mirror of
https://github.com/g-truc/glm.git
synced 2024-11-23 09:14:34 +00:00
Updated simplex noise 3D
This commit is contained in:
Christophe Riccio
parent
477382f798
commit
082d9151d8
@ -17,11 +17,17 @@
|
||||
|
||||
namespace glm
|
||||
{
|
||||
template <typename T>
|
||||
inline detail::tvec3<T> permute(detail::tvec3<T> const & x)
|
||||
template <typename T, template<typename> class vecType>
|
||||
inline vecType<T> permute(vecType<T> const & x)
|
||||
{
|
||||
return mod(((x * T(34)) + T(1)) * x, T(289));
|
||||
}
|
||||
|
||||
template <typename T, template<typename> class vecType>
|
||||
inline vecType<T> taylorInvSqrt(vecType<T> const & r)
|
||||
{
|
||||
return T(1.79284291400159) - T(0.85373472095314) * r;
|
||||
}
|
||||
|
||||
namespace gtx{
|
||||
namespace noise
|
||||
@ -54,34 +60,123 @@ namespace noise
|
||||
detail::tvec3<T> p = permute(
|
||||
permute(i.y + detail::tvec3<T>(T(0), i1.y, T(1)))
|
||||
+ i.x + detail::tvec3<T>(T(0), i1.x, T(1)));
|
||||
/*
|
||||
|
||||
detail::tvec3<T> m = max(T(0.5) - detail::tvec3<T>(
|
||||
dot(x0, x0),
|
||||
dot(detail::tvec2<T>(x12.x, x12.y), detail::tvec2<T>(x12.x, x12.y)),
|
||||
dot(detail::tvec2<T>(x12.z, x12.w), detail::tvec2<T>(x12.z, x12.w)), T(0.0));
|
||||
dot(detail::tvec2<T>(x12.z, x12.w), detail::tvec2<T>(x12.z, x12.w))), T(0));
|
||||
m = m * m ;
|
||||
m = m * m ;
|
||||
|
||||
// Gradients: 41 points uniformly over a line, mapped onto a diamond.
|
||||
// The ring size 17*17 = 289 is close to a multiple of 41 (41*7 = 287)
|
||||
|
||||
detail::tvec3<T> x = 2.0 * fract(p * C.w) - 1.0;
|
||||
detail::tvec3<T> h = abs(x) - 0.5;
|
||||
detail::tvec3<T> ox = floor(x + 0.5);
|
||||
detail::tvec3<T> x = T(2) * fract(p * C.w) - T(1);
|
||||
detail::tvec3<T> h = abs(x) - T(0.5);
|
||||
detail::tvec3<T> ox = floor(x + T(0.5));
|
||||
detail::tvec3<T> a0 = x - ox;
|
||||
|
||||
// Normalise gradients implicitly by scaling m
|
||||
// Inlined for speed: m *= taylorInvSqrt( a0*a0 + h*h );
|
||||
m *= 1.79284291400159 - 0.85373472095314 * (a0 * a0 + h * h);
|
||||
m *= T(1.79284291400159) - T(0.85373472095314) * (a0 * a0 + h * h);
|
||||
|
||||
// Compute final noise value at P
|
||||
detail::tvec3<T> g;
|
||||
g.x = a0.x * x0.x + h.x * x0.y;
|
||||
g.yz = a0.yz * x12.xz + h.yz * x12.yw;
|
||||
return 130.0 * dot(m, g);
|
||||
*/
|
||||
//g.yz = a0.yz * x12.xz + h.yz * x12.yw;
|
||||
g.y = a0.y * x12.x + h.y * x12.y;
|
||||
g.z = a0.z * x12.z + h.z * x12.w;
|
||||
return T(130) * dot(m, g);
|
||||
}
|
||||
|
||||
template <typename T>
|
||||
inline T snoise(glm::detail::tvec3<T> const & v)
|
||||
{
|
||||
detail::tvec2<T> const C = detail::tvec2<T>(1.0 / 6.0, 1.0 / 3.0);
|
||||
detail::tvec4<T> const D = detail::tvec4<T>(0.0, 0.5, 1.0, 2.0);
|
||||
|
||||
// First corner
|
||||
detail::tvec3<T> i = floor(v + dot(v, C.y));
|
||||
detail::tvec3<T> x0 = v - i + dot(i, C.x);
|
||||
|
||||
// Other corners
|
||||
detail::tvec3<T> g = step(x0.yzx, x0.xyz);
|
||||
detail::tvec3<T> l = 1.0 - g;
|
||||
detail::tvec3<T> i1 = min( g.xyz, l.zxy );
|
||||
detail::tvec3<T> i2 = max( g.xyz, l.zxy );
|
||||
|
||||
// x0 = x0 - 0.0 + 0.0 * C.xxx;
|
||||
// x1 = x0 - i1 + 1.0 * C.xxx;
|
||||
// x2 = x0 - i2 + 2.0 * C.xxx;
|
||||
// x3 = x0 - 1.0 + 3.0 * C.xxx;
|
||||
detail::tvec3<T> x1 = x0 - i1 + C.x;
|
||||
detail::tvec3<T> x2 = x0 - i2 + C.y; // 2.0*C.x = 1/3 = C.y
|
||||
detail::tvec3<T> x3 = x0 - D.y; // -1.0+3.0*C.x = -0.5 = -D.y
|
||||
|
||||
// Permutations
|
||||
i = mod(i, T(289));
|
||||
detail::tvec4<T> p = permute(permute(permute(
|
||||
i.z + detail::tvec4<T>(0.0, i1.z, i2.z, 1.0)) +
|
||||
i.y + detail::tvec4<T>(0.0, i1.y, i2.y, 1.0)) +
|
||||
i.x + detail::tvec4<T>(0.0, i1.x, i2.x, 1.0));
|
||||
|
||||
// Gradients: 7x7 points over a square, mapped onto an octahedron.
