Question

我正在尝试在JavaScript中创建一个perlin / simplex / value噪声函数，它会产生类似于以下结果：

enter image description here （注意：此图像已经应用了阈值。我希望它没有阈值。）

我现在已经在互联网上看了2天了。有很多链接可以解释噪声和很多代码，但JavaScript中没有，每当我尝试转换它时，我都会得到奇怪的结果。以下是我的一些尝试：

http://jsfiddle.net/GZCye/
http://jsfiddle.net/Lk56f/（based on this）
http://pastebin.com/nMA40SrL（由于某种原因，不会在小提琴中运行，based on this

我认为部分问题可能源于在JavaScript中使用按位运算符，因为很难强制执行数字类型。

我正在寻找的是一个工作的例子，JavaScript噪音（无论什么类型）。

我也愿意为有关参数的任何信息提供奖励，这些信息可能导致类似于我发布的图像（阈值之前）或任何优化提示的模式，因为我需要这样快速运行尽可能（在JavaScript中）。

Answer 1

我曾经做过类似的事，但是我使用了中点位移。如果你能弄明白最新情况可能会有所帮助，

http://www.somethinghitme.com/projects/canvasterrain/

它也在这里

https://github.com/loktar00/Javascript-Canvas-Terrain-Generator

这里只是用一些很酷的灯光实现的噪音部分，

http://jsfiddle.net/loktar/4qAxZ/

祝你好运:)。

Answer 2

我将使用this Gist.

上的代码

Answer 3

我知道这已经很老了，但也许它对其他人来说仍然有用。我已经构建了一个将Perlin和Simplex噪音渲染到HTML5画布的javascript应用程序，请在此处查看：http://lencinhaus.github.com/canvas-noise

该应用程序允许调整噪声计算和渲染中涉及的每个参数，并保存生成的纹理。它还将参数添加到URL，以便可以共享它。例如，this configuration生成的纹理与您展示的纹理非常相似。

希望有所帮助！

Answer 4

以下是我最终得到的2D / 3D Perlin噪声代码。请注意，它使用RequireJS的AMD模块语法，但如果您不使用AMD加载程序，则可以将其删除。

define(
    [],
    function()
    {
        function fade(t)
        {
            return t * t * t * (t * (t * 6 - 15) + 10);
        }

        function lerp(t, a, b)
        {
            return a + t * (b - a);
        }

        function grad(hash, x, y, z)
        {
            // Convert lo 4 bits of hash code into 12 gradient directions.
            var h = hash & 15,
                u = h < 8 ? x : y,
                v = h < 4 ? y : h == 12 || h == 14 ? x : z;
            return ((h & 1) == 0 ? u : -u) + ((h & 2) == 0 ? v : -v);
        }

        function scale(n)
        {
            return (1 + n) / 2;
        }

        var p = new Array(512);

        var permutation = [
            151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140, 36, 103, 30, 69, 142, 8, 99,
            37, 240, 21, 10, 23, 190, 6, 148, 247, 120, 234, 75, 0, 26, 197, 62, 94, 252, 219, 203, 117, 35, 11, 32,
            57, 177, 33, 88, 237, 149, 56, 87, 174, 20, 125, 136, 171, 168, 68, 175, 74, 165, 71, 134, 139, 48, 27, 166,
            77, 146, 158, 231, 83, 111, 229, 122, 60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143,
            54, 65, 25, 63, 161, 1, 216, 80, 73, 209, 76, 132, 187, 208, 89, 18, 169, 200, 196, 135, 130, 116, 188, 159,
            86, 164, 100, 109, 198, 173, 186, 3, 64, 52, 217, 226, 250, 124, 123, 5, 202, 38, 147, 118, 126, 255, 82,
            85, 212, 207, 206, 59, 227, 47, 16, 58, 17, 182, 189, 28, 42, 223, 183, 170, 213, 119, 248, 152, 2, 44,
            154, 163, 70, 221, 153, 101, 155, 167, 43, 172, 9, 129, 22, 39, 253, 19, 98, 108, 110, 79, 113, 224, 232,
            178, 185, 112, 104, 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241, 81, 51,
            145, 235, 249, 14, 239, 107, 49, 192, 214, 31, 181, 199, 106, 157, 184, 84, 204, 176, 115, 121, 50, 45,
            127, 4, 150, 254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 243, 141, 128, 195, 78, 66, 215, 61, 156, 180
        ];

        for (var i = 0; i < 256; i++) {
            p[256 + i] = p[i] = permutation[i];
        }

        return {
            /** Returns a number between 0 and 1. */
            noise3d: function(x, y, z)
            {
                // Find unit cube that contains point.
                var X = Math.floor(x) & 255,
                    Y = Math.floor(y) & 255,
                    Z = Math.floor(z) & 255;
                // Find relative x,y,z of point in cube.
                x -= Math.floor(x);
                y -= Math.floor(y);
                z -= Math.floor(z);
                // Compute fade curves for each of x,y,z.
                var u = fade(x),
                    v = fade(y),
                    w = fade(z);
                // Hash coordinates of the corners.
                var A = p[X    ] + Y, AA = p[A] + Z, AB = p[A + 1] + Z,
                    B = p[X + 1] + Y, BA = p[B] + Z, BB = p[B + 1] + Z;

                // Add blended results from 8 corners of cube.
                return scale(
                    lerp(
                        w,
                        lerp(
                            v,
                            lerp(
                                u,
                                grad(p[AA], x, y, z),
                                grad(p[BA], x - 1, y, z)
                            ),
                            lerp(
                                u,
                                grad(p[AB], x, y - 1, z),
                                grad(p[BB], x - 1, y - 1, z)
                            )
                        ),
                        lerp(
                            v,
                            lerp(
                                u,
                                grad(p[AA + 1], x, y, z - 1),
                                grad(p[BA + 1], x - 1, y, z - 1)
                            ),
                            lerp(
                                u,
                                grad(p[AB + 1], x, y - 1, z - 1),
                                grad(p[BB + 1], x - 1, y - 1, z - 1)
                            )
                        )
                    )
                );
            },

            /** Returns a number between 0 and 1. */
            noise2d: function(x, y)
            {
                // Find unit square that contains point.
                var X = Math.floor(x) & 255,
                    Y = Math.floor(y) & 255;
                // Find relative x,y of point in square.
                x -= Math.floor(x);
                y -= Math.floor(y);
                // Compute fade curves for each of x,y.
                var u = fade(x),
                    v = fade(y);
                // Hash coordinates of the corners.
                var A = p[X    ] + Y, AA = p[A], AB = p[A + 1],
                    B = p[X + 1] + Y, BA = p[B], BB = p[B + 1];

                // Add blended results from the corners.
                return scale(
                    lerp(
                        v,
                        lerp(
                            u,
                            grad(p[AA], x, y, 0),
                            grad(p[BA], x - 1, y, 0)
                        ),
                        lerp(
                            u,
                            grad(p[AB], x, y - 1, 0),
                            grad(p[BB], x - 1, y - 1, 0)
                        )
                    )
                );
            }
        };
    }
);

Answer 5

我想出了这个解决方案，可以为我的用例提供更好的结果：

http://asserttrue.blogspot.com/2011/12/perlin-noise-in-javascript_31.html

它使用一个大排列矩阵：

var permutation = [ 151,160,137,91,90,15,
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
];

用作：

pn = PerlinNoise()
n = pn.noise( random_x, random_y, .8 )

JavaScript simplex / perlin噪音

5 个答案: