Couple world pos fixes/improvements.

src/rpg/world/worldpos.c

@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) 2025 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "worldpos.h"
+
+void chunkPosToWorldPos(const chunkpos_t* chunkPos, worldpos_t* out) {
+  out->x = (worldunit_t)(chunkPos->x * CHUNK_WIDTH);
+  out->y = (worldunit_t)(chunkPos->y * CHUNK_HEIGHT);
+  out->z = (worldunit_t)(chunkPos->z * CHUNK_DEPTH);
+}