row and column

src/main/kotlin/com/neptuneclient/voidui/widgets/Column.kt

@@ -0,0 +1,38 @@
+package com.neptuneclient.voidui.widgets
+
+import com.neptuneclient.voidui.framework.*
+import kotlin.math.max
+
+/**
+ * A group widget which lets you place widgets in a cloumn.
+ *
+ * @param children The widgets in the row.
+ * @param gap The gap between the widgets.
+ */
+class Column(private val children: Array<Widget>, private val gap: Float = 0f) : GroupWidget() {
+
+    override fun layout(constraints: BoxConstraints) {
+        var w = 0f
+        var h = gap * (children.size - 1)
+        children.forEach {
+            it.layout(constraints)
+            w = max(h, it.size.width)
+            h += it.size.height
+        }
+        size = constraints.constrain(Size(w, h))
+    }
+
+    override fun postLayoutInit(parentOffset: Offset, parent: Widget) {
+        var y = parentOffset.y
+        children.forEach {
+            it.postLayoutInit(Offset(parentOffset.x, y), this)
+            y += it.size.height + gap
+        }
+        offset = parentOffset
+    }
+
+    override fun buildGroup(): Array<Widget> {
+        return children
+    }
+
+}

src/main/kotlin/com/neptuneclient/voidui/widgets/Row.kt

@@ -0,0 +1,38 @@
+package com.neptuneclient.voidui.widgets
+
+import com.neptuneclient.voidui.framework.*
+import kotlin.math.max
+
+/**
+ * A group widget which lets you place widgets in a row.
+ *
+ * @param children The widgets in the row.
+ * @param gap The gap between the widgets.
+ */
+class Row(private val children: Array<Widget>, private val gap: Float = 0f) : GroupWidget() {
+
+    override fun layout(constraints: BoxConstraints) {
+        var w = gap * (children.size - 1)
+        var h = 0f
+        children.forEach {
+            it.layout(constraints)
+            w += it.size.width
+            h = max(h, it.size.height)
+        }
+        size = constraints.constrain(Size(w, h))
+    }
+
+    override fun postLayoutInit(parentOffset: Offset, parent: Widget) {
+        var x = parentOffset.x
+        children.forEach {
+            it.postLayoutInit(Offset(x, parentOffset.y), this)
+            x += it.size.width + gap
+        }
+        offset = parentOffset
+    }
+
+    override fun buildGroup(): Array<Widget> {
+        return children
+    }
+
+}

src/test/kotlin/com/neptuneclient/voidui/tests/ScreenTest.kt

@@ -24,7 +24,8 @@ class TestScreen(voidUI: VoidUI) : Screen(voidUI) {
             border = Border(2f, Color.RED),
             height = 600f,
 
-            child = Stack(
+            child = Column(
+                gap = 20f,
                 children = arrayOf(
                     Image(
                         src = image("images/hampter.png"),