Fix error when removing items from a VoxelInstanceLibrary

Author: Zylann

doc/source/changelog.md

@@ -33,6 +33,7 @@ Primarily developped with Godot 4.3.
         - Fixed slow loading when the database path contains `res://` or `user://`
         - Fixed crash if the database has an invalid path and `flush()` is called after `set_key_cache_enabled(true)`
     - `VoxelInstancer`: Fixed instances with LOD > 0 were generated on `VoxelTerrain` even though LOD isn't supported (ending up in weird positions). No instances should generate.
+    - `VoxelInstanceLibrary`: Fixed `Assertion failed: "p_id < 0 || p_id >= MAX_ID" is false` when removing items from a VoxelInstanceLibrary
     - `VoxelMeshSDF`: Fixed error in the editor when trying to visualize the last slice (which turns out to be off by 1)
     - `VoxelModifierMesh`: 
         - Fixed setting `isolevel` had no effect

terrain/instancing/voxel_instance_library.cpp

@@ -51,7 +51,7 @@ void VoxelInstanceLibrary::add_item(int p_id, Ref<VoxelInstanceLibraryItem> item
 }
 
 void VoxelInstanceLibrary::remove_item(int p_id) {
-	ZN_ASSERT_RETURN(p_id < 0 || p_id >= MAX_ID);
+	ZN_ASSERT_RETURN(p_id >= 0 && p_id < MAX_ID);
 	const unsigned int id = p_id;
 	auto it = _items.find(id);
 	ERR_FAIL_COND_MSG(it == _items.end(), "Cannot remove unregistered item");