Re-add 3D and 4D Simplex Noise.

This partially revert 97806f87c018d77d44d30ae2cf3c4384ab9f3047

src/libraries/noise1234/noise1234.cpp

@@ -11,6 +11,8 @@
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // General Public License for more details.
 
+// Modified by the LOVE Development Team to use double precision.
+
 /** \file
 		\brief Implements the Noise1234 class for producing Perlin noise.
 		\author Stefan Gustavson ([email protected])

src/libraries/noise1234/noise1234.h

@@ -11,6 +11,8 @@
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // General Public License for more details.
 
+// Modified by the LOVE Development Team to use double precision.
+
 /** \file
 		\brief Declares the Noise1234 class for producing Perlin noise.
 		\author Stefan Gustavson ([email protected])

src/libraries/noise1234/simplexnoise1234.cpp

@@ -13,8 +13,7 @@
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // General Public License for more details.
 
-// Modified by the LOVE Development Team to remove 3D and 4D implementations due
-// to patent issues.
+// Modified by the LOVE Development Team to use double precision.
 
 /** \file
 		\brief Implements the SimplexNoise1234 class for producing Perlin simplex noise.
@@ -117,6 +116,34 @@ double  SimplexNoise1234::grad( int hash, double x, double y ) {
     return ((h&1)? -u : u) + ((h&2)? -2.0*v : 2.0*v);
 }
 
+double  SimplexNoise1234::grad( int hash, double x, double y , double z ) {
+    int h = hash & 15;     // Convert low 4 bits of hash code into 12 simple
+    double u = h<8 ? x : y; // gradient directions, and compute dot product.
+    double v = h<4 ? y : h==12||h==14 ? x : z; // Fix repeats at h = 12 to 15
+    return ((h&1)? -u : u) + ((h&2)? -v : v);
+}
+
+double  SimplexNoise1234::grad( int hash, double x, double y, double z, double t ) {
+    int h = hash & 31;      // Convert low 5 bits of hash code into 32 simple
+    double u = h<24 ? x : y; // gradient directions, and compute dot product.
+    double v = h<16 ? y : z;
+    double w = h<8 ? z : t;
+    return ((h&1)? -u : u) + ((h&2)? -v : v) + ((h&4)? -w : w);
+}
+
+// A lookup table to traverse the simplex around a given point in 4D.
+// Details can be found where this table is used, in the 4D noise method.
+/* TODO: This should not be required, backport it from Bill's GLSL code! */
+static unsigned char simplex[64][4] = {
+    {0,1,2,3},{0,1,3,2},{0,0,0,0},{0,2,3,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,2,3,0},
+    {0,2,1,3},{0,0,0,0},{0,3,1,2},{0,3,2,1},{0,0,0,0},{0,0,0,0},{0,0,0,0},{1,3,2,0},
+    {0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},
+    {1,2,0,3},{0,0,0,0},{1,3,0,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,3,0,1},{2,3,1,0},
+    {1,0,2,3},{1,0,3,2},{0,0,0,0},{0,0,0,0},{0,0,0,0},{2,0,3,1},{0,0,0,0},{2,1,3,0},
+    {0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0},
+    {2,0,1,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,0,1,2},{3,0,2,1},{0,0,0,0},{3,1,2,0},
+    {2,1,0,3},{0,0,0,0},{0,0,0,0},{0,0,0,0},{3,1,0,2},{0,0,0,0},{3,2,0,1},{3,2,1,0}};
+
 // 1D simplex noise
 float SimplexNoise1234::noise(double x) {
 
@@ -206,3 +233,238 @@ float SimplexNoise1234::noise(double x, double y) {
     // The result is scaled to return values in the interval [-1,1].
     return 45.23f * (n0 + n1 + n2); // TODO: The scale factor is preliminary!
   }
+
+// 3D simplex noise
+float SimplexNoise1234::noise(double x, double y, double z) {
+
+    // Simple skewing factors for the 3D case
+#define F3 0.333333333
+#define G3 0.166666667
+
+    double n0, n1, n2, n3; // Noise contributions from the four corners
+
+    // Skew the input space to determine which simplex cell we're in
+    double s = (x+y+z)*F3; // Very nice and simple skew factor for 3D
+    double xs = x+s;
+    double ys = y+s;
+    double zs = z+s;
+    int i = FASTFLOOR(xs);
+    int j = FASTFLOOR(ys);
+    int k = FASTFLOOR(zs);
+
+    double t = (float)(i+j+k)*G3; 
+    double X0 = i-t; // Unskew the cell origin back to (x,y,z) space
+    double Y0 = j-t;
+    double Z0 = k-t;
+    double x0 = x-X0; // The x,y,z distances from the cell origin
+    double y0 = y-Y0;
+    double z0 = z-Z0;
+
+    // For the 3D case, the simplex shape is a slightly irregular tetrahedron.
+    // Determine which simplex we are in.
+    int i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords
+    int i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords
+
+    /* This code would benefit from a backport from the GLSL version! */
+    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 + 2.0f*G3; // Offsets for third corner in (x,y,z) coords
+    double y2 = y0 - j2 + 2.0f*G3;
+    double z2 = z0 - k2 + 2.0f*G3;
+    double x3 = x0 - 1.0f + 3.0f*G3; // Offsets for last corner in (x,y,z) coords
+    double y3 = y0 - 1.0f + 3.0f*G3;
+    double z3 = z0 - 1.0f + 3.0f*G3;
+
+    // Wrap the integer indices at 256, to avoid indexing perm[] out of bounds
+    int ii = i & 0xff;
+    int jj = j & 0xff;
+    int kk = k & 0xff;
+
+    // Calculate the contribution from the four corners
+    double t0 = 0.6f - x0*x0 - y0*y0 - z0*z0;
+    if(t0 < 0.0f) n0 = 0.0f;
+    else {
+        t0 *= t0;
+        n0 = t0 * t0 * grad(perm[ii+perm[jj+perm[kk]]], x0, y0, z0);
+    }
+
+    double t1 = 0.6f - x1*x1 - y1*y1 - z1*z1;
+    if(t1 < 0.0f) n1 = 0.0f;
+    else {
+        t1 *= t1;
+        n1 = t1 * t1 * grad(perm[ii+i1+perm[jj+j1+perm[kk+k1]]], x1, y1, z1);
+    }
+
+    double t2 = 0.6f - x2*x2 - y2*y2 - z2*z2;
+    if(t2 < 0.0f) n2 = 0.0f;
+    else {
+        t2 *= t2;
+        n2 = t2 * t2 * grad(perm[ii+i2+perm[jj+j2+perm[kk+k2]]], x2, y2, z2);
+    }
+
+    double t3 = 0.6f - x3*x3 - y3*y3 - z3*z3;
+    if(t3<0.0f) n3 = 0.0f;
+    else {
+        t3 *= t3;
+        n3 = t3 * t3 * grad(perm[ii+1+perm[jj+1+perm[kk+1]]], 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 32.74f * (n0 + n1 + n2 + n3); // TODO: The scale factor is preliminary!
+}
+
+
+// 4D simplex noise
+float SimplexNoise1234::noise(double x, double y, double z, double w) {
+
+    // The skewing and unskewing factors are hairy again for the 4D case
+#define F4 0.309016994 // F4 = (Math.sqrt(5.0)-1.0)/4.0
+#define G4 0.138196601 // G4 = (5.0-Math.sqrt(5.0))/20.0
+
