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@@ -11,38 +11,33 @@
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* You can pass in a random number generator object if you like.
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* It is assumed to have a random() method.
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*/
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-var SimplexNoise = function( r ) {
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-
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- if ( r == undefined ) r = Math;
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- this.grad3 = [[ 1,1,0 ],[ - 1,1,0 ],[ 1,- 1,0 ],[ - 1,- 1,0 ],
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- [ 1,0,1 ],[ - 1,0,1 ],[ 1,0,- 1 ],[ - 1,0,- 1 ],
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- [ 0,1,1 ],[ 0,- 1,1 ],[ 0,1,- 1 ],[ 0,- 1,- 1 ]];
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-
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- this.grad4 = [[ 0,1,1,1 ], [ 0,1,1,- 1 ], [ 0,1,- 1,1 ], [ 0,1,- 1,- 1 ],
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- [ 0,- 1,1,1 ], [ 0,- 1,1,- 1 ], [ 0,- 1,- 1,1 ], [ 0,- 1,- 1,- 1 ],
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- [ 1,0,1,1 ], [ 1,0,1,- 1 ], [ 1,0,- 1,1 ], [ 1,0,- 1,- 1 ],
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- [ - 1,0,1,1 ], [ - 1,0,1,- 1 ], [ - 1,0,- 1,1 ], [ - 1,0,- 1,- 1 ],
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- [ 1,1,0,1 ], [ 1,1,0,- 1 ], [ 1,- 1,0,1 ], [ 1,- 1,0,- 1 ],
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- [ - 1,1,0,1 ], [ - 1,1,0,- 1 ], [ - 1,- 1,0,1 ], [ - 1,- 1,0,- 1 ],
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- [ 1,1,1,0 ], [ 1,1,- 1,0 ], [ 1,- 1,1,0 ], [ 1,- 1,- 1,0 ],
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- [ - 1,1,1,0 ], [ - 1,1,- 1,0 ], [ - 1,- 1,1,0 ], [ - 1,- 1,- 1,0 ]];
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+var SimplexNoise = function(r) {
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+ if (r == undefined) r = Math;
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+ this.grad3 = [[ 1,1,0 ],[ -1,1,0 ],[ 1,-1,0 ],[ -1,-1,0 ],
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+ [ 1,0,1 ],[ -1,0,1 ],[ 1,0,-1 ],[ -1,0,-1 ],
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+ [ 0,1,1 ],[ 0,-1,1 ],[ 0,1,-1 ],[ 0,-1,-1 ]];
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+
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+ this.grad4 = [[ 0,1,1,1 ], [ 0,1,1,-1 ], [ 0,1,-1,1 ], [ 0,1,-1,-1 ],
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+ [ 0,-1,1,1 ], [ 0,-1,1,-1 ], [ 0,-1,-1,1 ], [ 0,-1,-1,-1 ],
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+ [ 1,0,1,1 ], [ 1,0,1,-1 ], [ 1,0,-1,1 ], [ 1,0,-1,-1 ],
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+ [ -1,0,1,1 ], [ -1,0,1,-1 ], [ -1,0,-1,1 ], [ -1,0,-1,-1 ],
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+ [ 1,1,0,1 ], [ 1,1,0,-1 ], [ 1,-1,0,1 ], [ 1,-1,0,-1 ],
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+ [ -1,1,0,1 ], [ -1,1,0,-1 ], [ -1,-1,0,1 ], [ -1,-1,0,-1 ],
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+ [ 1,1,1,0 ], [ 1,1,-1,0 ], [ 1,-1,1,0 ], [ 1,-1,-1,0 ],
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+ [ -1,1,1,0 ], [ -1,1,-1,0 ], [ -1,-1,1,0 ], [ -1,-1,-1,0 ]];
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this.p = [];
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- for ( var i = 0; i < 256; i ++ ) {
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-
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- this.p[ i ] = Math.floor( r.random() * 256 );
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-
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+ for (var i = 0; i < 256; i ++) {
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+ this.p[i] = Math.floor(r.random() * 256);
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}
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- // To remove the need for index wrapping, double the permutation table length
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+ // To remove the need for index wrapping, double the permutation table length
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this.perm = [];
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- for ( var i = 0; i < 512; i ++ ) {
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-
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- this.perm[ i ] = this.p[ i & 255 ];
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-
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+ for (var i = 0; i < 512; i ++) {
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+ this.perm[i] = this.p[i & 255];
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}
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- // A lookup table to traverse the simplex around a given point in 4D.
