yet another API cleanup

gen.c

@@ -1,64 +1,14 @@
 #include "cubes.h"
-#include <math.h>
+#include "noise.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 struct chunk *chunks = NULL;
 int lastI = 0;
-int seed = 69420;
 int prevExists = 0;
-double interpolate(double a0, double a1, double w) {
-  return (a1 - a0) * (3.0 - w * 2.0) * w * w + a0;
-}
 
-int hash_combine(int a, int b) { return b + 0x9e3779b9 + (a << 6) + (a >> 2); }
-
-struct v2f perlin_grad(int x, int y) {
-  int x_hash = hash_combine(x, seed);
-  int y_hash = hash_combine(seed, y);
-
-  double random = hash_combine(x_hash, y_hash) * (M_PI / ~(~0u >> 1));
-  struct v2f out = {cos(random), sin(random)};
-  return out;
-}
-
-double perlin_dot(double ix, double iy, double x, double y) {
-  struct v2f grad = perlin_grad(ix, iy);
-
-  double dx = x - (double)ix;
-  double dy = y - (double)iy;
-  return (dx * grad.pos[0] + dy * grad.pos[1]);
-}
-
-double perlin_calc(double x, double y, double s) {
-  x /= s;
-  y /= s;
-
-  int x0 = (int)floor(x);
-  int x1 = x0 + 1;
-  int y0 = (int)floor(y);
-  int y1 = y0 + 1;
-
-  float sx = x - (float)x0;
-  float sy = y - (float)y0;
-
-  float n0, n1, ix0, ix1, value;
-
-  n0 = perlin_dot(x0, y0, x, y);
-  n1 = perlin_dot(x1, y0, x, y);
-  ix0 = interpolate(n0, n1, sx);
-
-  n0 = perlin_dot(x0, y1, x, y);
-  n1 = perlin_dot(x1, y1, x, y);
-  ix1 = interpolate(n0, n1, sx);
-
-  value = interpolate(ix0, ix1, sy);
-
-  return value;
-}
-
-struct chunk fetch_chunk(int x, int y, int z, int ci, int h) {
+struct chunk gen_chunk(int x, int y, int z, int ci, int h) {
 
   struct chunk *chunks2 = chunks; // &chunks[CBUF_ALL * ci];
 
@@ -128,22 +78,7 @@ struct chunk fetch_chunk(int x, int y, int z, int ci, int h) {
 
   int c = 0;
 
-  for (int x2 = 0; x2 < CHUNK_LENGTH; x2++) {
-    int x3 = x2 + x * CHUNK_LENGTH;
-    for (int z2 = 0; z2 < CHUNK_LENGTH; z2++) {
-      int z3 = z2 + z * CHUNK_LENGTH;
-      double hp = perlin_calc(x3, z3, 128.0);
-      hp = ((hp > 0.0) ? -1.0 : 1.0) * (pow(fabs(hp), 0.7));
-      hp *= 32.0;
-      int h = hp + 32;
-
-      for (int y2 = 0; y2 < CHUNK_LENGTH; y2++) {
-        int y3 = y2 + y * CHUNK_LENGTH;
-        chunk.blocks[c] = (y3 < h) ? (((int)((hp + 64.0) * 2.98) % 3) + 1) : 0;
-        c++;
-      }
-    }
-  }
+  chunk = noise_chunk(chunk, x, y, z);
 
   chunks2[i] = chunk;
 
@@ -157,21 +92,21 @@ struct chunk fetch_chunk(int x, int y, int z, int ci, int h) {
   return chunk;
 }
 
-void purge_chunks(int ci) {
+void gen_init() {
   if (chunks == NULL) {
     chunks = calloc(CHUNK_ALL, sizeof(struct chunk));
   }
 }
 
-void free_chunks() { free(chunks); }
+void gen_free() { free(chunks); }
 
-int cube_exists(int x, int y, int z, struct chunk dat, int ci) {
+int gen_cube(int x, int y, int z, struct chunk dat, int ci) {
   if (x < 0 || y < 0 || z < 0)
     return 0;
 
   if (dat.exists == 0 || dat.x != (x / CHUNK_LENGTH) ||
       dat.y != (y / CHUNK_LENGTH) || dat.z != (z / CHUNK_LENGTH)) {
-    dat = fetch_chunk((x / CHUNK_LENGTH), (y / CHUNK_LENGTH),
+    dat = gen_chunk((x / CHUNK_LENGTH), (y / CHUNK_LENGTH),
                       (z / CHUNK_LENGTH), ci, dat.exists);
     prevExists = dat.exists;
   }