+    double n0, n1, n2, n3, n4; // Noise contributions from the five corners
+
+    // Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in
+    double s = (x + y + z + w) * F4; // Factor for 4D skewing
+    double xs = x + s;
+    double ys = y + s;
+    double zs = z + s;
+    double ws = w + s;
+    int i = FASTFLOOR(xs);
+    int j = FASTFLOOR(ys);
+    int k = FASTFLOOR(zs);
+    int l = FASTFLOOR(ws);
+
+    double t = (i + j + k + l) * G4; // Factor for 4D unskewing
+    double X0 = i - t; // Unskew the cell origin back to (x,y,z,w) space
+    double Y0 = j - t;
+    double Z0 = k - t;
+    double W0 = l - t;
+
+    double x0 = x - X0;  // The x,y,z,w distances from the cell origin
+    double y0 = y - Y0;
+    double z0 = z - Z0;
+    double w0 = w - W0;
+
+    // For the 4D case, the simplex is a 4D shape I won't even try to describe.
+    // To find out which of the 24 possible simplices we're in, we need to
+    // determine the magnitude ordering of x0, y0, z0 and w0.
+    // The method below is a good way of finding the ordering of x,y,z,w and
+    // then find the correct traversal order for the simplex we’re in.
+    // First, six pair-wise comparisons are performed between each possible pair
+    // of the four coordinates, and the results are used to add up binary bits
+    // for an integer index.
+    int c1 = (x0 > y0) ? 32 : 0;
+    int c2 = (x0 > z0) ? 16 : 0;
+    int c3 = (y0 > z0) ? 8 : 0;
+    int c4 = (x0 > w0) ? 4 : 0;
+    int c5 = (y0 > w0) ? 2 : 0;
+    int c6 = (z0 > w0) ? 1 : 0;
+    int c = c1 + c2 + c3 + c4 + c5 + c6;
+
+    int i1, j1, k1, l1; // The integer offsets for the second simplex corner
+    int i2, j2, k2, l2; // The integer offsets for the third simplex corner
+    int i3, j3, k3, l3; // The integer offsets for the fourth simplex corner
+
+    // simplex[c] is a 4-vector with the numbers 0, 1, 2 and 3 in some order.
+    // Many values of c will never occur, since e.g. x>y>z>w makes x<z, y<w and x<w
+    // impossible. Only the 24 indices which have non-zero entries make any sense.
+    // We use a thresholding to set the coordinates in turn from the largest magnitude.
+    // The number 3 in the "simplex" array is at the position of the largest coordinate.
+    i1 = simplex[c][0]>=3 ? 1 : 0;
+    j1 = simplex[c][1]>=3 ? 1 : 0;
+    k1 = simplex[c][2]>=3 ? 1 : 0;
+    l1 = simplex[c][3]>=3 ? 1 : 0;
+    // The number 2 in the "simplex" array is at the second largest coordinate.
+    i2 = simplex[c][0]>=2 ? 1 : 0;
+    j2 = simplex[c][1]>=2 ? 1 : 0;
+    k2 = simplex[c][2]>=2 ? 1 : 0;
+    l2 = simplex[c][3]>=2 ? 1 : 0;
+    // The number 1 in the "simplex" array is at the second smallest coordinate.
+    i3 = simplex[c][0]>=1 ? 1 : 0;
+    j3 = simplex[c][1]>=1 ? 1 : 0;
+    k3 = simplex[c][2]>=1 ? 1 : 0;
+    l3 = simplex[c][3]>=1 ? 1 : 0;
+    // The fifth corner has all coordinate offsets = 1, so no need to look that up.
+
+    double x1 = x0 - i1 + G4; // Offsets for second corner in (x,y,z,w) coords
+    double y1 = y0 - j1 + G4;
+    double z1 = z0 - k1 + G4;
+    double w1 = w0 - l1 + G4;
