[Change] Some needed cleanup in perlin noise stuff.

src/perlin.c

@@ -9,8 +9,6 @@
 
 #include "perlin.h"
 
-#define NEBULAE_Z                 32
-
 #define NOISE_MAX_OCTAVES         128
 #define NOISE_DEFAULT_HURST       0.5
 #define NOISE_DEFAULT_LACUNARITY  2.
@@ -30,15 +28,13 @@ typedef struct {
   float exponent[NOISE_MAX_OCTAVES];
 } perlin_data_t;
 
-static float* genNebulaeMap(const int w, const int h, const int n, float rug);
+static perlin_data_t* noise_new(float hurst, float lacunarity);
-SDL_Surface* surfaceFromNebulaeMap(float* map, const int w, const int h);
-static noise_t noise_new(float hurst, float lacunarity);
 /* Basic perlin noise. */
-static float noise_get(noise_t noise, float* f);
+static float noise_get(perlin_data_t* pdata, float* f);
 /* Fractional brownian motion. */
 /* Turbulence. */
-static float noise_turbulence(noise_t noise, float* f, float octaves);
+static float noise_turbulence(perlin_data_t* noise, float* f, float octaves);
-static void noise_delete(noise_t noise);
+static void noise_delete(perlin_data_t* noise);
 
 static float lattice(perlin_data_t* pdata, int ix, float fx, int iy,
     float fy, int iz, float fz) {
@@ -58,8 +54,6 @@ static float lattice(perlin_data_t* pdata, int ix, float fx, int iy,
   return value;
 }
 
-#define DEFAULT_SEED    0x15687436
-#define DELTA           1e-6f
 #define SWAP(a, b, t)   t = a; a = b; b = t
 
 #define FLOOR(a)        ((int) a - (a < 0 && a != (int)a))
@@ -74,7 +68,7 @@ static void normalize(float f[3]) {
   f[2] *= magnitude;
 }
 
-static noise_t noise_new(float hurst, float lacunarity) {
+static perlin_data_t* noise_new(float hurst, float lacunarity) {
   perlin_data_t* pdata = (perlin_data_t*)calloc(sizeof(perlin_data_t), 1);
   int i, j;
   unsigned char tmp;
@@ -102,8 +96,7 @@ static noise_t noise_new(float hurst, float lacunarity) {
   return (noise_t)pdata;
 }
 
-static float noise_get(noise_t noise, float *f ) {
+static float noise_get(perlin_data_t* pdata, float *f ) {
-  perlin_data_t* pdata = (perlin_data_t*)noise;
   int n[3];     /* Indexes to pass to lattice function. */
   float r[3];   /* Remainders to pass to lattice function. */
   float w[3];   /* Cubic values to pass to interpolation function. */
@@ -121,6 +114,10 @@ static float noise_get(noise_t noise, float *f ) {
   w[1] = CUBIC(r[1]);
   w[2] = CUBIC(r[2]);
 
+  /* 
+   * This is the big ugly part that is in dire need
+   * of optimisation!!!!
+   */
   value = LERP(LERP(LERP(lattice(pdata,n[0], r[0], n[1], r[1], n[2], r[2]),
           lattice(pdata,n[0]+1, r[0]-1, n[1], r[1], n[2], r[2]),
           w[0]),
@@ -140,7 +137,7 @@ static float noise_get(noise_t noise, float *f ) {
   return CLAMP(-0.99999f, 0.99999f, value);
 }
 
-static float noise_turbulence(noise_t noise, float* f, float octaves) {
+static float noise_turbulence(perlin_data_t* noise, float* f, float octaves) {
   float tf[3];
   perlin_data_t* pdata = (perlin_data_t*) noise;
   /* Init locals. */
@@ -152,38 +149,34 @@ static float noise_turbulence(noise_t noise, float* f, float octaves) {
   tf[2] = f[2];
 