|
||||
// The ring size 17*17 = 289 is close to a multiple of 49 (49*6 = 294)
|
||||
T n_ = T(0.142857142857); // 1.0/7.0
|
||||
detail::tvec3<T> ns = n_ * D.wyz - D.xzx;
|
||||
|
||||
detail::tvec4<T> j = p - T(49) * floor(p * ns.z * ns.z); // mod(p,7*7)
|
||||
|
||||
detail::tvec4<T> x_ = floor(j * ns.z);
|
||||
detail::tvec4<T> y_ = floor(j - T(7) * x_ ); // mod(j,N)
|
||||
|
||||
detail::tvec4<T> x = x_ * ns.x + ns;
|
||||
detail::tvec4<T> y = y_ * ns.x + ns;
|
||||
detail::tvec4<T> h = T(1) - abs(x) - abs(y);
|
||||
|
||||
detail::tvec4<T> b0 = detail::tvec4<T>(x.xy, y.xy);
|
||||
detail::tvec4<T> b1 = detail::tvec4<T>(x.zw, y.zw);
|
||||
|
||||
//vec4 s0 = vec4(lessThan(b0,0.0))*2.0 - 1.0;
|
||||
//vec4 s1 = vec4(lessThan(b1,0.0))*2.0 - 1.0;
|
||||
detail::tvec4<T> s0 = floor(b0) * T(2) + T(1);
|
||||
detail::tvec4<T> s1 = floor(b1) * T(2) + T(1);
|
||||
detail::tvec4<T> sh = -step(h, detail::tvec4<T>(0));
|
||||
|
||||
detail::tvec4<T> a0 = b0 + s0 * sh.xxyy;
|
||||
detail::tvec4<T> a1 = b1 + s1 * sh.zzww;
|
||||
|
||||
detail::tvec3<T> p0 = vec3(a0.xy, h.x);
|
||||
detail::tvec3<T> p1 = vec3(a0.zw, h.y);
|
||||
detail::tvec3<T> p2 = vec3(a1.xy, h.z);
|
||||
detail::tvec3<T> p3 = vec3(a1.zw, h.w);
|
||||
|
||||
//Normalise gradients
|
||||
detail::tvec4<T> norm = taylorInvSqrt(detail::tvec4<T>(
|
||||
dot(p0, p0),
|
||||
dot(p1, p1),
|
||||
dot(p2, p2),
|
||||
dot(p3, p3)));
|
||||
p0 *= norm.x;
|
||||
p1 *= norm.y;
|
||||
p2 *= norm.z;
|
||||
p3 *= norm.w;
|
||||
|
||||
// Mix final noise value
|
||||
vec4 m = max(T(0.6) - detail::tvec4<T>(
|
||||
dot(x0, x0),
|
||||
dot(x1, x1),
|
||||
dot(x2, x2),
|
||||
dot(x3, x3)), T(0));
|
||||
m = m * m;
|
||||
return T(42) * dot(m * m, detail::tvec4<T>(
|
||||
dot(p0, x0),
|
||||
dot(p1, x1),
|
||||
dot(p2, x2),
|
||||
dot(p3, x3)));
|
||||
}
|
||||
|
||||
|
||||
}//namespace noise
|
||||
}//namespace gtx
|
||||
}//namespace glm
|
||||
|
||||
Loading…
Reference in New Issue
Block a user