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authordaoge_cmd <3523206925@qq.com>2026-03-01 12:16:08 +0800
committerdaoge_cmd <3523206925@qq.com>2026-03-01 12:16:08 +0800
commitb691c43c44ff180d10e7d4a9afc83b98551ff586 (patch)
tree3e9849222cbc6ba49f2f1fc6e5fe7179632c7390 /Minecraft.World/SimplexNoise.cpp
parentdef8cb415354ac390b7e89052a50605285f1aca9 (diff)
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-rw-r--r--Minecraft.World/SimplexNoise.cpp476
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diff --git a/Minecraft.World/SimplexNoise.cpp b/Minecraft.World/SimplexNoise.cpp
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+++ b/Minecraft.World/SimplexNoise.cpp
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+#include "stdafx.h"
+#include "SimplexNoise.h"
+
+int SimplexNoise::grad3[12][3] = { { 1, 1, 0 }, { -1, 1, 0 }, { 1, -1, 0 }, { -1, -1, 0 }, { 1, 0, 1 }, { -1, 0, 1 }, { 1, 0, -1 }, { -1, 0, -1 }, { 0, 1, 1 }, { 0, -1, 1 }, { 0, 1, -1 }, { 0, -1, -1 } };
+
+double SimplexNoise::F2 = 0.5 * (sqrt(3.0) - 1.0);
+double SimplexNoise::G2 = (3.0 - sqrt(3.0)) / 6.0;
+double SimplexNoise::F3 = 1.0 / 3.0;
+double SimplexNoise::G3 = 1.0 / 6.0;
+
+SimplexNoise::SimplexNoise()
+{
+ Random random;
+ init(&random);
+}
+
+SimplexNoise::SimplexNoise(Random *random)
+{
+ init(random);
+}
+
+void SimplexNoise::init(Random *random)
+{
+ p = new int[512];
+
+ xo = random->nextDouble() * 256;
+ yo = random->nextDouble() * 256;
+ zo = random->nextDouble() * 256;
+ for (int i = 0; i < 256; i++)
+ {
+ p[i] = i;
+ }
+
+ for (int i = 0; i < 256; i++)
+ {
+ int j = random->nextInt(256 - i) + i;
+ int tmp = p[i];
+ p[i] = p[j];
+ p[j] = tmp;
+
+ p[i + 256] = p[i];
+ }
+}
+
+SimplexNoise::~SimplexNoise()
+{
+ delete [] p;
+}
+
+int SimplexNoise::fastfloor(double x)
+{
+ return x > 0 ? (int) x : (int) x - 1;
+}
+
+double SimplexNoise::dot(int *g, double x, double y)
+{
+ return g[0] * x + g[1] * y;
+}
+
+double SimplexNoise::dot(int *g, double x, double y, double z)
+{
+ return g[0] * x + g[1] * y + g[2] * z;
+}
+
+double SimplexNoise::getValue(double xin, double yin)
+{
+ double n0, n1, n2; // Noise contributions from the three corners
+ // Skew the input space to determine which simplex cell we're in
+ double s = (xin + yin) * F2; // Hairy factor for 2D
+ int i = fastfloor(xin + s);
+ int j = fastfloor(yin + s);
+ double t = (i + j) * G2;
+ double X0 = i - t; // Unskew the cell origin back to (x,y) space
+ double Y0 = j - t;
+ double x0 = xin - X0; // The x,y distances from the cell origin
+ double y0 = yin - Y0;
+ // For the 2D case, the simplex shape is an equilateral triangle.
+ // Determine which simplex we are in.
+ int i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords
+ if (x0 > y0) {
+ i1 = 1;
+ j1 = 0;
+ } // lower triangle, XY order: (0,0)->(1,0)->(1,1)
+ else {
+ i1 = 0;
+ j1 = 1;
+ } // upper triangle, YX order: (0,0)->(0,1)->(1,1)
+ // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
+ // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
+ // c = (3-sqrt(3))/6
+ double x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords
+ double y1 = y0 - j1 + G2;
+ double x2 = x0 - 1.0 + 2.0 * G2; // Offsets for last corner in (x,y) unskewed coords
+ double y2 = y0 - 1.0 + 2.0 * G2;
+ // Work out the hashed gradient indices of the three simplex corners
+ int ii = i & 255;
+ int jj = j & 255;
+ int gi0 = p[ii + p[jj]] % 12;
+ int gi1 = p[ii + i1 + p[jj + j1]] % 12;
+ int gi2 = p[ii + 1 + p[jj + 1]] % 12;
+ // Calculate the contribution from the three corners
+ double t0 = 0.5 - x0 * x0 - y0 * y0;
+ if (t0 < 0) n0 = 0.0;
+ else {
+ t0 *= t0;
+ n0 = t0 * t0 * dot(grad3[gi0], x0, y0); // (x,y) of grad3 used for 2D gradient
+ }
+ double t1 = 0.5 - x1 * x1 - y1 * y1;
+ if (t1 < 0) n1 = 0.0;
+ else {
+ t1 *= t1;
+ n1 = t1 * t1 * dot(grad3[gi1], x1, y1);
+ }
+ double t2 = 0.5 - x2 * x2 - y2 * y2;
+ if (t2 < 0) n2 = 0.0;
+ else {
+ t2 *= t2;
+ n2 = t2 * t2 * dot(grad3[gi2], x2, y2);
+ }
+ // Add contributions from each corner to get the final noise value.
