adamjenkins / moodle-local_scribbles

v0.1.1 2026-11-04 06:55 UTC

Requires

• moodle/composer-installer: ^1.0
• moodle/moodle: >=5.2 <5.4

GPL-3.0-or-later

• Adam Jenkins

Published on Packagist.org on 2026-11-04 09:49 UTC

README

A Moodle local plugin that lets teachers draw on any Moodle page and take a screenshot of it. A button opens a transparent drawing layer over the page, with a toolbar of drawing tools. Annotations stay editable after they are drawn and can be saved as an annotation page to open again later. A screenshot can be downloaded or saved to the teacher's "My scribbles" page.

Features

• Button next to the edit mode switch, or a link in the footer help (?) menu, or both (Site administration → Plugins → Local plugins → Scribbles).
• Tools: select, pen, highlighter, text, box, ellipse and eraser (which removes each annotation it touches). Six preset colours and a custom colour picker, a size slider, undo (Ctrl/Cmd+Z) and clear all (which undo also reverses). Hold Shift with box or ellipse to draw a square or a circle. The last tool, colour and size are remembered in the browser (localStorage) from page to page.
• Edit annotations with the select tool: click one to select it, drag it to move it, drag a corner to resize it, or pick a colour to recolour it. Click it again to swap the corner handles for rotate handles. Delete removes it. Hold Shift to keep proportions when resizing or to rotate in 15 degree steps. Undo covers all of this.
• Annotation pages save the annotations themselves, separately from screenshots. The toolbar's annotation pages button names and saves the current annotations, and lists saved pages to open on the current Moodle page. My scribbles lists them too, and Open there goes back to the Moodle page they were drawn on. Annotations stay where they were on the screen, so they line up best in a window of the same size. Opening one is undoable. Saving an opened page updates it, or Save as new makes a copy. Saved pages can be deleted from the same list or from My scribbles; screenshots are deleted from My scribbles.
• Screenshots of the visible page with the annotations on it:
  • Download saves a PNG to the computer.
  • Save stores it on the server in the user's own file area. My scribbles (/local/scribbles/index.php) lists saved screenshots with the page they were taken on, and lets the user download or delete them.
• The X button appears exactly where the navigation bar button that opens scribbles is, so the same spot turns it on and off. If that button is not on the page (footer link only), the X is in the top right corner. Escape also closes scribbles, after first closing the pages panel or clearing a selection.

How screenshots are taken

Screenshots use the browser's own screen capture (navigator.mediaDevices.getDisplayMedia), which asks for the current tab. The browser asks the user once, at the first screenshot after scribbles is opened, to allow sharing of the tab, and the capture stops when scribbles is closed. Browsers allow screen capture only on HTTPS sites. On a plain HTTP site you can draw, but screenshots are not available. The image shows exactly what was on screen, whatever the theme or CSS. No third-party library is used. Chrome and Edge suggest the current tab. In Firefox and Safari the user picks it from a list.

While scribbles is open the page cannot be scrolled, because the drawing is pinned to the visible part of the page.

Who can use it

The capability local/scribbles:use (course level) is given to the editingteacher, teacher and manager archetypes. Inside a course or activity it is checked there. On pages outside courses (Dashboard, profile, front page, admin pages), anyone who holds it in at least one course can use scribbles. Users can always see and delete what they saved, even after they lose the capability.

The capability carries RISK_PERSONAL: a screenshot shows whatever was on the screen, so one of a gradebook, say, stores students' personal data in the teacher's own area, where only that teacher can see it.

Each user may keep 100 screenshots and 100 annotation pages by default. Change the limits, or set 0 for none, at Site administration → Plugins → Local plugins → Scribbles.

Requirements

• Moodle 5.2 (2026042000) or later.
• A browser with getDisplayMedia for screenshots. Drawing works in every modern browser.

Installation

1. Copy this plugin into local/scribbles in your Moodle codebase.
2. Visit Site administration → Notifications to install it.
3. Optionally, choose where the button appears at Site administration → Plugins → Local plugins → Scribbles.

Privacy

Saved screenshots and annotation pages, with the URL and title of the page each was made on, are personal data of the user who saved them. They are kept in that user's context. The privacy provider exports and deletes them. They are also deleted when the user is deleted. A saved page URL never keeps its sesskey.

License

2026 Adam Jenkins [e-mail]

GNU GPL v3 or later. See LICENSE.