mirror of
https://github.com/moparisthebest/minetest
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809 lines
19 KiB
C++
809 lines
19 KiB
C++
/*
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* Minetest
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* Copyright (C) 2010-2014 celeron55, Perttu Ahola <celeron55@gmail.com>
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* Copyright (C) 2010-2014 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification, are
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* permitted provided that the following conditions are met:
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* 1. Redistributions of source code must retain the above copyright notice, this list of
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* conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright notice, this list
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* of conditions and the following disclaimer in the documentation and/or other materials
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* provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR
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* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <math.h>
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#include "noise.h"
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#include <iostream>
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#include <string.h> // memset
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#include "debug.h"
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#include "util/numeric.h"
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#include "util/string.h"
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#include "exceptions.h"
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#define NOISE_MAGIC_X 1619
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#define NOISE_MAGIC_Y 31337
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#define NOISE_MAGIC_Z 52591
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#define NOISE_MAGIC_SEED 1013
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typedef float (*Interp2dFxn)(
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float v00, float v10, float v01, float v11,
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float x, float y);
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typedef float (*Interp3dFxn)(
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float v000, float v100, float v010, float v110,
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float v001, float v101, float v011, float v111,
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float x, float y, float z);
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float cos_lookup[16] = {
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1.0, 0.9238, 0.7071, 0.3826, 0, -0.3826, -0.7071, -0.9238,
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1.0, -0.9238, -0.7071, -0.3826, 0, 0.3826, 0.7071, 0.9238
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};
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FlagDesc flagdesc_noiseparams[] = {
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{"defaults", NOISE_FLAG_DEFAULTS},
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{"eased", NOISE_FLAG_EASED},
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{"absvalue", NOISE_FLAG_ABSVALUE},
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{"pointbuffer", NOISE_FLAG_POINTBUFFER},
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{"simplex", NOISE_FLAG_SIMPLEX},
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{NULL, 0}
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};
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///////////////////////////////////////////////////////////////////////////////
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PcgRandom::PcgRandom(u64 state, u64 seq)
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{
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seed(state, seq);
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}
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void PcgRandom::seed(u64 state, u64 seq)
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{
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m_state = 0U;
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m_inc = (seq << 1u) | 1u;
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next();
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m_state += state;
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next();
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}
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u32 PcgRandom::next()
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{
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u64 oldstate = m_state;
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m_state = oldstate * 6364136223846793005ULL + m_inc;
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u32 xorshifted = ((oldstate >> 18u) ^ oldstate) >> 27u;
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u32 rot = oldstate >> 59u;
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return (xorshifted >> rot) | (xorshifted << ((-rot) & 31));
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}
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u32 PcgRandom::range(u32 bound)
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{
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// If the bound is 0, we cover the whole RNG's range
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if (bound == 0)
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return next();
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/*
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This is an optimization of the expression:
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0x100000000ull % bound
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since 64-bit modulo operations typically much slower than 32.
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*/
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u32 threshold = -bound % bound;
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u32 r;
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/*
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If the bound is not a multiple of the RNG's range, it may cause bias,
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e.g. a RNG has a range from 0 to 3 and we take want a number 0 to 2.
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Using rand() % 3, the number 0 would be twice as likely to appear.
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With a very large RNG range, the effect becomes less prevalent but
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still present.
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This can be solved by modifying the range of the RNG to become a
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multiple of bound by dropping values above the a threshold.
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In our example, threshold == 4 % 3 == 1, so reject values < 1
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(that is, 0), thus making the range == 3 with no bias.
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This loop may look dangerous, but will always terminate due to the
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RNG's property of uniformity.