+ // The result is scaled to return values in the interval [-1,1].
+ return 70.0 * (n0 + n1 + n2);
+}
+
+double SimplexNoise::getValue(double xin, double yin, double zin)
+{
+ double n0, n1, n2, n3;
+ double s = (xin + yin + zin) * F3;
+ int i = fastfloor(xin + s);
+ int j = fastfloor(yin + s);
+ int k = fastfloor(zin + s);
+
+ double t = (i + j + k) * G3;
+ double X0 = i - t;
+ double Y0 = j - t;
+ double Z0 = k - t;
+ double x0 = xin - X0;
+ double y0 = yin - Y0;
+ double z0 = zin - Z0;
+ int i1, j1, k1;
+ int i2, j2, k2;
+ if (x0 >= y0)
+ {
+ if (y0 >= z0)
+ {
+ i1 = 1;
+ j1 = 0;
+ k1 = 0;
+ i2 = 1;
+ j2 = 1;
+ k2 = 0;
+ } // X Y Z order
+ else if (x0 >= z0)
+ {
+ i1 = 1;
+ j1 = 0;
+ k1 = 0;
+ i2 = 1;
+ j2 = 0;
+ k2 = 1;
+ } // X Z Y order
+ else
+ {
+ i1 = 0;
+ j1 = 0;
+ k1 = 1;
+ i2 = 1;
+ j2 = 0;
+ k2 = 1;
+ } // Z X Y order
+ }
+ else
+ { // x0<y0
+ if (y0 < z0)
+ {
+ i1 = 0;
+ j1 = 0;
+ k1 = 1;
+ i2 = 0;
+ j2 = 1;
+ k2 = 1;
+ } // Z Y X order
+ else if (x0 < z0)
+ {
+ i1 = 0;
+ j1 = 1;
+ k1 = 0;
+ i2 = 0;
+ j2 = 1;
+ k2 = 1;
+ } // Y Z X order
+ else
+ {
+ i1 = 0;
+ j1 = 1;
+ k1 = 0;
+ i2 = 1;
+ j2 = 1;
+ k2 = 0;
+ } // Y X Z order
+ }
+ // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z),
+ // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and
+ // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where
+ // c = 1/6.
+
+ double x1 = x0 - i1 + G3; // Offsets for second corner in (x,y,z) coords
+ double y1 = y0 - j1 + G3;
+ double z1 = z0 - k1 + G3;
+ double x2 = x0 - i2 + 2.0 * G3; // Offsets for third corner in (x,y,z) coords
+ double y2 = y0 - j2 + 2.0 * G3;
+ double z2 = z0 - k2 + 2.0 * G3;
+ double x3 = x0 - 1.0 + 3.0 * G3; // Offsets for last corner in (x,y,z) coords
+ double y3 = y0 - 1.0 + 3.0 * G3;
+ double z3 = z0 - 1.0 + 3.0 * G3;
+ // Work out the hashed gradient indices of the four simplex corners
+ int ii = i & 255;
+ int jj = j & 255;
+ int kk = k & 255;
+ int gi0 = p[ii + p[jj + p[kk]]] % 12;
+ int gi1 = p[ii + i1 + p[jj + j1 + p[kk + k1]]] % 12;
+ int gi2 = p[ii + i2 + p[jj + j2 + p[kk + k2]]] % 12;
+ int gi3 = p[ii + 1 + p[jj + 1 + p[kk + 1]]] % 12;
+ // Calculate the contribution from the four corners
+ double t0 = 0.6 - x0 * x0 - y0 * y0 - z0 * z0;
+ if (t0 < 0) n0 = 0.0;
+ else
+ {
+ t0 *= t0;
+ n0 = t0 * t0 * dot(grad3[gi0], x0, y0, z0);
+ }
+ double t1 = 0.6 - x1 * x1 - y1 * y1 - z1 * z1;
+ if (t1 < 0) n1 = 0.0;
+ else
+ {
+ t1 *= t1;
+ n1 = t1 * t1 * dot(grad3[gi1], x1, y1, z1);
+ }
+ double t2 = 0.6 - x2 * x2 - y2 * y2 - z2 * z2;
+ if (t2 < 0) n2 = 0.0;
+ else
+ {
+ t2 *= t2;
+ n2 = t2 * t2 * dot(grad3[gi2], x2, y2, z2);
+ }
+ double t3 = 0.6 - x3 * x3 - y3 * y3 - z3 * z3;
+ if (t3 < 0) n3 = 0.0;
+ else
+ {
+ t3 *= t3;
+ n3 = t3 * t3 * dot(grad3[gi3], x3, y3, z3);
+ }
+ // Add contributions from each corner to get the final noise value.