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- // Details can be found where this table is used, in the 4D noise method.
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+ // A lookup table to traverse the simplex around a given point in 4D.
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+ // Details can be found where this table is used, in the 4D noise method.
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this.simplex = [
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[ 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 ],
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[ 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 ],
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@@ -52,163 +47,111 @@ var SimplexNoise = function( r ) {
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[ 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 ],
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[ 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 ],
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[ 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 ]];
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-
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};
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-SimplexNoise.prototype.dot = function( g, x, y ) {
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-
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- return g[ 0 ] * x + g[ 1 ] * y;
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-
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+SimplexNoise.prototype.dot = function(g, x, y) {
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+ return g[0] * x + g[1] * y;
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};
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-SimplexNoise.prototype.dot3 = function( g, x, y, z ) {
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-
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- return g[ 0 ] * x + g[ 1 ] * y + g[ 2 ] * z;
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-
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+SimplexNoise.prototype.dot3 = function(g, x, y, z) {
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+ return g[0] * x + g[1] * y + g[2] * z;
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};
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-SimplexNoise.prototype.dot4 = function( g, x, y, z, w ) {
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-
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- return g[ 0 ] * x + g[ 1 ] * y + g[ 2 ] * z + g[ 3 ] * w;
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-
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+SimplexNoise.prototype.dot4 = function(g, x, y, z, w) {
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+ return g[0] * x + g[1] * y + g[2] * z + g[3] * w;
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};
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-SimplexNoise.prototype.noise = function( xin, yin ) {
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-
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+SimplexNoise.prototype.noise = function(xin, yin) {
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var n0, n1, n2; // Noise contributions from the three corners
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- // Skew the input space to determine which simplex cell we're in
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- var F2 = 0.5 * ( Math.sqrt( 3.0 ) - 1.0 );
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- var s = ( xin + yin ) * F2; // Hairy factor for 2D
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- var i = Math.floor( xin + s );
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- var j = Math.floor( yin + s );
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- var G2 = ( 3.0 - Math.sqrt( 3.0 ) ) / 6.0;
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- var t = ( i + j ) * G2;
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+ // Skew the input space to determine which simplex cell we're in
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+ var F2 = 0.5 * (Math.sqrt(3.0) - 1.0);
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+ var s = (xin + yin) * F2; // Hairy factor for 2D
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+ var i = Math.floor(xin + s);
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+ var j = Math.floor(yin + s);
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+ var G2 = (3.0 - Math.sqrt(3.0)) / 6.0;
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+ var t = (i + j) * G2;
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var X0 = i - t; // Unskew the cell origin back to (x,y) space
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var Y0 = j - t;
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var x0 = xin - X0; // The x,y distances from the cell origin
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var y0 = yin - Y0;
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- // For the 2D case, the simplex shape is an equilateral triangle.
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- // Determine which simplex we are in.
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+ // For the 2D case, the simplex shape is an equilateral triangle.
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+ // Determine which simplex we are in.
