Add DirectionalField to orx-jumpflood

orx-jumpflood/src/main/kotlin/DirectionalField.kt

@@ -0,0 +1,46 @@
+package org.openrndr.extra.jumpfill
+
+import org.openrndr.draw.ColorBuffer
+import org.openrndr.draw.ColorFormat
+import org.openrndr.draw.Filter
+import org.openrndr.draw.colorBuffer
+import org.openrndr.extra.parameters.Description
+import org.openrndr.extra.parameters.DoubleParameter
+import org.openrndr.math.Vector2
+
+@Description("Directional field")
+class DirectionalField : Filter() {
+    @DoubleParameter("threshold", 0.0, 1.0)
+    var threshold = 0.5
+
+    @DoubleParameter("distance scale", 0.0, 1.0)
+    var distanceScale = 1.0
+
+    private val thresholdFilter = Threshold()
+    private var thresholded: ColorBuffer? = null
+    private val contourFilter = ContourPoints()
+    private var contoured: ColorBuffer? = null
+    private var jumpFlooder: JumpFlooder? = null
+
+    private val decodeFilter = PixelDirection()
+
+    override fun apply(source: Array<ColorBuffer>, target: Array<ColorBuffer>) {
+        if (thresholded == null) {
+            thresholded = colorBuffer(target[0].width, target[0].height, format = ColorFormat.R)
+        }
+        if (contoured == null) {
+            contoured = colorBuffer(target[0].width, target[0].height, format = ColorFormat.R)
+        }
+        if (jumpFlooder == null) {
+            jumpFlooder = JumpFlooder(target[0].width, target[0].height)
+        }
+        thresholdFilter.threshold = threshold
+        thresholdFilter.apply(source[0], thresholded!!)
+        contourFilter.apply(thresholded!!, contoured!!)
+        val result = jumpFlooder!!.jumpFlood(contoured!!)
+        decodeFilter.originalSize = Vector2(target[0].width * 1.0, target[0].height * 1.0)
+        decodeFilter.distanceScale = distanceScale
+        decodeFilter.apply(result, result)
+        result.copyTo(target[0])
+    }
+}