+ // The result is scaled to stay just inside [-1,1]
+ return 32.0 * (n0 + n1 + n2 + n3);
+}
+
+void SimplexNoise::add(doubleArray buffer, double _x, double _y, int xSize, int ySize, double xs, double ys, double pow)
+{
+ int pp = 0;
+ for (int xx = 0; xx < xSize; xx++)
+ {
+ double xin = (_x + xx) * xs + xo;
+ for (int yy = 0; yy < ySize; yy++)
+ {
+ double yin = (_y + yy) * ys + yo;
+
+ double n0, n1, n2;
+ double s = (xin + yin) * F2; // Hairy factor for 2D
+ int i = fastfloor(xin + s);
+ int j = fastfloor(yin + s);
+ double t = (i + j) * G2;
+ double X0 = i - t; // Unskew the cell origin back to (x,y) space
+ double Y0 = j - t;
+ double x0 = xin - X0; // The x,y distances from the cell origin
+ double y0 = yin - Y0;
+ // For the 2D case, the simplex shape is an equilateral triangle.
+ // Determine which simplex we are in.
+ int i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords
+ if (x0 > y0)
+ {
+ i1 = 1;
+ j1 = 0;
+ } // lower triangle, XY order: (0,0)->(1,0)->(1,1)
+ else
+ {
+ i1 = 0;
+ j1 = 1;
+ } // upper triangle, YX order: (0,0)->(0,1)->(1,1)
+ // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
+ // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
+ // c = (3-sqrt(3))/6
+ double x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords
+ double y1 = y0 - j1 + G2;
+ double x2 = x0 - 1.0 + 2.0 * G2; // Offsets for last corner in (x,y) unskewed coords
+ double y2 = y0 - 1.0 + 2.0 * G2;
+ // Work out the hashed gradient indices of the three simplex corners
+ int ii = i & 255;
+ int jj = j & 255;
+ int gi0 = p[ii + p[jj]] % 12;
+ int gi1 = p[ii + i1 + p[jj + j1]] % 12;
+ int gi2 = p[ii + 1 + p[jj + 1]] % 12;
+ // Calculate the contribution from the three corners
+ double t0 = 0.5 - x0 * x0 - y0 * y0;
+ if (t0 < 0) n0 = 0.0;
+ else
+ {
+ t0 *= t0;
+ n0 = t0 * t0 * dot(grad3[gi0], x0, y0); // (x,y) of grad3 used for 2D gradient
+ }
+ double t1 = 0.5 - x1 * x1 - y1 * y1;
+ if (t1 < 0) n1 = 0.0;
+ else
+ {
+ t1 *= t1;
+ n1 = t1 * t1 * dot(grad3[gi1], x1, y1);
+ }
+ double t2 = 0.5 - x2 * x2 - y2 * y2;
+ if (t2 < 0) n2 = 0.0;
+ else
+ {
+ t2 *= t2;
+ n2 = t2 * t2 * dot(grad3[gi2], x2, y2);
+ }
+ // Add contributions from each corner to get the final noise value.
+ // The result is scaled to return values in the interval [-1,1].