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*/
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while ((r = next()) < threshold)
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;
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return r % bound;
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}
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s32 PcgRandom::range(s32 min, s32 max)
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{
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if (max < min)
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throw PrngException("Invalid range (max < min)");
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u32 bound = max - min + 1;
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return range(bound) + min;
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}
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void PcgRandom::bytes(void *out, size_t len)
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{
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u8 *outb = (u8 *)out;
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int bytes_left = 0;
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u32 r;
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while (len--) {
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if (bytes_left == 0) {
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bytes_left = sizeof(u32);
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r = next();
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}
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*outb = r & 0xFF;
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outb++;
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bytes_left--;
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r >>= CHAR_BIT;
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}
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}
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s32 PcgRandom::randNormalDist(s32 min, s32 max, int num_trials)
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{
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s32 accum = 0;
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for (int i = 0; i != num_trials; i++)
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accum += range(min, max);
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return myround((float)accum / num_trials);
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}
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///////////////////////////////////////////////////////////////////////////////
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float noise2d(int x, int y, s32 seed)
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{
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unsigned int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y
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+ NOISE_MAGIC_SEED * seed) & 0x7fffffff;
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n = (n >> 13) ^ n;
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n = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff;
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return 1.f - (float)(int)n / 0x40000000;
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}
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float noise3d(int x, int y, int z, s32 seed)
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{
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unsigned int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y + NOISE_MAGIC_Z * z
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+ NOISE_MAGIC_SEED * seed) & 0x7fffffff;
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n = (n >> 13) ^ n;
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n = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff;
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return 1.f - (float)(int)n / 0x40000000;
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}
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inline float dotProduct(float vx, float vy, float wx, float wy)
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{
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return vx * wx + vy * wy;
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}
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inline float linearInterpolation(float v0, float v1, float t)
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{
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return v0 + (v1 - v0) * t;
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}
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inline float biLinearInterpolation(
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float v00, float v10,
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float v01, float v11,
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float x, float y)
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{
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float tx = easeCurve(x);
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float ty = easeCurve(y);
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float u = linearInterpolation(v00, v10, tx);
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float v = linearInterpolation(v01, v11, tx);
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return linearInterpolation(u, v, ty);
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}
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inline float biLinearInterpolationNoEase(
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float v00, float v10,
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float v01, float v11,
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float x, float y)
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{
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float u = linearInterpolation(v00, v10, x);
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float v = linearInterpolation(v01, v11, x);
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return linearInterpolation(u, v, y);
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}
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float triLinearInterpolation(
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float v000, float v100, float v010, float v110,
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float v001, float v101, float v011, float v111,
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float x, float y, float z)
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{
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float tx = easeCurve(x);
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float ty = easeCurve(y);
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float tz = easeCurve(z);
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float u = biLinearInterpolationNoEase(v000, v100, v010, v110, tx, ty);
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float v = biLinearInterpolationNoEase(v001, v101, v011, v111, tx, ty);
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return linearInterpolation(u, v, tz);
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}
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float triLinearInterpolationNoEase(
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float v000, float v100, float v010, float v110,
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float v001, float v101, float v011, float v111,
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float x, float y, float z)
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{
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float u = biLinearInterpolationNoEase(v000, v100, v010, v110, x, y);
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float v = biLinearInterpolationNoEase(v001, v101, v011, v111, x, y);
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return linearInterpolation(u, v, z);
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}
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float noise2d_gradient(float x, float y, s32 seed, bool eased)
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{
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// Calculate the integer coordinates
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int x0 = myfloor(x);
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int y0 = myfloor(y);
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// Calculate the remaining part of the coordinates
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float xl = x - (float)x0;
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float yl = y - (float)y0;
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// Get values for corners of square
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float v00 = noise2d(x0, y0, seed);
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float v10 = noise2d(x0+1, y0, seed);
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float v01 = noise2d(x0, y0+1, seed);
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float v11 = noise2d(x0+1, y0+1, seed);
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// Interpolate
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if (eased)
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return biLinearInterpolation(v00, v10, v01, v11, xl, yl);
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else
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return biLinearInterpolationNoEase(v00, v10, v01, v11, xl, yl);
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}
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float noise3d_gradient(float x, float y, float z, s32 seed, bool eased)
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{
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// Calculate the integer coordinates
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int x0 = myfloor(x);
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int y0 = myfloor(y);
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int z0 = myfloor(z);
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// Calculate the remaining part of the coordinates
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float xl = x - (float)x0;
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float yl = y - (float)y0;
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float zl = z - (float)z0;
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// Get values for corners of cube
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float v000 = noise3d(x0, y0, z0, seed);
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float v100 = noise3d(x0 + 1, y0, z0, seed);
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float v010 = noise3d(x0, y0 + 1, z0, seed);
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float v110 = noise3d(x0 + 1, y0 + 1, z0, seed);
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float v001 = noise3d(x0, y0, z0 + 1, seed);
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float v101 = noise3d(x0 + 1, y0, z0 + 1, seed);
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float v011 = noise3d(x0, y0 + 1, z0 + 1, seed);
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float v111 = noise3d(x0 + 1, y0 + 1, z0 + 1, seed);
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// Interpolate
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if (eased) {
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return triLinearInterpolation(
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v000, v100, v010, v110,
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v001, v101, v011, v111,
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xl, yl, zl);
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} else {
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return triLinearInterpolationNoEase(
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v000, v100, v010, v110,
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v001, v101, v011, v111,
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xl, yl, zl);
