diff options
Diffstat (limited to 'generator/pamcrater.c')
| -rw-r--r-- | generator/pamcrater.c | 61 |
1 files changed, 35 insertions, 26 deletions
diff --git a/generator/pamcrater.c b/generator/pamcrater.c index 43c27dbc..8f0e422d 100644 --- a/generator/pamcrater.c +++ b/generator/pamcrater.c @@ -48,6 +48,7 @@ #include "pm_c_util.h" #include "mallocvar.h" +#include "rand.h" #include "shhopt.h" #include "nstring.h" #include "pam.h" @@ -162,18 +163,18 @@ parseCommandLine(int argc, const char ** const argv, -static double const arand = 32767.0; /* Random number parameters */ static double const CdepthPower = 1.5; /* Crater depth power factor */ static double const DepthBias2 = 0.5; /* Square of depth bias */ static double const -cast(double const high) { +cast(double const high, + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- A random number in the range [0, 'high']. -----------------------------------------------------------------------------*/ - return high * ((rand() & 0x7FFF) / arand); + return high * ((double) pm_rand(randStP) / randStP->max); } @@ -220,7 +221,6 @@ terrainModP(struct pam * const pamP, - static sample terrainMod(struct pam * const pamP, tuple ** const terrain, @@ -252,11 +252,12 @@ setElev(struct pam * const pamP, static void -smallCrater(struct pam * const pamP, - tuple ** const terrain, - int const cx, - int const cy, - double const radius) { +smallCrater(struct pam * const pamP, + tuple ** const terrain, + int const cx, + int const cy, + double const radius, + struct pm_randSt * const randStP) { /*---------------------------------------------------------------------------- Generate a crater with a special method for tiny craters. @@ -283,10 +284,10 @@ smallCrater(struct pam * const pamP, /* The mean elevation of the Moore neighborhood (9 pixels centered on the crater location). */ - + /* Perturb the mean elevation by a small random factor. */ - int const x = radius >= 1 ? ((rand() >> 8) & 0x3) - 1 : 0; + int const x = radius >= 1 ? ((pm_rand(randStP) >> 8) & 0x3) - 1 : 0; assert(axelev > 0); @@ -374,7 +375,7 @@ normalCrater(struct pam * const pamP, av = (axelev + cz) * (1 - roll) + (terrainMod(pamP, terrain, x, y) + cz) * roll; av = MAX(1000, MIN(64000, av)); - + setElev(pamP, terrain, x, y, av); } } @@ -388,19 +389,20 @@ normalCrater(struct pam * const pamP, static void -plopCrater(struct pam * const pamP, - tuple ** const terrain, - int const cx, - int const cy, - double const radius, - bool const verbose) { +plopCrater(struct pam * const pamP, + tuple ** const terrain, + int const cx, + int const cy, + double const radius, + bool const verbose, + struct pm_randSt * const randStP) { if (verbose && pm_have_float_format()) pm_message("Plopping crater at (%4d, %4d) with radius %g", cx, cy, radius); if (radius < 3) - smallCrater (pamP, terrain, cx, cy, radius); + smallCrater (pamP, terrain, cx, cy, radius, randStP); else normalCrater(pamP, terrain, cx, cy, radius); } @@ -448,6 +450,7 @@ genCraters(struct CmdlineInfo const cmdline) { -----------------------------------------------------------------------------*/ tuple ** terrain; /* elevation array */ struct pam pam; + struct pm_randSt randSt; /* Allocate the elevation array and initialize it to mean surface elevation. @@ -455,18 +458,22 @@ genCraters(struct CmdlineInfo const cmdline) { initCanvas(cmdline.width, cmdline.height, &pam, &terrain); + pm_randinit(&randSt); + pm_srand2(&randSt, cmdline.randomseedSpec, cmdline.randomseed); + if (cmdline.test) plopCrater(&pam, terrain, pam.width/2 + cmdline.offset, pam.height/2 + cmdline.offset, - (double) cmdline.radius, cmdline.verbose); + (double) cmdline.radius, cmdline.verbose, + &randSt); else { unsigned int const ncraters = cmdline.number; /* num of craters */ unsigned int l; for (l = 0; l < ncraters; ++l) { - int const cx = cast((double) pam.width - 1); - int const cy = cast((double) pam.height - 1); + int const cx = cast((double) pam.width - 1, &randSt); + int const cy = cast((double) pam.height - 1, &randSt); /* Thanks, Rudy, for this equation that maps the uniformly distributed numbers from cast() into an area-law distribution @@ -475,9 +482,11 @@ genCraters(struct CmdlineInfo const cmdline) { Produces values within the interval: 0.56419 <= radius <= 56.419 */ - double const radius = sqrt(1 / (M_PI * (1 - cast(0.9999)))); + double const radius = + sqrt(1 / (M_PI * (1 - cast(0.9999, &randSt)))); - plopCrater(&pam, terrain, cx, cy, radius, cmdline.verbose); + plopCrater(&pam, terrain, cx, cy, radius, + cmdline.verbose, &randSt); if (((l + 1) % 100000) == 0) pm_message("%u craters generated of %u (%u%% done)", @@ -485,6 +494,8 @@ genCraters(struct CmdlineInfo const cmdline) { } } + pm_randterm(&randSt); + pnm_writepam(&pam, terrain); pnm_freepamarray(terrain, &pam); @@ -503,8 +514,6 @@ main(int argc, const char ** argv) { parseCommandLine(argc, argv, &cmdline); - srand(cmdline.randomseedSpec ? cmdline.randomseed : pm_randseed()); - genCraters(cmdline); return 0; |