Add data binding for orx-gradient-descent

Add 0 check in minimizer

orx-gradient-descent/src/main/kotlin/DataBinding.kt

@@ -0,0 +1,73 @@
+package org.openrndr.extra.gradientdescent
+
+import org.openrndr.math.Vector2
+import org.openrndr.math.Vector3
+import org.openrndr.math.Vector4
+
+/**
+ * converts a model to an array of doubles
+ */
+fun <T : Any> modelToArray(model: T): DoubleArray {
+    val doubles = mutableListOf<Double>()
+    model::class.java.declaredFields.forEach {
+        when {
+            it.type == Double::class.java -> {
+                it.trySetAccessible()
+                doubles.add(it.getDouble(model))
+            }
+            it.type == Vector2::class.java -> {
+                it.trySetAccessible()
+                val v2 = it.get(model) as Vector2
+                doubles.add(v2.x)
+                doubles.add(v2.y)
+            }
+            it.type == Vector3::class.java -> {
+                it.trySetAccessible()
+                val v3 = it.get(model) as Vector3
+                doubles.add(v3.x)
+                doubles.add(v3.y)
+                doubles.add(v3.z)
+            }
+            it.type == Vector4::class.java -> {
+                it.trySetAccessible()
+                val v4 = it.get(model) as Vector4
+                doubles.add(v4.x)
+                doubles.add(v4.y)
+                doubles.add(v4.z)
+                doubles.add(v4.w)
+            }
+        }
+    }
+    return doubles.toDoubleArray()
+}
+
+/**
+ * converts array of doubles to model values
+ */
+fun <T : Any> arrayToModel(data: DoubleArray, model: T) {
+    var index = 0
+    model::class.java.declaredFields.forEach {
+        when {
+            it.type == Double::class.java -> {
+                it.trySetAccessible()
+                it.setDouble(model, data[index])
+                index++
+            }
+            it.type == Vector2::class.java -> {
+                it.trySetAccessible()
+                it.set(model, Vector2(data[index], data[index+1]))
+                index+=2
+            }
+            it.type == Vector3::class.java -> {
+                it.trySetAccessible()
+                it.set(model, Vector3(data[index], data[index+1],data[index+2]))
+                index+=3
+            }
+            it.type == Vector4::class.java -> {
+                it.trySetAccessible()
+                it.set(model, Vector4(data[index], data[index+1],data[index+2],data[index+3]))
+                index+=3
+            }
+        }
+    }
+}