   /* Inner loop of spectral construction, where the fractal is built. */
-  for(i = 0; i < (int)octaves; i++) {
+  for(i = 0; i < octaves; i++) {
     value += ABS(noise_get(noise, tf)) * pdata->exponent[i];
     tf[0] *= pdata->lacunarity;
     tf[1] *= pdata->lacunarity;
     tf[2] *= pdata->lacunarity;
   }
 
-  /* Take care of remainders in octaves. */
-  octaves -= (int)octaves;
-  if(octaves > DELTA)
-    value += octaves * ABS(noise_get(noise, tf)) * pdata->exponent[i];
   return CLAMP(-0.99999f, 0.99999f, value);
 }
 
-void noise_delete(noise_t noise) {
+void noise_delete(perlin_data_t* noise) {
   free((perlin_data_t*)noise);
 }
 
 /* Generate a 3d nebulae map of dimensions w,h,n with ruggedness rig. */
-static float* genNebulaeMap(const int w, const int h, const int n, float rug) {
+float* noise_genNebulaeMap(const int w, const int h, const int n, float rug) {
   int x, y, z;
   float f[3];
-  float octaves;
+  int octaves;
   float hurst;
   float lacunarity;
-  noise_t noise;
+  perlin_data_t* noise;
   float* nebulae;;
   float value;
   unsigned int* t, s;
 
   /* Pretty default values. */
-  octaves = 3.;
+  octaves = 3;
   hurst = NOISE_DEFAULT_HURST;
   lacunarity = NOISE_DEFAULT_LACUNARITY;
 
@@ -235,7 +228,7 @@ static float* genNebulaeMap(const int w, const int h, const int n, float rug) {
 }
 
 /* Generate an SDL_Surface from a 2d nebulae map. */
-SDL_Surface* surfaceFromNebulaeMap(float* map, const int w, const int h) {
+SDL_Surface* noise_surfaceFromNebulaeMap(float* map, const int w, const int h) {
   int i;
   SDL_Surface* sur;
   uint32_t* pix;
@@ -255,37 +248,13 @@ SDL_Surface* surfaceFromNebulaeMap(float* map, const int w, const int h) {
   return sur;
 }
 
-/* Generate nebulae and save them for late use. */
-void noise_generateNebulae(const int w, const int h) {
-  int i;
-  float* nebu;
-  SDL_Surface* sur;
-  char nebu_file[PATH_MAX];
-
-  /* Generate all the nebulae. */
-  nebu = genNebulaeMap(w, h, NEBULAE_Z, 15.);
-
-  /* Save each nebulae as an image. */
-  for(i = 0; i < NEBULAE_Z; i++) {
-    sur = surfaceFromNebulaeMap(&nebu[i*w*h], w, h);
-    snprintf(nebu_file, PATH_MAX, "%s/nebu_%02d.png", lfile_basePath(), i);
-    SDL_savePNG(sur, nebu_file);
-    SDL_FreeSurface(sur);
-  }
-
-  /* Cleanup. */
-  free(nebu);
-}
-
 glTexture* noise_genCloud(const int w, const int h, double rug) {
   float* map;
   SDL_Surface* sur;
   glTexture* tex;
 
-  /*noise_generateNebulae(w, h);*/
+  map = noise_genNebulaeMap(w, h, 1, rug);
-
+  sur = noise_surfaceFromNebulaeMap(map, w, h);
-  map = genNebulaeMap(w, h, 1, rug);
-  sur = surfaceFromNebulaeMap(map, w, h);
   free(map);
 
   tex = gl_loadImage(sur);

src/perlin.h

@@ -1,6 +1,9 @@
 #pragma once
 #include "opengl.h"
 
-void noise_generateNebulae(const int w, const int h);
+float* noise_genNebulaeMap(const int w, const int h, const int n, float rug);
+
+SDL_Surface* noise_surfaceFromNebulaeMap(float* map, const int w, const int h);
+
 glTexture* noise_genCloud(const int w, const int h, double rug);