Summary of this package.
The plyLoadR htmlwidget aims to provide an alternative to the use of the rgl widget, but only in the cases where such widget does not optimally render graphics.
As an alternative, the three.js library is being used in order to render graphics.
These are some of the cases where the plyLoadR widget is, in the opinion of its creator (me and all my bias), a great alternative to rgl:
- Display graphics with opacity.
- Render some scene where the geometries for rgl have already been created, but the rendering of the respective file (Rmd, for example) takes too long to finish or perhaps never concludes.
- Non trivial JavaScript manipulation of the graphics rendered is required.
For lightweight graphics, the rgl package works fine when displaying semi or fully transparent geometries. However, whenever the geometry displayed is complex/heavy enough, the rgl graphics turn out laggy.
The plyLoadR solution consists in, first, using rgl to save the geometries required into ply files; and, then, loading such ply files with the plyLoadR widget.
That way, there is no lag due to semi or fully transparent graphics.
Due to the inability of the rgl package to load ply objects into the final graphic, such geometries have to be created every time its respective file (Rmd, for example) gets rendered. However, such rendering process may take too long, even when using the cache chunk property, due to Pandoc's conversion of the markdown file into HTML.
Like the previous solution, the plyLoadR approach requires the conversion of rgl geometries into ply files. Then, the plyLoadR widget loads such ply files into the final HTML, without the need of rerunning the rgl code for such geometries' creation, nor of embedding such geometries into the markdown file which Pandoc will convert.
In some cases, such solution has reduced the rendering time of graphics previously displayed via rgl, from 5 minutes, to 10 seconds.
The rgl widget does provide JavaScript methods for modifying the rgl graphic inserted into a HTML. However, the official documentation for those methods is quite poor.
Besides this, the use of three.js when rendering graphics via plyLoadR provides many more tools for adding custom interactivity to the graphic, via appropriate JavaScript use.