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)
+    }
+
+}