diff --git a/src/typed-geometry/detail/noise/perlin.hh b/src/typed-geometry/detail/noise/perlin.hh
index 4fe6c5e6fb4025600e06f937fd4528c699dfa42e..f17ab65d95526c95f7f41370c31a072ef6b59ed4 100644
--- a/src/typed-geometry/detail/noise/perlin.hh
+++ b/src/typed-geometry/detail/noise/perlin.hh
@@ -7,16 +7,21 @@ namespace tg
{
namespace noise
{
-// classic perlin noise (returns ScalarT in [-1, 1] (?) )
-// (see https://gist.github.com/patriciogonzalezvivo/670c22f3966e662d2f83)
-// (and https://github.com/ashima/webgl-noise/blob/master/src/classicnoise2D.glsl)
-
-// 2D
+// Classic perlin noise 1D-4D
+
+/**
+ * https://github.com/ashima/webgl-noise/blob/master/src/classicnoise2D.glsl
+ * 2D Perlin noise
+ *
+ * @param[in] p position to compute the noise at
+ *
+ * @return Noise value in the range[-1; 1]
+ */
template <class ScalarT>
-ScalarT perlin_noise(const pos<2, ScalarT>& P) // TODO allow seeding, perlin_noise_seed()!
+ScalarT perlin_noise(const pos<2, ScalarT>& p) // TODO allow seeding, perlin_noise_seed()!
{
- auto Pi = floor(pos<4, ScalarT>(P.x, P.y, P.x, P.y)) + vec<4, ScalarT>(ScalarT(0.0), ScalarT(0.0), ScalarT(1.0), ScalarT(1.0));
- auto Pf = fract(pos<4, ScalarT>(P.x, P.y, P.x, P.y)) - pos<4, ScalarT>(ScalarT(0.0), ScalarT(0.0), ScalarT(1.0), ScalarT(1.0));
+ auto Pi = floor(pos<4, ScalarT>(p.x, p.y, p.x, p.y)) + vec<4, ScalarT>(ScalarT(0.0), ScalarT(0.0), ScalarT(1.0), ScalarT(1.0));
+ auto Pf = fract(pos<4, ScalarT>(p.x, p.y, p.x, p.y)) - pos<4, ScalarT>(ScalarT(0.0), ScalarT(0.0), ScalarT(1.0), ScalarT(1.0));
Pi = mod289(Pi); // to avoid truncation effects in permutation
@@ -60,6 +65,7 @@ ScalarT perlin_noise(const ScalarT x, const ScalarT y) // TODO allow seeding, pe
return perlin_noise(pos<2, ScalarT>(x, y));
}
+// 1D perlin: calls 2D perlin noise with 0 as default 2nd coordinate
template <class ScalarT>
ScalarT perlin_noise(const pos<1, ScalarT>& p) // TODO allow seeding, perlin_noise_seed()!
{
@@ -74,15 +80,22 @@ ScalarT perlin_noise(const ScalarT x) // TODO allow seeding, perlin_noise_seed()
return perlin_noise(pos<2, ScalarT>(x, ScalarT(0)));
}
-// 3D
+/**
+ * https://gist.github.com/patriciogonzalezvivo/670c22f3966e662d2f83
+ * 3D Perlin noise
+ *
+ * @param[in] p position to compute the noise at
+ *
+ * @return Noise value in the range[-1; 1]
+ */
template <class ScalarT>
-ScalarT perlin_noise(const pos<3, ScalarT>& P)
+ScalarT perlin_noise(const pos<3, ScalarT>& p)
{
- auto Pi0 = floor(P); // integer part for indexing
+ auto Pi0 = floor(p); // integer part for indexing
auto Pi1 = Pi0 + vec<3, ScalarT>(ScalarT(1.0)); // integer part + 1
Pi0 = mod289(Pi0);
Pi1 = mod289(Pi1);
- auto Pf0 = vec<3, ScalarT>(fract(P)); // fractional part for interpolation
+ auto Pf0 = vec<3, ScalarT>(fract(p)); // fractional part for interpolation
auto Pf1 = Pf0 - vec<3, ScalarT>(ScalarT(1.0)); // fractional part - 1.0
auto ix = pos<4, ScalarT>(Pi0.x, Pi1.x, Pi0.x, Pi1.x);
auto iy = vec<4, ScalarT>(Pi0.y, Pi0.y, Pi1.y, Pi1.y);
@@ -167,15 +180,22 @@ ScalarT perlin_noise(const ScalarT x, const ScalarT y, const ScalarT z) // TODO
return perlin_noise(pos<3, ScalarT>(x, y, z));
}
-// 4D
+/**
+ * https://gist.github.com/patriciogonzalezvivo/670c22f3966e662d2f83
+ * 4D Perlin noise
+ *
+ * @param[in] p position to compute the noise at
+ *
+ * @return Noise value in the range[-1; 1]
+ */
template <class ScalarT>
-ScalarT perlin_noise(const pos<4, ScalarT>& P)
+ScalarT perlin_noise(const pos<4, ScalarT>& p)
{
- auto Pi0 = floor(P); // integer part for indexing
+ auto Pi0 = floor(p); // integer part for indexing
