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diff --git a/libs/rs/rsNoise.cpp b/libs/rs/rsNoise.cpp
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+/*
+ * This implementation of the noise functions was ported from the Java
+ * implementation by Jerry Huxtable (http://www.jhlabs.com) under
+ * Apache License 2.0 (see http://jhlabs.com/ip/filters/download.html)
+ *
+ * Original header:
+ *
+ * Copyright 2006 Jerry Huxtable
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "rsNoise.h"
+
+#include <math.h>
+#include <stdlib.h>
+#include <time.h>
+
+namespace android {
+namespace renderscript {
+
+#define B 0x100
+#define BM 0xff
+#define N 0x1000
+
+static int p[B + B + 2];
+static float g3[B + B + 2][3];
+static float g2[B + B + 2][2];
+static float g1[B + B + 2];
+static bool noise_start = true;
+
+#define lerpf(start, stop, amount) start + (stop - start) * amount
+
+static inline float noise_sCurve(float t)
+{
+ return t * t * (3.0f - 2.0f * t);
+}
+
+inline void SC_normalizef2(float v[])
+{
+ float s = (float)sqrtf(v[0] * v[0] + v[1] * v[1]);
+ v[0] = v[0] / s;
+ v[1] = v[1] / s;
+}
+
+inline void SC_normalizef3(float v[])
+{
+ float s = (float)sqrtf(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
+ v[0] = v[0] / s;
+ v[1] = v[1] / s;
+ v[2] = v[2] / s;
+}
+
+static void noise_init()
+{
+ int i, j, k;
+
+ for (i = 0; i < B; i++) {
+ p[i] = i;
+
+ g1[i] = (float)((rand() % (B + B)) - B) / B;
+
+ for (j = 0; j < 2; j++)
+ g2[i][j] = (float)((rand() % (B + B)) - B) / B;
+ SC_normalizef2(g2[i]);
+
+ for (j = 0; j < 3; j++)
+ g3[i][j] = (float)((rand() % (B + B)) - B) / B;
+ SC_normalizef3(g3[i]);
+ }
+
+ for (i = B-1; i >= 0; i--) {
+ k = p[i];
+ p[i] = p[j = rand() % B];
+ p[j] = k;
+ }
+
+ for (i = 0; i < B + 2; i++) {
+ p[B + i] = p[i];
+ g1[B + i] = g1[i];
+ for (j = 0; j < 2; j++)
+ g2[B + i][j] = g2[i][j];
+ for (j = 0; j < 3; j++)
+ g3[B + i][j] = g3[i][j];
+ }
+}
+
+float SC_noisef(float x)
+{
+ srand(time(NULL));
+ int bx0, bx1;
+ float rx0, rx1, sx, t, u, v;
+
+ if (noise_start) {
+ noise_start = false;
+ noise_init();
+ }
+
+ t = x + N;
+ bx0 = ((int)t) & BM;
+ bx1 = (bx0+1) & BM;
+ rx0 = t - (int)t;
+ rx1 = rx0 - 1.0f;
+
+ sx = noise_sCurve(rx0);
+
+ u = rx0 * g1[p[bx0]];
+ v = rx1 * g1[p[bx1]];
+ return 2.3f * lerpf(u, v, sx);
+}
+
+float SC_noisef2(float x, float y)
+{
+ srand(time(NULL));
+ int bx0, bx1, by0, by1, b00, b10, b01, b11;
+ float rx0, rx1, ry0, ry1, sx, sy, a, b, t, u, v;
+ float *q;
+ int i, j;
+
+ if (noise_start) {
+ noise_start = false;
+ noise_init();
+ }
+
+ t = x + N;