+ buffer[pp++] += (70.0 * (n0 + n1 + n2))*pow;
+ }
+ }
+
+}
+void SimplexNoise::add(doubleArray buffer, double _x, double _y, double _z, int xSize, int ySize, int zSize, double xs, double ys, double zs, double pow)
+{
+ int pp = 0;
+ for (int xx = 0; xx < xSize; xx++)
+ {
+ double xin = (_x + xx) * xs + xo;
+ for (int zz = 0; zz < zSize; zz++)
+ {
+ double zin = (_z + zz) * zs + zo;
+ for (int yy = 0; yy < ySize; yy++)
+ {
+ double yin = (_y + yy) * ys + yo;
+
+ double n0, n1, n2, n3;
+ double s = (xin + yin + zin) * F3;
+ int i = fastfloor(xin + s);
+ int j = fastfloor(yin + s);
+ int k = fastfloor(zin + s);
+ double t = (i + j + k) * G3;
+ double X0 = i - t;
+ double Y0 = j - t;
+ double Z0 = k - t;
+ double x0 = xin - X0;
+ double y0 = yin - Y0;
+ double z0 = zin - Z0;
+ int i1, j1, k1;
+ int i2, j2, k2;
+ if (x0 >= y0)
+ {
+ if (y0 >= z0)
+ {
+ i1 = 1;
+ j1 = 0;
+ k1 = 0;
+ i2 = 1;
+ j2 = 1;
+ k2 = 0;
+ } // X Y Z order
+ else if (x0 >= z0)
+ {
+ i1 = 1;
+ j1 = 0;
+ k1 = 0;
+ i2 = 1;
+ j2 = 0;
+ k2 = 1;
+ } // X Z Y order
+ else
+ {
+ i1 = 0;
+ j1 = 0;
+ k1 = 1;
+ i2 = 1;
+ j2 = 0;
+ k2 = 1;
+ } // Z X Y order
+ }
+ else
+ { // x0<y0
+ if (y0 < z0)
+ {
+ i1 = 0;
+ j1 = 0;
+ k1 = 1;
+ i2 = 0;
+ j2 = 1;
+ k2 = 1;
+ } // Z Y X order
+ else if (x0 < z0)
+ {
+ i1 = 0;
+ j1 = 1;
+ k1 = 0;
+ i2 = 0;
+ j2 = 1;
+ k2 = 1;
+ } // Y Z X order
+ else
+ {
+ i1 = 0;
+ j1 = 1;
+ k1 = 0;
+ i2 = 1;
+ j2 = 1;
+ k2 = 0;
+ } // Y X Z order
+ }
+ // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z),
+ // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and
+ // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where
+ // c = 1/6.
+
+ double x1 = x0 - i1 + G3; // Offsets for second corner in (x,y,z) coords
+ double y1 = y0 - j1 + G3;
+ double z1 = z0 - k1 + G3;
+ double x2 = x0 - i2 + 2.0 * G3; // Offsets for third corner in (x,y,z) coords
+ double y2 = y0 - j2 + 2.0 * G3;
+ double z2 = z0 - k2 + 2.0 * G3;
+ double x3 = x0 - 1.0 + 3.0 * G3; // Offsets for last corner in (x,y,z) coords
+ double y3 = y0 - 1.0 + 3.0 * G3;
+ double z3 = z0 - 1.0 + 3.0 * G3;
+ // Work out the hashed gradient indices of the four simplex corners
+ int ii = i & 255;
+ int jj = j & 255;
+ int kk = k & 255;
+ int gi0 = p[ii + p[jj + p[kk]]] % 12;
+ int gi1 = p[ii + i1 + p[jj + j1 + p[kk + k1]]] % 12;
+ int gi2 = p[ii + i2 + p[jj + j2 + p[kk + k2]]] % 12;
+ int gi3 = p[ii + 1 + p[jj + 1 + p[kk + 1]]] % 12;
+ // Calculate the contribution from the four corners
+ double t0 = 0.6 - x0 * x0 - y0 * y0 - z0 * z0;
+ if (t0 < 0) n0 = 0.0;
+ else
+ {
+ t0 *= t0;
+ n0 = t0 * t0 * dot(grad3[gi0], x0, y0, z0);
+ }
+ double t1 = 0.6 - x1 * x1 - y1 * y1 - z1 * z1;
+ if (t1 < 0) n1 = 0.0;
+ else
+ {
+ t1 *= t1;
+ n1 = t1 * t1 * dot(grad3[gi1], x1, y1, z1);
+ }
+ double t2 = 0.6 - x2 * x2 - y2 * y2 - z2 * z2;
+ if (t2 < 0) n2 = 0.0;
+ else
+ {
+ t2 *= t2;
+ n2 = t2 * t2 * dot(grad3[gi2], x2, y2, z2);
+ }
+ double t3 = 0.6 - x3 * x3 - y3 * y3 - z3 * z3;
+ if (t3 < 0) n3 = 0.0;
+ else
+ {
+ t3 *= t3;
+ n3 = t3 * t3 * dot(grad3[gi3], x3, y3, z3);
+ }
+ // Add contributions from each corner to get the final noise value.
+ // The result is scaled to stay just inside [-1,1]
+ buffer[pp++] += (32.0 * (n0 + n1 + n2 + n3))*pow;
+ }
+ }
+ }
+} \ No newline at end of file