> For the complete documentation index, see [llms.txt](https://docs.lmms.io/developer-guides/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lmms.io/developer-guides/core/instruments-and-effects/processing-in-instruments.md). # Processing in instruments Different types of instruments have different ways of processing notes and audio. #### Note-on event * MIDI-based: Forward a MIDI note on event to the instrument plugin * Non-MIDI-based: Construct a `NotePlayHandle` instance for the new note and add it to `AudioEngine` #### Note-off event * MIDI-based: Forward a MIDI note off event to the instrument plugin * Non-MIDI-based: Call `NotePlayHandle::noteOff()` #### Processing notes in the rendering cycle * MIDI-based: Do nothing as the instrument will take care of them * Non-MIDI based and single-streamed: `playNote()` will process the note, but it won't render audio for the note. Instead, `play()` will render the final audio stream for all notes. * Non-MIDI based and multiple-streamed: `playNote()` will process and render the note --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.lmms.io/developer-guides/core/instruments-and-effects/processing-in-instruments.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.