diff --git a/src/main/java/de/bixilon/minosoft/gui/rendering/world/view/WorldVisibilityGraph.kt b/src/main/java/de/bixilon/minosoft/gui/rendering/world/view/WorldVisibilityGraph.kt
index 406fc9643..057d6780d 100644
--- a/src/main/java/de/bixilon/minosoft/gui/rendering/world/view/WorldVisibilityGraph.kt
+++ b/src/main/java/de/bixilon/minosoft/gui/rendering/world/view/WorldVisibilityGraph.kt
@@ -21,6 +21,7 @@ import de.bixilon.minosoft.data.registries.AABB
 import de.bixilon.minosoft.data.world.OcclusionUpdateCallback
 import de.bixilon.minosoft.data.world.chunk.Chunk
 import de.bixilon.minosoft.data.world.chunk.ChunkNeighbours
+import de.bixilon.minosoft.data.world.positions.InChunkSectionPosition
 import de.bixilon.minosoft.gui.rendering.RenderConstants
 import de.bixilon.minosoft.gui.rendering.RenderWindow
 import de.bixilon.minosoft.gui.rendering.camera.Camera
@@ -140,7 +141,7 @@ class WorldVisibilityGraph(
         return frustum.containsAABB(aabb)
     }
 
-    fun isSectionVisible(chunkPosition: Vec2i, sectionHeight: Int, minPosition: Vec3i = DEFAULT_MIN_POSITION, maxPosition: Vec3i = ProtocolDefinition.CHUNK_SECTION_SIZE, checkChunk: Boolean = true): Boolean {
+    fun isSectionVisible(chunkPosition: Vec2i, sectionHeight: Int, minPosition: InChunkSectionPosition = DEFAULT_MIN_POSITION, maxPosition: InChunkSectionPosition = ProtocolDefinition.CHUNK_SECTION_SIZE, checkChunk: Boolean = true): Boolean {
         if (checkChunk && !isChunkVisible(chunkPosition)) {
             return false
         }
diff --git a/src/main/java/de/bixilon/minosoft/util/KUtil.kt b/src/main/java/de/bixilon/minosoft/util/KUtil.kt
index 1570609e9..06f4e51db 100644
--- a/src/main/java/de/bixilon/minosoft/util/KUtil.kt
+++ b/src/main/java/de/bixilon/minosoft/util/KUtil.kt
@@ -66,7 +66,7 @@ object KUtil {
         return when (this) {
             is String -> ResourceLocation(this)
             is ResourceLocation -> this
-            else -> TODO("Don't know how to turn $this into a resource location!")
+            else -> throw IllegalArgumentException("Don't know how to turn $this into a resource location!")
         }
     }
 
@@ -217,6 +217,17 @@ object KUtil {
         return null
     }
 
+    private inline fun String.checkInt(): Int? {
+        var first = true
+        for (point in codePoints()) {
+            if (point < '0'.code || point > '9'.code || (first && point == '-'.code)) {
+                return null
+            }
+            first = false
+        }
+        return this.toInt()
+    }
+
     fun Any?.autoType(): Any? {
         if (this == null) {
             return null
@@ -233,10 +244,7 @@ object KUtil {
             return false
         }
 
-        // ToDo: Optimize
-        if (string.matches("\\d+".toRegex())) {
-            return string.toInt()
-        }
+        string.checkInt()?.let { return it }
 
         return string
     }