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var i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords
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- if ( x0 > y0 ) {
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-
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- i1 = 1; j1 = 0;
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-
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- } // lower triangle, XY order: (0,0)->(1,0)->(1,1)
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- else {
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-
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- i1 = 0; j1 = 1;
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-
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- } // upper triangle, YX order: (0,0)->(0,1)->(1,1)
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- // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
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- // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
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- // c = (3-sqrt(3))/6
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+ if (x0 > y0) {i1 = 1; j1 = 0;} // lower triangle, XY order: (0,0)->(1,0)->(1,1)
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+ else {i1 = 0; j1 = 1;} // upper triangle, YX order: (0,0)->(0,1)->(1,1)
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+ // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
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+ // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
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+ // c = (3-sqrt(3))/6
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var x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords
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var y1 = y0 - j1 + G2;
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var x2 = x0 - 1.0 + 2.0 * G2; // Offsets for last corner in (x,y) unskewed coords
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var y2 = y0 - 1.0 + 2.0 * G2;
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- // Work out the hashed gradient indices of the three simplex corners
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+ // Work out the hashed gradient indices of the three simplex corners
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var ii = i & 255;
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var jj = j & 255;
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- var gi0 = this.perm[ ii + this.perm[ jj ]] % 12;
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- var gi1 = this.perm[ ii + i1 + this.perm[ jj + j1 ]] % 12;
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- var gi2 = this.perm[ ii + 1 + this.perm[ jj + 1 ]] % 12;
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- // Calculate the contribution from the three corners
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+ var gi0 = this.perm[ii + this.perm[jj]] % 12;
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+ var gi1 = this.perm[ii + i1 + this.perm[jj + j1]] % 12;
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+ var gi2 = this.perm[ii + 1 + this.perm[jj + 1]] % 12;
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+ // Calculate the contribution from the three corners
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var t0 = 0.5 - x0 * x0 - y0 * y0;
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- if ( t0 < 0 ) n0 = 0.0;
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+ if (t0 < 0) n0 = 0.0;
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else {
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-
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t0 *= t0;
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- n0 = t0 * t0 * this.dot( this.grad3[ gi0 ], x0, y0 ); // (x,y) of grad3 used for 2D gradient
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-
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+ n0 = t0 * t0 * this.dot(this.grad3[gi0], x0, y0); // (x,y) of grad3 used for 2D gradient
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}
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var t1 = 0.5 - x1 * x1 - y1 * y1;
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- if ( t1 < 0 ) n1 = 0.0;
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+ if (t1 < 0) n1 = 0.0;
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else {
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-
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t1 *= t1;
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- n1 = t1 * t1 * this.dot( this.grad3[ gi1 ], x1, y1 );
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-
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+ n1 = t1 * t1 * this.dot(this.grad3[gi1], x1, y1);
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}
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var t2 = 0.5 - x2 * x2 - y2 * y2;
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- if ( t2 < 0 ) n2 = 0.0;
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+ if (t2 < 0) n2 = 0.0;
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else {
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-
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t2 *= t2;
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- n2 = t2 * t2 * this.dot( this.grad3[ gi2 ], x2, y2 );
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-
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+ n2 = t2 * t2 * this.dot(this.grad3[gi2], x2, y2);
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}
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- // Add contributions from each corner to get the final noise value.
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- // The result is scaled to return values in the interval [-1,1].
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- return 70.0 * ( n0 + n1 + n2 );
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-
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+ // Add contributions from each corner to get the final noise value.
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+ // The result is scaled to return values in the interval [-1,1].
