[Chalkboard] Percentage units for the aspect ratio do not work

[jwarz]

The chalkboard using percentage units does not work. Only absolute values for the aspect ratio can be supplied. Is there a workaround to fit the chalkboard to different resolutions?

Working Example:

Reveal.initialize({

  width: 960,
  height: 700,

  margin: 0.04,

  minScale: 0.2,
  maxScale: 2.0

  chalkboard: {
			        src: "plugin/chalkboard/chalkboard.json",
		        }

});

Non working Example:

Reveal.initialize({

  width: 100%,
  height: 100%,

  margin: 0.04,

  minScale: 0.2,
  maxScale: 2.0

  chalkboard: {
			        src: "plugin/chalkboard/chalkboard.json",
		        }

});

[pfisterer]

I have a similar issue. However, I do not specify any width/height explicitly but I am using reveal's default settings. The chalkboard used to work with a previous version but with the recent one, it stopped working correctly and the coordinates seem to be wrong. I've recorded a short screencast to demonstrate the issue:

[rajgoel]

@pfisterer Thanks for the screencast. Does the demo work correctly for you? If yes, do you have a clue what's different? If no, can you provide information on browser, os, etc so that I might reproduce the issue?

[pfisterer]

@rajgoel Thanks for looking into it. Your demo does actually work. A non-working example is available here. I've tested using the latest Chrome and Firefox on macOS. I'm dumping the settings passed to Reveal.initialize using console.log.

[rajgoel]

@pfisterer Your issue is probably not related to this thread. Please let us continue the discussion at #124 .

[rajgoel]

Regarding the original issue of this thread, the reason is probably that the chalkboard plugin must know the aspect ratio for proper scaling for playback and broadcast with different screen sizes. A percentage width & height do not provide this information, absolute values do. As soon as there is clarity of whether this is the actual reason or whether there is a reasonable workaround, the documentation should be updated accordingly.