Add a Perturb filter to orx-fx

orx-fx/src/main/kotlin/distort/Perturb.kt

@@ -0,0 +1,72 @@
+package org.openrndr.extra.fx.distort
+
+import org.openrndr.draw.*
+import org.openrndr.extra.fx.filterFragmentCode
+import org.openrndr.extra.parameters.Description
+import org.openrndr.extra.parameters.DoubleParameter
+import org.openrndr.extra.parameters.IntParameter
+import org.openrndr.math.Vector3
+import org.openrndr.math.Vector4
+
+@Description("Perturb")
+class Perturb : Filter(Shader.createFromCode(filterVertexCode, filterFragmentCode("distort/perturb.frag"))) {
+    var seed: Vector3 by parameters
+
+    /**
+     * base noise scale, default is Vector3(1.0, 1.0, 1.0)
+     */
+    @DoubleParameter("scale", 0.01, 8.0)
+    var scale: Double by parameters
+
+    @DoubleParameter("phase", -2.0, 2.0)
+    var phase: Double by parameters
+
+    /**
+     * lacunarity is the amount by which scale is modulated per octave, default is Vector3(2.0, 2.0, 2.0)
+     */
+    @DoubleParameter("lacunarity", 0.0, 1.0)
+    var lacunarity: Double by parameters
+
+    @DoubleParameter("gain", 0.0, 1.0)
+    var gain: Double by parameters
+
+    @DoubleParameter("decay", 0.0, 1.0)
+    var decay: Double by parameters
+
+    /**
+     * the number of octaves of noise to generate, default is 4
+     */
+    @IntParameter("octaves", 1, 10)
+    var octaves: Int by parameters
+
+
+    @IntParameter("x segments", 0, 256)
+    var xSegments: Int by parameters
+
+    @IntParameter("y segments", 0, 256)
+    var ySegments: Int by parameters
+
+
+
+    init {
+        seed = Vector3.ZERO
+        scale = 1.0
+        lacunarity = 2.0
+        gain = 0.5
+        decay = 0.5
+        octaves = 4
+        phase = 0.0
+        xSegments = 0
+        ySegments = 0
+
+    }
+    var bicubicFiltering = true
+    override fun apply(source: Array<ColorBuffer>, target: Array<ColorBuffer>) {
+        if (bicubicFiltering && source.isNotEmpty()) {
+            source[0].generateMipmaps()
+            source[0].filter(MinifyingFilter.LINEAR_MIPMAP_LINEAR, MagnifyingFilter.LINEAR)
+        }
+        super.apply(source, target)
+    }
+
+}