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}
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}
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float noise2d_perlin(float x, float y, s32 seed,
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int octaves, float persistence, bool eased)
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{
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float a = 0;
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float f = 1.0;
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float g = 1.0;
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for (int i = 0; i < octaves; i++)
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{
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a += g * noise2d_gradient(x * f, y * f, seed + i, eased);
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f *= 2.0;
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g *= persistence;
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}
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return a;
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}
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float noise2d_perlin_abs(float x, float y, s32 seed,
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int octaves, float persistence, bool eased)
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{
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float a = 0;
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float f = 1.0;
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float g = 1.0;
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for (int i = 0; i < octaves; i++) {
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a += g * fabs(noise2d_gradient(x * f, y * f, seed + i, eased));
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f *= 2.0;
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g *= persistence;
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}
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return a;
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}
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float noise3d_perlin(float x, float y, float z, s32 seed,
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int octaves, float persistence, bool eased)
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{
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float a = 0;
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float f = 1.0;
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float g = 1.0;
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for (int i = 0; i < octaves; i++) {
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a += g * noise3d_gradient(x * f, y * f, z * f, seed + i, eased);
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f *= 2.0;
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g *= persistence;
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}
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return a;
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}
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float noise3d_perlin_abs(float x, float y, float z, s32 seed,
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int octaves, float persistence, bool eased)
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{
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float a = 0;
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float f = 1.0;
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float g = 1.0;
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for (int i = 0; i < octaves; i++) {
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a += g * fabs(noise3d_gradient(x * f, y * f, z * f, seed + i, eased));
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f *= 2.0;
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g *= persistence;
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}
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return a;
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}
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float contour(float v)
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{
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v = fabs(v);
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if (v >= 1.0)
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return 0.0;
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return (1.0 - v);
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}
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///////////////////////// [ New noise ] ////////////////////////////
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float NoisePerlin2D(NoiseParams *np, float x, float y, s32 seed)
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{
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float a = 0;
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float f = 1.0;
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float g = 1.0;
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x /= np->spread.X;
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y /= np->spread.Y;
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seed += np->seed;
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for (size_t i = 0; i < np->octaves; i++) {
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float noiseval = noise2d_gradient(x * f, y * f, seed + i,
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np->flags & (NOISE_FLAG_DEFAULTS | NOISE_FLAG_EASED));
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if (np->flags & NOISE_FLAG_ABSVALUE)
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noiseval = fabs(noiseval);
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a += g * noiseval;
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f *= np->lacunarity;
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g *= np->persist;
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}
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return np->offset + a * np->scale;
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}
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float NoisePerlin3D(NoiseParams *np, float x, float y, float z, s32 seed)
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{
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float a = 0;
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float f = 1.0;
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float g = 1.0;
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x /= np->spread.X;
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y /= np->spread.Y;
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z /= np->spread.Z;
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seed += np->seed;
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for (size_t i = 0; i < np->octaves; i++) {
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float noiseval = noise3d_gradient(x * f, y * f, z * f, seed + i,
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np->flags & NOISE_FLAG_EASED);
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if (np->flags & NOISE_FLAG_ABSVALUE)
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noiseval = fabs(noiseval);
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a += g * noiseval;
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f *= np->lacunarity;
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g *= np->persist;
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}
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return np->offset + a * np->scale;
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}
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Noise::Noise(NoiseParams *np_, s32 seed, u32 sx, u32 sy, u32 sz)
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{
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memcpy(&np, np_, sizeof(np));
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this->seed = seed;
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this->sx = sx;
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this->sy = sy;
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this->sz = sz;
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this->persist_buf = NULL;
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this->gradient_buf = NULL;
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this->result = NULL;
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allocBuffers();
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}
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Noise::~Noise()
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{
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delete[] gradient_buf;
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delete[] persist_buf;
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delete[] noise_buf;
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delete[] result;
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}
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void Noise::allocBuffers()
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{
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if (sx < 1)
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sx = 1;
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if (sy < 1)
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sy = 1;
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if (sz < 1)
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sz = 1;
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this->noise_buf = NULL;
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resizeNoiseBuf(sz > 1);
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delete[] gradient_buf;
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delete[] persist_buf;
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delete[] result;
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try {
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size_t bufsize = sx * sy * sz;
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this->persist_buf = NULL;
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this->gradient_buf = new float[bufsize];
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this->result = new float[bufsize];
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} catch (std::bad_alloc &e) {
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throw InvalidNoiseParamsException();
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}
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}
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void Noise::setSize(u32 sx, u32 sy, u32 sz)
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{
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this->sx = sx;
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this->sy = sy;
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this->sz = sz;
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allocBuffers();
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}
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void Noise::setSpreadFactor(v3f spread)
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{
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this->np.spread = spread;
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resizeNoiseBuf(sz > 1);
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}
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void Noise::setOctaves(int octaves)
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{
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this->np.octaves = octaves;
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resizeNoiseBuf(sz > 1);
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}
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void Noise::resizeNoiseBuf(bool is3d)
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{
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//maximum possible spread value factor
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float ofactor = (np.lacunarity > 1.0) ?
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pow(np.lacunarity, np.octaves - 1) :
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np.lacunarity;
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// noise lattice point count
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// (int)(sz * spread * ofactor) is # of lattice points crossed due to length
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float num_noise_points_x = sx * ofactor / np.spread.X;
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float num_noise_points_y = sy * ofactor / np.spread.Y;
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float num_noise_points_z = sz * ofactor / np.spread.Z;
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// protect against obviously invalid parameters
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if (num_noise_points_x > 1000000000.f ||
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num_noise_points_y > 1000000000.f ||
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num_noise_points_z > 1000000000.f)
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throw InvalidNoiseParamsException();
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// + 2 for the two initial endpoints
|
|
// + 1 for potentially crossing a boundary due to offset
|
|
size_t nlx = (size_t)ceil(num_noise_points_x) + 3;
|
|
size_t nly = (size_t)ceil(num_noise_points_y) + 3;
|
|
size_t nlz = is3d ? (size_t)ceil(num_noise_points_z) + 3 : 1;
|
|
|
|
delete[] noise_buf;
|
|
try {
|
|
noise_buf = new float[nlx * nly * nlz];
|
|
} catch (std::bad_alloc &e) {
|
|
throw InvalidNoiseParamsException();
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* NB: This algorithm is not optimal in terms of space complexity. The entire
|
|
* integer lattice of noise points could be done as 2 lines instead, and for 3D,
|
|
* 2 lines + 2 planes.
|
|
* However, this would require the noise calls to be interposed with the
|
|
* interpolation loops, which may trash the icache, leading to lower overall
|
|
* performance.
|
|
* Another optimization that could save half as many noise calls is to carry over
|
|
* values from the previous noise lattice as midpoints in the new lattice for the
|
|
* next octave.
|
|
*/
|
|
#define idx(x, y) ((y) * nlx + (x))
|
|
void Noise::gradientMap2D(
|
|
float x, float y,
|
|
float step_x, float step_y,
|
|
s32 seed)
|
|
{
|
|
float v00, v01, v10, v11, u, v, orig_u;
|
|
u32 index, i, j, noisex, noisey;
|
|
u32 nlx, nly;
|
|
s32 x0, y0;
|
|
|
|
bool eased = np.flags & (NOISE_FLAG_DEFAULTS | NOISE_FLAG_EASED);
|
|
Interp2dFxn interpolate = eased ?