+    double x2 = x0 - i2 + 2.0f*G4; // Offsets for third corner in (x,y,z,w) coords
+    double y2 = y0 - j2 + 2.0f*G4;
+    double z2 = z0 - k2 + 2.0f*G4;
+    double w2 = w0 - l2 + 2.0f*G4;
+    double x3 = x0 - i3 + 3.0f*G4; // Offsets for fourth corner in (x,y,z,w) coords
+    double y3 = y0 - j3 + 3.0f*G4;
+    double z3 = z0 - k3 + 3.0f*G4;
+    double w3 = w0 - l3 + 3.0f*G4;
+    double x4 = x0 - 1.0f + 4.0f*G4; // Offsets for last corner in (x,y,z,w) coords
+    double y4 = y0 - 1.0f + 4.0f*G4;
+    double z4 = z0 - 1.0f + 4.0f*G4;
+    double w4 = w0 - 1.0f + 4.0f*G4;
+
+    // Wrap the integer indices at 256, to avoid indexing perm[] out of bounds
+    int ii = i & 0xff;
+    int jj = j & 0xff;
+    int kk = k & 0xff;
+    int ll = l & 0xff;
+
+    // Calculate the contribution from the five corners
+    double t0 = 0.6f - x0*x0 - y0*y0 - z0*z0 - w0*w0;
+    if(t0 < 0.0f) n0 = 0.0f;
+    else {
+        t0 *= t0;
+        n0 = t0 * t0 * grad(perm[ii+perm[jj+perm[kk+perm[ll]]]], x0, y0, z0, w0);
+    }
+
+    double t1 = 0.6f - x1*x1 - y1*y1 - z1*z1 - w1*w1;
+    if(t1 < 0.0f) n1 = 0.0f;
+    else {
+        t1 *= t1;
+        n1 = t1 * t1 * grad(perm[ii+i1+perm[jj+j1+perm[kk+k1+perm[ll+l1]]]], x1, y1, z1, w1);
+    }
+
+    double t2 = 0.6f - x2*x2 - y2*y2 - z2*z2 - w2*w2;
+    if(t2 < 0.0f) n2 = 0.0f;
+    else {
+        t2 *= t2;
+        n2 = t2 * t2 * grad(perm[ii+i2+perm[jj+j2+perm[kk+k2+perm[ll+l2]]]], x2, y2, z2, w2);
+    }
+
+    double t3 = 0.6f - x3*x3 - y3*y3 - z3*z3 - w3*w3;
+    if(t3 < 0.0f) n3 = 0.0f;
+    else {
+        t3 *= t3;
+        n3 = t3 * t3 * grad(perm[ii+i3+perm[jj+j3+perm[kk+k3+perm[ll+l3]]]], x3, y3, z3, w3);
+    }
+
+    double t4 = 0.6f - x4*x4 - y4*y4 - z4*z4 - w4*w4;
+    if(t4 < 0.0f) n4 = 0.0f;
+    else {
+        t4 *= t4;
+        n4 = t4 * t4 * grad(perm[ii+1+perm[jj+1+perm[kk+1+perm[ll+1]]]], x4, y4, z4, w4);
+    }
+
+    // Sum up and scale the result to cover the range [-1,1]
+    return 27.3f * (n0 + n1 + n2 + n3 + n4); // TODO: The scale factor is preliminary!
+}
+//---------------------------------------------------------------------

src/libraries/noise1234/simplexnoise1234.h

@@ -13,8 +13,7 @@
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // General Public License for more details.
 
-// Modified by the LOVE Development Team to remove 3D and 4D implementations due
-// to patent issues.
+// Modified by the LOVE Development Team to use double precision.
 
 /** \file
 		\brief Declares the SimplexNoise1234 class for producing Perlin simplex noise.
@@ -37,10 +36,13 @@ class SimplexNoise1234 {
  */
     static float noise( double x );
     static float noise( double x, double y );
+    static float noise( double x, double y, double z );
+    static float noise( double x, double y, double z, double w);
 
   private:
     static unsigned char perm[];
     static double  grad( int hash, double x );
     static double  grad( int hash, double x, double y );
-
+    static double  grad( int hash, double x, double y, double z );
+    static double  grad( int hash, double x, double y, double z, double t );
 };