+ bx0 = ((int)t) & BM;
+ bx1 = (bx0+1) & BM;
+ rx0 = t - (int)t;
+ rx1 = rx0 - 1.0f;
+
+ t = y + N;
+ by0 = ((int)t) & BM;
+ by1 = (by0+1) & BM;
+ ry0 = t - (int)t;
+ ry1 = ry0 - 1.0f;
+
+ i = p[bx0];
+ j = p[bx1];
+
+ b00 = p[i + by0];
+ b10 = p[j + by0];
+ b01 = p[i + by1];
+ b11 = p[j + by1];
+
+ sx = noise_sCurve(rx0);
+ sy = noise_sCurve(ry0);
+
+ q = g2[b00]; u = rx0 * q[0] + ry0 * q[1];
+ q = g2[b10]; v = rx1 * q[0] + ry0 * q[1];
+ a = lerpf(u, v, sx);
+
+ q = g2[b01]; u = rx0 * q[0] + ry1 * q[1];
+ q = g2[b11]; v = rx1 * q[0] + ry1 * q[1];
+ b = lerpf(u, v, sx);
+
+ return 1.5f*lerpf(a, b, sy);
+}
+
+float SC_noisef3(float x, float y, float z)
+{
+ srand(time(NULL));
+ int bx0, bx1, by0, by1, bz0, bz1, b00, b10, b01, b11;
+ float rx0, rx1, ry0, ry1, rz0, rz1, sy, sz, a, b, c, d, t, u, v;
+ float *q;
+ int i, j;
+
+ if (noise_start) {
+ noise_start = false;
+ noise_init();
+ }
+
+ t = x + N;
+ bx0 = ((int)t) & BM;
+ bx1 = (bx0+1) & BM;
+ rx0 = t - (int)t;
+ rx1 = rx0 - 1.0f;
+
+ t = y + N;
+ by0 = ((int)t) & BM;
+ by1 = (by0+1) & BM;
+ ry0 = t - (int)t;
+ ry1 = ry0 - 1.0f;
+
+ t = z + N;
+ bz0 = ((int)t) & BM;
+ bz1 = (bz0+1) & BM;
+ rz0 = t - (int)t;
+ rz1 = rz0 - 1.0f;
+
+ i = p[bx0];
+ j = p[bx1];
+
+ b00 = p[i + by0];
+ b10 = p[j + by0];
+ b01 = p[i + by1];
+ b11 = p[j + by1];
+
+ t = noise_sCurve(rx0);
+ sy = noise_sCurve(ry0);
+ sz = noise_sCurve(rz0);
+
+ q = g3[b00 + bz0]; u = rx0 * q[0] + ry0 * q[1] + rz0 * q[2];
+ q = g3[b10 + bz0]; v = rx1 * q[0] + ry0 * q[1] + rz0 * q[2];
+ a = lerpf(u, v, t);
+
+ q = g3[b01 + bz0]; u = rx0 * q[0] + ry1 * q[1] + rz0 * q[2];
+ q = g3[b11 + bz0]; v = rx1 * q[0] + ry1 * q[1] + rz0 * q[2];
+ b = lerpf(u, v, t);
+
+ c = lerpf(a, b, sy);
+
+ q = g3[b00 + bz1]; u = rx0 * q[0] + ry0 * q[1] + rz1 * q[2];
+ q = g3[b10 + bz1]; v = rx1 * q[0] + ry0 * q[1] + rz1 * q[2];
+ a = lerpf(u, v, t);
+
+ q = g3[b01 + bz1]; u = rx0 * q[0] + ry1 * q[1] + rz1 * q[2];
+ q = g3[b11 + bz1]; v = rx1 * q[0] + ry1 * q[1] + rz1 * q[2];
+ b = lerpf(u, v, t);
+
+ d = lerpf(a, b, sy);
+
+ return 1.5f*lerpf(c, d, sz);
+}
+
+float SC_turbulencef2(float x, float y, float octaves)
+{
+ srand(time(NULL));
+ float t = 0.0f;
+
+ for (float f = 1.0f; f <= octaves; f *= 2)
+ t += fabs(SC_noisef2(f * x, f * y)) / f;
+ return t;
+}
+
+float SC_turbulencef3(float x, float y, float z, float octaves)
+{
+ srand(time(NULL));
+ float t = 0.0f;
+
+ for (float f = 1.0f; f <= octaves; f *= 2)
+ t += fabs(SC_noisef3(f * x, f * y, f * z)) / f;
+ return t;
+}
+
+}
+} \ No newline at end of file
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