|
|
biLinearInterpolation : biLinearInterpolationNoEase;
|
|
|
|
x0 = floor(x);
|
|
y0 = floor(y);
|
|
u = x - (float)x0;
|
|
v = y - (float)y0;
|
|
orig_u = u;
|
|
|
|
//calculate noise point lattice
|
|
nlx = (u32)(u + sx * step_x) + 2;
|
|
nly = (u32)(v + sy * step_y) + 2;
|
|
index = 0;
|
|
for (j = 0; j != nly; j++)
|
|
for (i = 0; i != nlx; i++)
|
|
noise_buf[index++] = noise2d(x0 + i, y0 + j, seed);
|
|
|
|
//calculate interpolations
|
|
index = 0;
|
|
noisey = 0;
|
|
for (j = 0; j != sy; j++) {
|
|
v00 = noise_buf[idx(0, noisey)];
|
|
v10 = noise_buf[idx(1, noisey)];
|
|
v01 = noise_buf[idx(0, noisey + 1)];
|
|
v11 = noise_buf[idx(1, noisey + 1)];
|
|
|
|
u = orig_u;
|
|
noisex = 0;
|
|
for (i = 0; i != sx; i++) {
|
|
gradient_buf[index++] = interpolate(v00, v10, v01, v11, u, v);
|
|
|
|
u += step_x;
|
|
if (u >= 1.0) {
|
|
u -= 1.0;
|
|
noisex++;
|
|
v00 = v10;
|
|
v01 = v11;
|
|
v10 = noise_buf[idx(noisex + 1, noisey)];
|
|
v11 = noise_buf[idx(noisex + 1, noisey + 1)];
|
|
}
|
|
}
|
|
|
|
v += step_y;
|
|
if (v >= 1.0) {
|
|
v -= 1.0;
|
|
noisey++;
|
|
}
|
|
}
|
|
}
|
|
#undef idx
|
|
|
|
|
|
#define idx(x, y, z) ((z) * nly * nlx + (y) * nlx + (x))
|
|
void Noise::gradientMap3D(
|
|
float x, float y, float z,
|
|
float step_x, float step_y, float step_z,
|
|
s32 seed)
|
|
{
|
|
float v000, v010, v100, v110;
|
|
float v001, v011, v101, v111;
|
|
float u, v, w, orig_u, orig_v;
|
|
u32 index, i, j, k, noisex, noisey, noisez;
|
|
u32 nlx, nly, nlz;
|
|
s32 x0, y0, z0;
|
|
|
|
Interp3dFxn interpolate = (np.flags & NOISE_FLAG_EASED) ?
|
|
triLinearInterpolation : triLinearInterpolationNoEase;
|
|
|
|
x0 = floor(x);
|
|
y0 = floor(y);
|
|
z0 = floor(z);
|
|
u = x - (float)x0;
|
|
v = y - (float)y0;
|
|
w = z - (float)z0;
|
|
orig_u = u;
|
|
orig_v = v;
|
|
|
|
//calculate noise point lattice
|
|
nlx = (u32)(u + sx * step_x) + 2;
|
|
nly = (u32)(v + sy * step_y) + 2;
|
|
nlz = (u32)(w + sz * step_z) + 2;
|
|
index = 0;
|
|
for (k = 0; k != nlz; k++)
|
|
for (j = 0; j != nly; j++)
|
|
for (i = 0; i != nlx; i++)
|
|
noise_buf[index++] = noise3d(x0 + i, y0 + j, z0 + k, seed);
|
|
|
|
//calculate interpolations
|
|
index = 0;
|
|
noisey = 0;
|
|
noisez = 0;
|
|
for (k = 0; k != sz; k++) {
|
|
v = orig_v;
|
|
noisey = 0;
|
|
for (j = 0; j != sy; j++) {
|
|
v000 = noise_buf[idx(0, noisey, noisez)];
|
|
v100 = noise_buf[idx(1, noisey, noisez)];
|
|
v010 = noise_buf[idx(0, noisey + 1, noisez)];
|
|
v110 = noise_buf[idx(1, noisey + 1, noisez)];
|
|
v001 = noise_buf[idx(0, noisey, noisez + 1)];
|
|
v101 = noise_buf[idx(1, noisey, noisez + 1)];
|
|
v011 = noise_buf[idx(0, noisey + 1, noisez + 1)];
|
|
v111 = noise_buf[idx(1, noisey + 1, noisez + 1)];
|
|
|
|
u = orig_u;
|
|
noisex = 0;
|
|
for (i = 0; i != sx; i++) {
|
|
gradient_buf[index++] = interpolate(
|
|
v000, v100, v010, v110,
|
|
v001, v101, v011, v111,
|
|
u, v, w);
|
|
|
|
u += step_x;
|
|
if (u >= 1.0) {
|
|
u -= 1.0;
|
|
noisex++;
|
|
v000 = v100;
|
|
v010 = v110;
|
|
v100 = noise_buf[idx(noisex + 1, noisey, noisez)];
|
|