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+ return 70.0 * (n0 + n1 + n2);
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};
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// 3D simplex noise
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-SimplexNoise.prototype.noise3d = function( xin, yin, zin ) {
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-
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+SimplexNoise.prototype.noise3d = function(xin, yin, zin) {
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var n0, n1, n2, n3; // Noise contributions from the four corners
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- // Skew the input space to determine which simplex cell we're in
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+ // Skew the input space to determine which simplex cell we're in
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var F3 = 1.0 / 3.0;
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- var s = ( xin + yin + zin ) * F3; // Very nice and simple skew factor for 3D
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- var i = Math.floor( xin + s );
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- var j = Math.floor( yin + s );
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- var k = Math.floor( zin + s );
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+ var s = (xin + yin + zin) * F3; // Very nice and simple skew factor for 3D
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+ var i = Math.floor(xin + s);
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+ var j = Math.floor(yin + s);
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+ var k = Math.floor(zin + s);
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var G3 = 1.0 / 6.0; // Very nice and simple unskew factor, too
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- var t = ( i + j + k ) * G3;
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+ var t = (i + j + k) * G3;
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var X0 = i - t; // Unskew the cell origin back to (x,y,z) space
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var Y0 = j - t;
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var Z0 = k - t;
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var x0 = xin - X0; // The x,y,z distances from the cell origin
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var y0 = yin - Y0;
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var z0 = zin - Z0;
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- // For the 3D case, the simplex shape is a slightly irregular tetrahedron.
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- // Determine which simplex we are in.
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+ // For the 3D case, the simplex shape is a slightly irregular tetrahedron.
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+ // Determine which simplex we are in.
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var i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords
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var i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords
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- if ( x0 >= y0 ) {
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-
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- if ( y0 >= z0 ) {
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-
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- i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0;
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-
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- } // X Y Z order
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- else if ( x0 >= z0 ) {
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-
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- i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1;
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-
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- } // X Z Y order
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- else {
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-
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- i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1;
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-
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- } // Z X Y order
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-
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+ if (x0 >= y0) {
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+ if (y0 >= z0)
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+ { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // X Y Z order
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+ else if (x0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1; } // X Z Y order
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+ else { i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1; } // Z X Y order
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}
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- else {
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-
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- // x0<y0
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- if ( y0 < z0 ) {
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-
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- i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1;
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-
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- } // Z Y X order
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- else if ( x0 < z0 ) {
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-
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- i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1;
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-
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- } // Y Z X order
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- else {
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-
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- i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0;
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-
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- } // Y X Z order
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-
