** const cpP, + Vector * const sunvecP, + unsigned int const cols, + pixval const maxval, + struct pm_randSt * const randStP) { double *u, *u1; unsigned int *bxf, *bxc; @@ -627,8 +588,8 @@ createPlanetStuff(bool const clouds, /* Compute incident light direction vector. */ - shang = hourspec ? hourangle : cast(0, 2 * M_PI, gaussP); - siang = inclspec ? inclangle : cast(-M_PI * 0.12, M_PI * 0.12, gaussP); + shang = hourspec ? hourangle : randPhase(randStP); + siang = inclspec ? inclangle : cast(-M_PI * 0.12, M_PI * 0.12, randStP); sunvecP->x = sin(shang) * cos(siang); sunvecP->y = sin(siang); @@ -636,7 +597,7 @@ createPlanetStuff(bool const clouds, /* Allow only 25% of random pictures to be crescents */ - if (!hourspec && ((pm_rand(&gaussP->randSt) % 100) < 75)) { + if (!hourspec && ((pm_rand(randStP) % 100) < 75)) { flipped = (sunvecP->z < 0); sunvecP->z = fabs(sunvecP->z); } else @@ -693,9 +654,9 @@ createPlanetStuff(bool const clouds, static void -generateStarrySkyRow(pixel * const pixels, - unsigned int const cols, - struct Gauss * const gaussP) { +generateStarrySkyRow(pixel * const pixels, + unsigned int const cols, + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- Generate a starry sky. Note that no FFT is performed; the output is generated directly from a power law @@ -704,7 +665,7 @@ generateStarrySkyRow(pixel * const pixels, unsigned int j; for (j = 0; j < cols; ++j) - etoile(pixels + j, gaussP); + etoile(pixels + j, randStP); } @@ -910,22 +871,22 @@ limbDarken(int * const irP, static void -generatePlanetRow(pixel * const pixelrow, - unsigned int const row, - unsigned int const rows, - unsigned int const cols, - double const t, - double const t1, - double * const u, - double * const u1, - unsigned char * const cp, - unsigned int * const bxc, - unsigned int * const bxf, - int const byc, - int const byf, - Vector const sunvec, - pixval const maxval, - struct Gauss * const gaussP) { +generatePlanetRow(pixel * const pixelrow, + unsigned int const row, + unsigned int const rows, + unsigned int const cols, + double const t, + double const t1, + double * const u, + double * const u1, + unsigned char * const cp, + unsigned int * const bxc, + unsigned int * const bxf, + int const byc, + int const byf, + Vector const sunvec, + pixval const maxval, + struct pm_randSt * const randStP) { unsigned int const StarClose = 2; @@ -968,25 +929,25 @@ generatePlanetRow(pixel * const pixelrow, /* Left stars */ for (col = 0; (int)col < (int)(cols/2 - (lcos + StarClose)); ++col) - etoile(&pixelrow[col], gaussP); + etoile(&pixelrow[col], randStP); /* Right stars */ for (col = cols/2 + (lcos + StarClose); col < cols; ++col) - etoile(&pixelrow[col], gaussP); + etoile(&pixelrow[col], randStP); } static void -genplanet(bool const stars, - bool const clouds, - const double * const a, - unsigned int const cols, - unsigned int const rows, - unsigned int const n, - unsigned int const rseed, - struct Gauss * const gaussP) { +genplanet(bool const stars, + bool const clouds, + const double * const a, + unsigned int const cols, + unsigned int const rows, + unsigned int const n, + unsigned int const rseed, + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- Generate planet from elevation array. @@ -1016,13 +977,13 @@ genplanet(bool const stars, clouds ? "clouds" : "planet", rseed, fracdim, powscale, meshsize); createPlanetStuff(clouds, a, n, &u, &u1, &bxf, &bxc, &cp, &sunvec, - cols, maxval, gaussP); + cols, maxval, randStP); } pixelrow = ppm_allocrow(cols); for (row = 0; row < rows; ++row) { if (stars) - generateStarrySkyRow(pixelrow, cols, gaussP); + generateStarrySkyRow(pixelrow, cols, randStP); else { double const by = (n - 1) * uprj(row, rows); int const byf = floor(by) * n; @@ -1039,7 +1000,7 @@ genplanet(bool const stars, t, t1, u, u1, cp, bxc, bxf, byc, byf, sunvec, maxval, - gaussP); + randStP); } ppm_writeppmrow(stdout, pixelrow, cols, maxval, FALSE); } @@ -1144,15 +1105,16 @@ planet(unsigned int const cols, -----------------------------------------------------------------------------*/ double * a; bool error; - struct Gauss gauss; + struct pm_randSt randSt; - initgauss(&gauss, rseed); + pm_randinit(&randSt); + pm_srand(&randSt, rseed); if (stars) { a = NULL; error = FALSE; } else { - spectralsynth(&a, meshsize, 3.0 - fracdim, &gauss); + spectralsynth(&a, meshsize, 3.0 - fracdim, &randSt); if (!a) { error = TRUE; } else { @@ -1164,7 +1126,7 @@ planet(unsigned int const cols, } } if (!error) - genplanet(stars, clouds, a, cols, rows, meshsize, rseed, &gauss); + genplanet(stars, clouds, a, cols, rows, meshsize, rseed, &randSt); if (a != NULL) free(a); @@ -1213,3 +1175,4 @@ main(int argc, const char ** argv) { } + |