v110 = noise_buf[idx(noisex + 1, noisey + 1, noisez)];
|
|
v001 = v101;
|
|
v011 = v111;
|
|
v101 = noise_buf[idx(noisex + 1, noisey, noisez + 1)];
|
|
v111 = noise_buf[idx(noisex + 1, noisey + 1, noisez + 1)];
|
|
}
|
|
}
|
|
|
|
v += step_y;
|
|
if (v >= 1.0) {
|
|
v -= 1.0;
|
|
noisey++;
|
|
}
|
|
}
|
|
|
|
w += step_z;
|
|
if (w >= 1.0) {
|
|
w -= 1.0;
|
|
noisez++;
|
|
}
|
|
}
|
|
}
|
|
#undef idx
|
|
|
|
|
|
float *Noise::perlinMap2D(float x, float y, float *persistence_map)
|
|
{
|
|
float f = 1.0, g = 1.0;
|
|
size_t bufsize = sx * sy;
|
|
|
|
x /= np.spread.X;
|
|
y /= np.spread.Y;
|
|
|
|
memset(result, 0, sizeof(float) * bufsize);
|
|
|
|
if (persistence_map) {
|
|
if (!persist_buf)
|
|
persist_buf = new float[bufsize];
|
|
for (size_t i = 0; i != bufsize; i++)
|
|
persist_buf[i] = 1.0;
|
|
}
|
|
|
|
for (size_t oct = 0; oct < np.octaves; oct++) {
|
|
gradientMap2D(x * f, y * f,
|
|
f / np.spread.X, f / np.spread.Y,
|
|
seed + np.seed + oct);
|
|
|
|
updateResults(g, persist_buf, persistence_map, bufsize);
|
|
|
|
f *= np.lacunarity;
|
|
g *= np.persist;
|
|
}
|
|
|
|
if (fabs(np.offset - 0.f) > 0.00001 || fabs(np.scale - 1.f) > 0.00001) {
|
|
for (size_t i = 0; i != bufsize; i++)
|
|
result[i] = result[i] * np.scale + np.offset;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
float *Noise::perlinMap3D(float x, float y, float z, float *persistence_map)
|
|
{
|
|
float f = 1.0, g = 1.0;
|
|
size_t bufsize = sx * sy * sz;
|
|
|
|
x /= np.spread.X;
|
|
y /= np.spread.Y;
|
|
z /= np.spread.Z;
|
|
|
|
memset(result, 0, sizeof(float) * bufsize);
|
|
|
|
if (persistence_map) {
|
|
if (!persist_buf)
|
|
persist_buf = new float[bufsize];
|
|
for (size_t i = 0; i != bufsize; i++)
|
|
persist_buf[i] = 1.0;
|
|
}
|
|
|
|
for (size_t oct = 0; oct < np.octaves; oct++) {
|
|
gradientMap3D(x * f, y * f, z * f,
|
|
f / np.spread.X, f / np.spread.Y, f / np.spread.Z,
|
|
seed + np.seed + oct);
|
|
|
|
updateResults(g, persist_buf, persistence_map, bufsize);
|
|
|
|
f *= np.lacunarity;
|
|
g *= np.persist;
|
|
}
|
|
|
|
if (fabs(np.offset - 0.f) > 0.00001 || fabs(np.scale - 1.f) > 0.00001) {
|
|
for (size_t i = 0; i != bufsize; i++)
|
|
result[i] = result[i] * np.scale + np.offset;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
void Noise::updateResults(float g, float *gmap,
|
|
float *persistence_map, size_t bufsize)
|
|
{
|
|
// This looks very ugly, but it is 50-70% faster than having
|
|
// conditional statements inside the loop
|
|
if (np.flags & NOISE_FLAG_ABSVALUE) {
|
|
if (persistence_map) {
|
|
for (size_t i = 0; i != bufsize; i++) {
|
|
result[i] += gmap[i] * fabs(gradient_buf[i]);
|
|
gmap[i] *= persistence_map[i];
|
|
}
|
|
} else {
|
|
for (size_t i = 0; i != bufsize; i++)
|
|
result[i] += g * fabs(gradient_buf[i]);
|
|
}
|
|
} else {
|
|
if (persistence_map) {
|
|
for (size_t i = 0; i != bufsize; i++) {
|
|
result[i] += gmap[i] * gradient_buf[i];
|
|
gmap[i] *= persistence_map[i];
|
|
}
|
|
} else {
|
|
for (size_t i = 0; i != bufsize; i++)
|
|
result[i] += g * gradient_buf[i];
|
|
}
|
|
}
|
|
}
|