Tried to fetch a resource, but the resource does not exist.
This is the most common issue you will face as a new user of Specs.
This panic will occur whenever a
System is first dispatched, and one or
more of the components and/or resources it uses is missing from
There are a few main reasons for this occurring:
- Forgetting to call
setupafter building a
ParSeq. Make sure this is always run before the first dispatch.
- Not adding mandatory resources to
World. You can usually find these by searching for occurrences of
- Manually requesting components/resources from
World(not inside a
System), where the component/resource is not used by any
Systems, which is most common when using the
EntityBuilder. This is an artifact of how
setupworks, it will only add what is found inside the used
Systems. If you use other components/resources, you need to manually register/add these to