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+ else { // x0<y0
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+ if (y0 < z0) { i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1; } // Z Y X order
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+ else if (x0 < z0) { i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1; } // Y Z X order
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+ else { i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // Y X Z order
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}
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- // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z),
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- // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and
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- // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where
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- // c = 1/6.
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+ // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z),
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+ // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and
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+ // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where
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+ // c = 1/6.
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var x1 = x0 - i1 + G3; // Offsets for second corner in (x,y,z) coords
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var y1 = y0 - j1 + G3;
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var z1 = z0 - k1 + G3;
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@@ -218,72 +161,62 @@ SimplexNoise.prototype.noise3d = function( xin, yin, zin ) {
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var x3 = x0 - 1.0 + 3.0 * G3; // Offsets for last corner in (x,y,z) coords
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var y3 = y0 - 1.0 + 3.0 * G3;
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var z3 = z0 - 1.0 + 3.0 * G3;
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- // Work out the hashed gradient indices of the four simplex corners
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+ // Work out the hashed gradient indices of the four simplex corners
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var ii = i & 255;
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var jj = j & 255;
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var kk = k & 255;
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- var gi0 = this.perm[ ii + this.perm[ jj + this.perm[ kk ]]] % 12;
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- var gi1 = this.perm[ ii + i1 + this.perm[ jj + j1 + this.perm[ kk + k1 ]]] % 12;
|
|
|
- var gi2 = this.perm[ ii + i2 + this.perm[ jj + j2 + this.perm[ kk + k2 ]]] % 12;
|
|
|
- var gi3 = this.perm[ ii + 1 + this.perm[ jj + 1 + this.perm[ kk + 1 ]]] % 12;
|
|
|
- // Calculate the contribution from the four corners
|
|
|
+ var gi0 = this.perm[ii + this.perm[jj + this.perm[kk]]] % 12;
|
|
|
+ var gi1 = this.perm[ii + i1 + this.perm[jj + j1 + this.perm[kk + k1]]] % 12;
|
|
|
+ var gi2 = this.perm[ii + i2 + this.perm[jj + j2 + this.perm[kk + k2]]] % 12;
|
|
|
+ var gi3 = this.perm[ii + 1 + this.perm[jj + 1 + this.perm[kk + 1]]] % 12;
|
|
|
+ // Calculate the contribution from the four corners
|
|
|
var t0 = 0.6 - x0 * x0 - y0 * y0 - z0 * z0;
|
|
|
- if ( t0 < 0 ) n0 = 0.0;
|
|
|
+ if (t0 < 0) n0 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t0 *= t0;
|
|
|
- n0 = t0 * t0 * this.dot3( this.grad3[ gi0 ], x0, y0, z0 );
|
|
|
-
|
|
|
+ n0 = t0 * t0 * this.dot3(this.grad3[gi0], x0, y0, z0);
|
|
|
}
|
|
|
var t1 = 0.6 - x1 * x1 - y1 * y1 - z1 * z1;
|
|
|
- if ( t1 < 0 ) n1 = 0.0;
|
|
|
+ if (t1 < 0) n1 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t1 *= t1;
|
|
|
- n1 = t1 * t1 * this.dot3( this.grad3[ gi1 ], x1, y1, z1 );
|
|
|
-
|
|
|
+ n1 = t1 * t1 * this.dot3(this.grad3[gi1], x1, y1, z1);
|
|
|
}
|
|
|
var t2 = 0.6 - x2 * x2 - y2 * y2 - z2 * z2;
|
|
|
- if ( t2 < 0 ) n2 = 0.0;
|
|
|
+ if (t2 < 0) n2 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t2 *= t2;
|
|
|
- n2 = t2 * t2 * this.dot3( this.grad3[ gi2 ], x2, y2, z2 );
|
|
|
-
|
|
|
+ n2 = t2 * t2 * this.dot3(this.grad3[gi2], x2, y2, z2);
|
|
|
}
|
|
|
var t3 = 0.6 - x3 * x3 - y3 * y3 - z3 * z3;
|
|
|
- if ( t3 < 0 ) n3 = 0.0;
|
|
|
+ if (t3 < 0) n3 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t3 *= t3;
|
|
|
- n3 = t3 * t3 * this.dot3( this.grad3[ gi3 ], x3, y3, z3 );
|
|
|
-
|
|
|
+ n3 = t3 * t3 * this.dot3(this.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 );
|
|
|
-
|
|
|
+ // 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);
|
|
|
};
|
|
|
|
|
|
// 4D simplex noise
|
|
|
SimplexNoise.prototype.noise4d = function( x, y, z, w ) {
|
|
|
-
|
|
|
// For faster and easier lookups
|
|
|
var grad4 = this.grad4;
|
|
|
var simplex = this.simplex;
|
|
|
var perm = this.perm;
|
|
|
|
|
|
- // The skewing and unskewing factors are hairy again for the 4D case
|
|
|
- var F4 = ( Math.sqrt( 5.0 ) - 1.0 ) / 4.0;
|
|
|
- var G4 = ( 5.0 - Math.sqrt( 5.0 ) ) / 20.0;
|
|
|
+ // The skewing and unskewing factors are hairy again for the 4D case
|
|
|
+ var F4 = (Math.sqrt(5.0) - 1.0) / 4.0;
|
|
|
+ var G4 = (5.0 - Math.sqrt(5.0)) / 20.0;
|
|
|
var 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
|
|
|
- var s = ( x + y + z + w ) * F4; // Factor for 4D skewing
|
|
|
- var i = Math.floor( x + s );
|
|
|
- var j = Math.floor( y + s );
|
|
|
- var k = Math.floor( z + s );
|
|
|
- var l = Math.floor( w + s );
|
|
|
- var t = ( i + j + k + l ) * G4; // Factor for 4D unskewing
|
|
|
+ // Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in
|
|
|
+ var s = (x + y + z + w) * F4; // Factor for 4D skewing
|
|
|
+ var i = Math.floor(x + s);
|
|
|
+ var j = Math.floor(y + s);
|
|
|
+ var k = Math.floor(z + s);
|
|
|
+ var l = Math.floor(w + s);
|
|
|
+ var t = (i + j + k + l) * G4; // Factor for 4D unskewing
|
|
|
var X0 = i - t; // Unskew the cell origin back to (x,y,z,w) space
|
|
|
var Y0 = j - t;
|
|
|
var Z0 = k - t;
|
|
@@ -293,43 +226,43 @@ SimplexNoise.prototype.noise4d = function( x, y, z, w ) {
|
|
|
var z0 = z - Z0;
|
|
|
var 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.
