Add a vclip command

src/main/kotlin/codes/som/hibiscus/commands/CommandRegistry.kt

@@ -5,6 +5,7 @@ import codes.som.hibiscus.api.command.CommandManager
 
 fun allCommandClasses(): Array<() -> Command> = arrayOf(
     ::Reload,
+    ::Vclip,
 )
 
 class CommandRegistry : CommandManager() {

src/main/kotlin/codes/som/hibiscus/commands/Vclip.kt

@@ -0,0 +1,41 @@
+package codes.som.hibiscus.commands
+
+import codes.som.hibiscus.api.command.Command
+import codes.som.hibiscus.player
+import codes.som.hibiscus.world
+
+class Vclip : Command("vclip") {
+    init {
+        branch { y: Double ->
+            player.updatePosition(player.x, player.y + y, player.z)
+        }
+
+        branch("up") {
+            val collisionTests = (2..10).map { n ->
+                world.getBlockCollisions(null, player.boundingBox.offset(0.0, n.toDouble(), 0.0)).all { it.isEmpty }
+            }
+
+            if (collisionTests.all { it }) {
+                player.updatePosition(player.x, player.y + 10, player.z)
+            } else {
+                val n = collisionTests.indexOf(true)
+                if (n != -1)
+                    player.updatePosition(player.x, player.y + n + 2, player.z)
+            }
+        }
+
+        branch("down") {
+            val collisionTests = (2..10).map { n ->
+                world.getBlockCollisions(null, player.boundingBox.offset(0.0, -n.toDouble(), 0.0)).all { it.isEmpty }
+            }
+
+            if (collisionTests.all { it }) {
+                player.updatePosition(player.x, player.y - 10, player.z)
+            } else {
+                val n = collisionTests.indexOf(true)
+                if (n != -1)
+                    player.updatePosition(player.x, player.y - n - 2, player.z)
+            }
+        }
+    }
+}