# PDF Pointer Control

The **PDF Pointer Control** app (`app/pdf-pointer-c`) is the phone and tablet controller for the **PDF Pointer Display** app (`app/pdf-pointer`). Together they show a local PDF on a shared screen with a remote controlled pointer.

![PDF Pointer Control App Icon](pwa-512x512.png "PDF Pointer Control App Icon")

## Overview

This app lets a phone, tablet, or desktop browser choose a local PDF file and send it to a `pdf-pointer` display in the same RCWeb room. After the display loads the document, the controller provides simple vertical scrolling and a touch pad for moving the pointer over the PDF.

The control app is designed for touch use. The main actions are large: **Select PDF**, **Scroll Up**, **Scroll Down**, and the pointer touch area.

## How to use

1. Open `/pdf-pointer/` on the main display.
2. Scan the QR code shown by the display.
3. Press **Select PDF** and choose a PDF from this device.
4. Keep this controller open while the display loads the document.
5. Use the up and down scroll buttons to move through the PDF.
6. Drag inside the touch pad to move the pointer on the display.

## Controls

- **Select PDF** chooses a local `.pdf` file and shares it with the display.
- **Scroll Up** moves the displayed PDF upward.
- **Scroll Down** moves the displayed PDF downward.
- **Hide QR** or **Show QR** toggles the display's bottom-right QR code panel.
- The touch pad acts like a relative trackpad for the pointer overlay.

## PDF transfer

The selected PDF stays on the controller device and is streamed to the display through RCWeb's `/x-file/` proxy. It is not uploaded as a permanent server file.

Do not close or refresh the controller while the display is loading the PDF. Closing the controller stops the active file stream and can leave the display without the full document.

## Multiple controllers

Several controllers can be open in the same room, but the PDF file is hosted by the controller that selected it. If that controller is closed, other controllers can still send pointer and scroll commands, but the display may not be able to reload missing PDF data.

## Related app

Use this app with **PDF Pointer Display** (`app/pdf-pointer`).