With this plugin you can add a chalkboard to reveal.js. The plugin provides two possibilities to include handwritten notes to your presentation:
The main use case in mind when implementing the plugin is classroom usage in which you may want to explain some course content and quickly need to make some notes.
The plugin records all drawings made so that they can be play backed using the autoSlide
feature or the audio-slideshow
plugin.
The chalkboard effect is based on Chalkboard by Mohamed Moustafa.
Copy the file plugin.js
and the img
directory into the plugin folder of your reveal.js presentation, i.e. plugin/chalkboard
and load the plugin as shown below.
<script src="plugin/chalkboard/plugin.js"></script>
<script src="plugin/customcontrols/plugin.js"></script>
<script>
Reveal.initialize({
// ...
plugins: [ RevealChalkboard, RevealCustomControls ],
// ...
});
</script>
The following stylesheet
<link rel="stylesheet" href="plugin/chalkboard/style.css">
<link rel="stylesheet" href="plugin/customcontrols/style.css">
has to be included to the head
section of you HTML-file.
In order to include buttons for opening and closing the notes canvas or the chalkboard you should make sure that font-awesome
is available. The easiest way is to include
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
to the head
section of you HTML-file.
If the autoSlide
feature is set or if the audio-slideshow
plugin is used, pre-recorded chalkboard drawings can be played. The slideshow plays back the user interaction with the chalkboard in the same way as it was conducted when recording the data.
The plugin supports multiplexing via the multiplex
plugin or the seminar
plugin.
If the slideshow is opened in print mode, the chalkboard drawings in the session storage (see storage
option - print version must be opened in the same tab or window as the original slideshow) or provided in a file (see src
option) are included in the PDF-file. Each drawing on the chalkboard is added after the slide that was shown when opening the chalkboard. Drawings on the notes canvas are not included in the PDF-file.
The plugin has several configuration options:
boardmarkerWidth
: an integer, the drawing width of the boardmarker; larger values draw thicker lines.chalkWidth
: an integer, the drawing width of the chalk; larger values draw thicker lines.chalkEffect
: a float in the range [0.0, 1.0]
, the intesity of the chalk effect on the chalk board. Full effect (default) 1.0
, no effect 0.0
.storage
: Optional variable name for session storage of drawings.src
: Optional filename for pre-recorded drawings.readOnly
: Configuation option allowing to prevent changes to existing drawings. If set to true
no changes can be made, if set to false false
changes can be made, if unset or set to undefined
no changes to the drawings can be made after returning to a slide or fragment for which drawings had been recorded before. In any case the recorded drawings for a slide or fragment can be cleared by pressing the ‘DEL’ key (i.e. by using the RevealChalkboard.clear()
function).transition
: Gives the duration (in milliseconds) of the transition for a slide change, so that the notes canvas is drawn after the transition is completed.theme
: Can be set to either "chalkboard"
or "whiteboard"
.The following configuration options allow to change the appearance of the notes canvas and the chalkboard. All of these options require two values, the first gives the value for the notes canvas, the second for the chalkboard.
background
: The first value expects a (semi-)transparent color which is used to provide visual feedback that the notes canvas is enabled, the second value expects a filename to a background image for the chalkboard.grid
: By default whiteboard and chalkboard themes include a grid pattern on the background. This pattern can be modified by setting the color, the distance between lines, and the line width, e.g. { color: 'rgb(127,127,255,0.1)', distance: 40, width: 2}
. Alternatively, the grid can be removed by setting the value to false
.eraser
: An image path and radius for the eraser.boardmarkers
: A list of boardmarkers with given color and cursor.chalks
: A list of chalks with given color and cursor.rememberColor
: Whether to remember the last selected color for the slide canvas or the board.All of the configurations are optional and the default values shown below are used if the options are not provided.
Reveal.initialize({
// ...
chalkboard: {
boardmarkerWidth: 3,
chalkWidth: 7,
chalkEffect: 1.0,
storage: null,
src: null,
readOnly: undefined,
transition: 800,
theme: "chalkboard",
background: [ 'rgba(127,127,127,.1)' , path + 'img/blackboard.png' ],
grid: { color: 'rgb(50,50,10,0.5)', distance: 80, width: 2},
eraser: { src: path + 'img/sponge.png', radius: 20},
boardmarkers : [
{ color: 'rgba(100,100,100,1)', cursor: 'url(' + path + 'img/boardmarker-black.png), auto'},
{ color: 'rgba(30,144,255, 1)', cursor: 'url(' + path + 'img/boardmarker-blue.png), auto'},
{ color: 'rgba(220,20,60,1)', cursor: 'url(' + path + 'img/boardmarker-red.png), auto'},
{ color: 'rgba(50,205,50,1)', cursor: 'url(' + path + 'img/boardmarker-green.png), auto'},
{ color: 'rgba(255,140,0,1)', cursor: 'url(' + path + 'img/boardmarker-orange.png), auto'},
{ color: 'rgba(150,0,20150,1)', cursor: 'url(' + path + 'img/boardmarker-purple.png), auto'},
{ color: 'rgba(255,220,0,1)', cursor: 'url(' + path + 'img/boardmarker-yellow.png), auto'}
],
chalks: [
{ color: 'rgba(255,255,255,0.5)', cursor: 'url(' + path + 'img/chalk-white.png), auto'},
{ color: 'rgba(96, 154, 244, 0.5)', cursor: 'url(' + path + 'img/chalk-blue.png), auto'},
{ color: 'rgba(237, 20, 28, 0.5)', cursor: 'url(' + path + 'img/chalk-red.png), auto'},
{ color: 'rgba(20, 237, 28, 0.5)', cursor: 'url(' + path + 'img/chalk-green.png), auto'},
{ color: 'rgba(220, 133, 41, 0.5)', cursor: 'url(' + path + 'img/chalk-orange.png), auto'},
{ color: 'rgba(220,0,220,0.5)', cursor: 'url(' + path + 'img/chalk-purple.png), auto'},
{ color: 'rgba(255,220,0,0.5)', cursor: 'url(' + path + 'img/chalk-yellow.png), auto'}
]
},
customcontrols: {
controls: [
{ icon: '<i class="fa fa-pen-square"></i>',
title: 'Toggle chalkboard (B)',
action: 'RevealChalkboard.toggleChalkboard();'
},
{ icon: '<i class="fa fa-pen"></i>',
title: 'Toggle notes canvas (C)',
action: 'RevealChalkboard.toggleNotesCanvas();'
}
]
},
// ...
});
MIT licensed
Copyright (C) 2021 Asvin Goel