|
|
|
- var c1 = ( x0 > y0 ) ? 32 : 0;
|
|
|
- var c2 = ( x0 > z0 ) ? 16 : 0;
|
|
|
- var c3 = ( y0 > z0 ) ? 8 : 0;
|
|
|
- var c4 = ( x0 > w0 ) ? 4 : 0;
|
|
|
- var c5 = ( y0 > w0 ) ? 2 : 0;
|
|
|
- var c6 = ( z0 > w0 ) ? 1 : 0;
|
|
|
+ // 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.
|
|
|
+ var c1 = (x0 > y0) ? 32 : 0;
|
|
|
+ var c2 = (x0 > z0) ? 16 : 0;
|
|
|
+ var c3 = (y0 > z0) ? 8 : 0;
|
|
|
+ var c4 = (x0 > w0) ? 4 : 0;
|
|
|
+ var c5 = (y0 > w0) ? 2 : 0;
|
|
|
+ var c6 = (z0 > w0) ? 1 : 0;
|
|
|
var c = c1 + c2 + c3 + c4 + c5 + c6;
|
|
|
var i1, j1, k1, l1; // The integer offsets for the second simplex corner
|
|
|
var i2, j2, k2, l2; // The integer offsets for the third simplex corner
|
|
|
var 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.
|
|
|
+ // 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.
|
|
|
var x1 = x0 - i1 + G4; // Offsets for second corner in (x,y,z,w) coords
|
|
|
var y1 = y0 - j1 + G4;
|
|
|
var z1 = z0 - k1 + G4;
|
|
@@ -346,57 +279,46 @@ SimplexNoise.prototype.noise4d = function( x, y, z, w ) {
|
|
|
var y4 = y0 - 1.0 + 4.0 * G4;
|
|
|
var z4 = z0 - 1.0 + 4.0 * G4;
|
|
|
var w4 = w0 - 1.0 + 4.0 * G4;
|
|
|
- // Work out the hashed gradient indices of the five simplex corners
|
|
|
+ // Work out the hashed gradient indices of the five simplex corners
|
|
|
var ii = i & 255;
|
|
|
var jj = j & 255;
|
|
|
var kk = k & 255;
|
|
|
var ll = l & 255;
|
|
|
- var gi0 = perm[ ii + perm[ jj + perm[ kk + perm[ ll ]]]] % 32;
|
|
|
- var gi1 = perm[ ii + i1 + perm[ jj + j1 + perm[ kk + k1 + perm[ ll + l1 ]]]] % 32;
|
|
|
- var gi2 = perm[ ii + i2 + perm[ jj + j2 + perm[ kk + k2 + perm[ ll + l2 ]]]] % 32;
|
|
|
- var gi3 = perm[ ii + i3 + perm[ jj + j3 + perm[ kk + k3 + perm[ ll + l3 ]]]] % 32;
|
|
|
- var gi4 = perm[ ii + 1 + perm[ jj + 1 + perm[ kk + 1 + perm[ ll + 1 ]]]] % 32;
|
|
|
- // Calculate the contribution from the five corners
|
|
|
+ var gi0 = perm[ii + perm[jj + perm[kk + perm[ll]]]] % 32;
|
|
|
+ var gi1 = perm[ii + i1 + perm[jj + j1 + perm[kk + k1 + perm[ll + l1]]]] % 32;
|
|
|