orx-fx/src/main/resources/org/openrndr/extra/fx/gl3/distort/perturb.frag

@@ -0,0 +1,170 @@
+#version 330
+
+// uniforms
+uniform float gain;
+uniform vec3 seed;
+uniform float phase;
+uniform float scale;
+
+uniform float lacunarity;
+uniform float decay;
+
+uniform int octaves;
+uniform sampler2D tex0;
+
+uniform int xSegments;
+uniform int ySegments;
+
+// varyings
+in vec2 v_texCoord0;
+
+// outputs
+out vec4 o_output;
+
+// Simplex Noise 3D Implementation
+// Description : Array and textureless GLSL 2D/3D/4D simplex
+//               noise functions.
+//      Author : Ian McEwan, Ashima Arts.
+//  Maintainer : ijm
+//     Lastmod : 20110822 (ijm)
+//     License : Copyright (C) 2011 Ashima Arts. All rights reserved.
+//               Distributed under the MIT License. See LICENSE file.
+//               https://github.com/ashima/webgl-noise
+//               https://github.com/stegu/webgl-noise
+//
+//
+vec3 mod289(vec3 x) {
+    return x - floor(x * (1.0 / 289.0)) * 289.0;
+}
+
+vec4 mod289(vec4 x) {
+    return x - floor(x * (1.0 / 289.0)) * 289.0;
+}
+
+vec4 permute(vec4 x) {
+    return mod289(((x*34.0)+1.0)*x);
+}
+
+vec4 taylorInvSqrt(vec4 r)
+{
+    return 1.79284291400159 - 0.85373472095314 * r;
+}
+
+float snoise(vec3 v)
+{
+    const vec2  C = vec2(1.0/6.0, 1.0/3.0) ;
+    const vec4  D = vec4(0.0, 0.5, 1.0, 2.0);
+
+    // First corner
+    vec3 i  = floor(v + dot(v, C.yyy) );
+    vec3 x0 =   v - i + dot(i, C.xxx) ;
+
+    // Other corners
+    vec3 g = step(x0.yzx, x0.xyz);
+    vec3 l = 1.0 - g;
+    vec3 i1 = min( g.xyz, l.zxy );
+    vec3 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;
+    vec3 x1 = x0 - i1 + C.xxx;
+    vec3 x2 = x0 - i2 + C.yyy; // 2.0*C.x = 1/3 = C.y
+    vec3 x3 = x0 - D.yyy;      // -1.0+3.0*C.x = -0.5 = -D.y
+
+    // Permutations
+    i = mod289(i);
+    vec4 p = permute( permute( permute(
+    i.z + vec4(0.0, i1.z, i2.z, 1.0 ))
+    + i.y + vec4(0.0, i1.y, i2.y, 1.0 ))
+    + i.x + vec4(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)
+    float n_ = 0.142857142857; // 1.0/7.0
+    vec3  ns = n_ * D.wyz - D.xzx;
+
+    vec4 j = p - 49.0 * floor(p * ns.z * ns.z);  //  mod(p,7*7)
+
+    vec4 x_ = floor(j * ns.z);
+    vec4 y_ = floor(j - 7.0 * x_ );    // mod(j,N)
+
+    vec4 x = x_ *ns.x + ns.yyyy;
+    vec4 y = y_ *ns.x + ns.yyyy;
+    vec4 h = 1.0 - abs(x) - abs(y);
+
+    vec4 b0 = vec4( x.xy, y.xy );
+    vec4 b1 = vec4( 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;
+    vec4 s0 = floor(b0)*2.0 + 1.0;
+    vec4 s1 = floor(b1)*2.0 + 1.0;
+    vec4 sh = -step(h, vec4(0.0));
+
+    vec4 a0 = b0.xzyw + s0.xzyw*sh.xxyy ;
+    vec4 a1 = b1.xzyw + s1.xzyw*sh.zzww ;
+
+    vec3 p0 = vec3(a0.xy,h.x);
+    vec3 p1 = vec3(a0.zw,h.y);
+    vec3 p2 = vec3(a1.xy,h.z);
+    vec3 p3 = vec3(a1.zw,h.w);
+
+    //Normalise gradients
+    vec4 norm = taylorInvSqrt(vec4(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(0.6 - vec4(dot(x0,x0), dot(x1,x1), dot(x2,x2), dot(x3,x3)), 0.0);
+    m = m * m;
+    return 42.0 * dot( m*m, vec4( dot(p0,x0), dot(p1,x1),
+    dot(p2,x2), dot(p3,x3) ) );
+}
+
+vec3 segment(vec3 t, int x, int y) {
+
+    float sx = x == 0? t.x : floor(t.x * x) / x;
+    float sy = y == 0? t.y : floor(t.y * y) / y;
+
+    return vec3(sx,sy, t.z);
+}
+
+void main() {
+    float tx = 0.0;
+    float ty = 0.0;
+
+    float _gain = gain;
+    float shift = 100.0;
+
+    vec3 xseed = vec3(seed.xy, seed.z+cos(phase*3.1415926535));
+    vec3 yseed = vec3(seed.yx, seed.z+sin(phase*3.1415926535));
+
+    vec3 uv = vec3(v_texCoord0, 1.0) * 2.0 - 1.0;
+    vec3 px = ((segment(uv, xSegments, ySegments) + xseed) * scale);
+    vec3 py = ((segment(uv, xSegments, ySegments) + yseed + vec3(100.37, 40.51, 9.43)) * scale);
+
+    for (int o = 0; o < octaves; ++o) {
+        tx += snoise(px) * _gain;
+        ty += snoise(py) * _gain;
+        px = px * lacunarity + shift;
+        py = py * lacunarity + shift;
+        _gain *= decay;
+    }
+
+    vec2 distCoord = v_texCoord0 + vec2(tx, ty);
+
+    if (distCoord.x >= 0.0 && distCoord.y >= 0.0 && distCoord.x < 1.0 && distCoord.y < 1.0) {
+
+        if (xSegments == 0 && ySegments == 0) {
+            o_output = texture(tex0, distCoord);
+        } else {
+            o_output = textureLod(tex0, distCoord, 0.0);
+        }
+    } else {
+        o_output = vec4(0.0);
+    }
+}