auto Pi1 = Pi0 + ScalarT(1.0); // integer part + 1
Pi0 = mod289(Pi0);
Pi1 = mod289(Pi1);
- auto Pf0 = vec<4, ScalarT>(fract(P)); // fractional part for interpolation
+ auto Pf0 = vec<4, ScalarT>(fract(p)); // fractional part for interpolation
auto Pf1 = Pf0 - ScalarT(1.0); // fractional part - 1.0
auto ix = pos<4, ScalarT>(Pi0.x, Pi1.x, Pi0.x, Pi1.x);
auto iy = vec<4, ScalarT>(Pi0.y, Pi0.y, Pi1.y, Pi1.y);
diff --git a/src/typed-geometry/detail/noise/simplex.hh b/src/typed-geometry/detail/noise/simplex.hh
index 6376f81b90de888c00aa4a05ec749a06166471b3..2edc20f121adb9dc1d0a7dab85d67b7e3a42100f 100644
--- a/src/typed-geometry/detail/noise/simplex.hh
+++ b/src/typed-geometry/detail/noise/simplex.hh
@@ -1,22 +1,18 @@
#pragma once
#include <typed-geometry/detail/noise_helper.hh>
-#include <typed-geometry/functions/minmax.hh>
-#include <typed-geometry/types/pos.hh>
-#include <typed-geometry/types/vec.hh>
+#include <typed-geometry/common/scalar_math.hh> // clamp(ScalarT, ..)
namespace tg
{
namespace noise
{
-// simplex noise 1D-3D
-// https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
+// Simplex noise 1D-4D
/**
+ * https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
* 1D Perlin simplex noise
*
- * Takes around 74ns on an AMD APU.
- *
- * @param[in] x ScalarT coordinate
+ * @param[in] p position to compute the noise at
*
* @return Noise value in the range[-1; 1], value of 0 on all integer coordinates.
*/
@@ -51,47 +47,14 @@ ScalarT simplex_noise(pos<1, ScalarT> const& p)
return ScalarT(0.395) * (n0 + n1);
}
-/*
-// 2D
-// https://github.com/ashima/webgl-noise/blob/master/src/noise2D.glsl
-template <class ScalarT>
-ScalarT simplex_noise(pos<2, ScalarT> const& v) // TODO allow seeding, perlin_noise_seed()!
-{
- auto const C = vec<4, ScalarT>(ScalarT(0.211324865405187), ScalarT(0.366025403784439), ScalarT(-0.577350269189626), ScalarT(0.024390243902439));
- auto i = floor(v + dot(v, vec<2, ScalarT>(C.y)));
- auto x0 = v - i + dot(i, vec<2, ScalarT>(C.x));
- auto i1 = (x0.x > x0.y) ? vec<2, ScalarT>(1, 0) : vec<2, ScalarT>(0, 1);
- auto x12 = vec<4, ScalarT>(x0.x, x0.y, x0.x, x0.y) + vec<4, ScalarT>(C.x, C.x, C.z, C.z);
- x12.x -= i1.x;
- x12.y -= i1.y;
- i = mod289(i);
- auto p = permute(permute(i.y + pos<3, ScalarT>(0, i1.y, 1)) + i.x + vec<3, ScalarT>(0, i1.x, 1));
-
- // TODO unsure from source whether this is correct
- // i believe its just supposed to be clamped to 0 element wise
- auto m = comp<3, ScalarT>(ScalarT(0.5))
- - comp<3, ScalarT>(dot(x0, x0), dot(vec<2, ScalarT>(x12), vec<2, ScalarT>(x12)),
- dot(vec<2, ScalarT>(x12.z, x12.w), vec<2, ScalarT>(x12.z, x12.w)));
- for (auto i = 0; i < 3; i++)
- m[i] = max(m[i], 0);
- m = m * m;
- m = m * m;
-
- auto x = 2 * fract(p * comp<3, ScalarT>(C.w)) - 1;
- auto h = comp<3, ScalarT>(abs(x) - ScalarT(0.5));
- auto ox = floor(x + ScalarT(0.5));
- auto a0 = comp<3, ScalarT>(x - ox);
- m *= ScalarT(1.79284291400159) - ScalarT(0.85373472095314) * (a0 * a0 + h * h);
- auto g = vec<3, ScalarT>::zero;
- g.x = a0[0] * x0[0] + h[0] * x0[1];
- // g.yz = a0.yz * x12.xz + h.yz * x12.yw;
- g.y = a0[1] * x12[0] + h[1] * x12[1];
- g.z = a0[2] * x12[2] + h[2] * x12[3];
- return 130 * dot(vec<3, ScalarT>(m), vec<3, ScalarT>(g));
-}*/
-
-// 2D simplex_noise
-// // https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
+/**
+ * https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
+ * 2D Perlin simplex noise
+ *
+ * @param[in] p position to compute the noise at
+ *
+ * @return Noise value in the range[-1; 1], value of 0 on all integer coordinates.
+ */
template <class ScalarT>
ScalarT simplex_noise(pos<2, ScalarT> const& p)
{
@@ -197,16 +160,13 @@ ScalarT simplex_noise(const ScalarT x)
}
/**
+ * https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
* 3D Perlin simplex noise
*
- * @param[in] x ScalarT coordinate
- * @param[in] y ScalarT coordinate
- * @param[in] z ScalarT coordinate
+ * @param[in] p position to compute the noise at
*
* @return Noise value in the range[-1; 1], value of 0 on all integer coordinates.
*/
-
-// See https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
template <class ScalarT>
ScalarT simplex_noise(pos<3, ScalarT> const& p)
{
@@ -366,9 +326,15 @@ ScalarT simplex_noise(ScalarT const x, ScalarT const y, ScalarT const z)
return simplex_noise(pos<3, ScalarT>(x, y, z));
}
-// 4D simplex noise
-// https://github.com/ashima/webgl-noise/blob/master/src/noise4D.glsl
-// NOTE: compared with 1D-3D simplex above, this function is slow!
+/**
+ * https://github.com/ashima/webgl-noise/blob/master/src/noise4D.glsl
+ * NOTE: compared with 1D-3D simplex, this function is rather slow
+ * 4D Perlin simplex noise
+ *
+ * @param[in] p position to compute the noise at
+ *
+ * @return Noise value in the range[-1; 1]
+ */
template <class ScalarT>
ScalarT simplex_noise(pos<4, ScalarT> const& p)
{
@@ -455,9 +421,9 @@ ScalarT simplex_noise(pos<4, ScalarT> const& p)
cm1 = cm1 * cm1;
auto a1 = dot(vec<3, ScalarT>(cm0 * cm0), vec<3, ScalarT>(dot(p0, x0), dot(p1, x1), dot(p2, x2)));
- auto ret = ScalarT(49) * (a1 + dot(vec<2, ScalarT>(cm1 * cm1), vec<2, ScalarT>(dot(p3, x3), dot(p4, x4))));
+ auto ret = ScalarT(49) * (a1 + dot(vec<2, ScalarT>(cm1 * cm1), vec<2, ScalarT>(dot(p3, x3), dot(p4, x4))));
- // TODO this should not be necessary, but in some rare cases currently is (slightly above/below 1.0: +/- 0.03..)
+ // TODO This should not be necessary, but in some rare cases currently is (slightly above/below 1.0: +/- 0.03..) (?)
return tg::clamp(ret, ScalarT(-1), ScalarT(1));
}
@@ -467,6 +433,5 @@ ScalarT simplex_noise(ScalarT const x, ScalarT const y, ScalarT const z, ScalarT
return simplex_noise(pos<4, ScalarT>(x, y, z, w));
}
-
} // namespace noise
} // namespace tg
diff --git a/src/typed-geometry/detail/noise_helper.hh b/src/typed-geometry/detail/noise_helper.hh
index 13519e371fea3f4ab27f050eb4f7ce45cabdd08a..cd3e3557fceac30cbd27169110937ef7c081e13e 100644
--- a/src/typed-geometry/detail/noise_helper.hh
+++ b/src/typed-geometry/detail/noise_helper.hh
@@ -6,6 +6,8 @@ namespace tg
{
namespace noise
{
+// Helper functions for simplex.hh and perlin.hh
+
template <class ScalarT>
ScalarT mod289(ScalarT const x)
{
@@ -50,10 +52,10 @@ pos<D, ScalarT> fade(const vec<D, ScalarT>& t)
return pos<D, ScalarT>(ret * ret * ret * (ret * (ret * ScalarT(6) - ScalarT(15)) + ScalarT(10)));
}
+// See https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/step.xhtml
template <int D, class ScalarT>
vec<D, ScalarT> step(const vec<D, ScalarT>& edge, const vec<D, ScalarT>& x)
{
- // see https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/step.xhtml
auto ret = vec<D, ScalarT>::zero;
for (auto i = 0; i < D; i++)
{
@@ -64,7 +66,7 @@ vec<D, ScalarT> step(const vec<D, ScalarT>& edge, const vec<D, ScalarT>& x)
return ret;
}
-// see https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/lessThan.xhtml
+// See https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/lessThan.xhtml
template <class ScalarT>
vec<4, ScalarT> lessThan(vec<4, ScalarT> const& x, vec<4, ScalarT> const& y)
{
@@ -108,7 +110,8 @@ vec<D, ScalarT> clamp(vec<D, ScalarT> const& v, const ScalarT minval, const Scal
}
return ret;
}
-// helper functions for simplex noise https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
+
+// Helper functions (and data) for simplex noise https://github.com/SRombauts/SimplexNoise/blob/master/src/SimplexNoise.cpp
/**
* Permutation table. This is just a random jumble of all numbers 0-255.
*