+ var gi2 = perm[ii + i2 + perm[jj + j2 + perm[kk + k2 + perm[ll + l2]]]] % 32;
|
|
|
+ var gi3 = perm[ii + i3 + perm[jj + j3 + perm[kk + k3 + perm[ll + l3]]]] % 32;
|
|
|
+ var gi4 = perm[ii + 1 + perm[jj + 1 + perm[kk + 1 + perm[ll + 1]]]] % 32;
|
|
|
+ // Calculate the contribution from the five corners
|
|
|
var t0 = 0.6 - x0 * x0 - y0 * y0 - z0 * z0 - w0 * w0;
|
|
|
- if ( t0 < 0 ) n0 = 0.0;
|
|
|
+ if (t0 < 0) n0 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t0 *= t0;
|
|
|
- n0 = t0 * t0 * this.dot4( grad4[ gi0 ], x0, y0, z0, w0 );
|
|
|
-
|
|
|
+ n0 = t0 * t0 * this.dot4(grad4[gi0], x0, y0, z0, w0);
|
|
|
}
|
|
|
var t1 = 0.6 - x1 * x1 - y1 * y1 - z1 * z1 - w1 * w1;
|
|
|
- if ( t1 < 0 ) n1 = 0.0;
|
|
|
+ if (t1 < 0) n1 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t1 *= t1;
|
|
|
- n1 = t1 * t1 * this.dot4( grad4[ gi1 ], x1, y1, z1, w1 );
|
|
|
-
|
|
|
+ n1 = t1 * t1 * this.dot4(grad4[gi1], x1, y1, z1, w1);
|
|
|
}
|
|
|
var t2 = 0.6 - x2 * x2 - y2 * y2 - z2 * z2 - w2 * w2;
|
|
|
- if ( t2 < 0 ) n2 = 0.0;
|
|
|
+ if (t2 < 0) n2 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t2 *= t2;
|
|
|
- n2 = t2 * t2 * this.dot4( grad4[ gi2 ], x2, y2, z2, w2 );
|
|
|
-
|
|
|
+ n2 = t2 * t2 * this.dot4(grad4[gi2], x2, y2, z2, w2);
|
|
|
} var t3 = 0.6 - x3 * x3 - y3 * y3 - z3 * z3 - w3 * w3;
|
|
|
- if ( t3 < 0 ) n3 = 0.0;
|
|
|
+ if (t3 < 0) n3 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t3 *= t3;
|
|
|
- n3 = t3 * t3 * this.dot4( grad4[ gi3 ], x3, y3, z3, w3 );
|
|
|
-
|
|
|
+ n3 = t3 * t3 * this.dot4(grad4[gi3], x3, y3, z3, w3);
|
|
|
}
|
|
|
var t4 = 0.6 - x4 * x4 - y4 * y4 - z4 * z4 - w4 * w4;
|
|
|
- if ( t4 < 0 ) n4 = 0.0;
|
|
|
+ if (t4 < 0) n4 = 0.0;
|
|
|
else {
|
|
|
-
|
|
|
t4 *= t4;
|
|
|
- n4 = t4 * t4 * this.dot4( grad4[ gi4 ], x4, y4, z4, w4 );
|
|
|
-
|
|
|
+ n4 = t4 * t4 * this.dot4(grad4[gi4], x4, y4, z4, w4);
|
|
|
}
|
|
|
- // Sum up and scale the result to cover the range [-1,1]
|
|
|
- return 27.0 * ( n0 + n1 + n2 + n3 + n4 );
|
|
|
-
|
|
|
+ // Sum up and scale the result to cover the range [-1,1]
|
|
|
+ return 27.0 * (n0 + n1 + n2 + n3 + n4);
|
|
|
};
|