Helper to generate previews of reources or files. This object is used to generate previews for resources of files. Create an own, custom preview generator. Check if the resource changed, if so it will be invalidated and the corresponding signal emitted. Queue a resource being edited for preview (using an instance). Once the preview is ready, your receiver.receiver_func will be called either containing the preview texture or an empty texure (if no preview was possible). Callback must have the format: (path,texture,userdata). Userdata can be anything. Queue a resource file for preview (using a path). Once the preview is ready, your receiver.receiver_func will be called either containing the preview texture or an empty texure (if no preview was possible). Callback must have the format: (path,texture,userdata). Userdata can be anything. Remove a custom preview generator. If a preview was invalidated (changed) this signal will emit (using the path of the preview)