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[R-pkg-devel] Help request for rgl update

2 messages · Duncan Murdoch, James Owen Ramsay, Dr.

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Summary:

I'm in the process of a major update to the rgl package and am 
requesting two kinds of help:

- that users of rgl or packages depending on it could report problems 
(and wishlist items).

- that experts in setting up complex packages like rgl could help me to 
rewrite the configuration files.

The new version is available in the "shaders" branch of
https://github.com/dmurdoch/rgl, and for now depends on the small 
package https://github.com/dmurdoch/rasterText/.


Details:

rgl is an old package to do 3D graphics, written by Daniel Adler and 
myself with contributions from a large number of people.  It has a few 
hundred reverse dependencies.

The planned update replaces the code from OpenGL 1.2 (released in 1998) 
with more modern code.  Currently I am targeting OpenGL 3.3 Core Profile 
from 2010, as that seems to be the most widely available version 
nowadays that is backward compatible with newer versions.

The main benefit of the update is to allow the use of "shaders" within 
R.  These are programs written in the GLSL language to allow fine 
control of rendering that isn't possible in the (obsolete) "fixed 
pipeline" used previously.  One application I hope to be able to 
implement soon is the ability to show cross-sections of the interior of 
3D solids such as are shown in CT scans.

Because I have replaced essentially all the rendering code to make this 
update, it's very likely that I've missed some features and introduced 
some new bugs.  Testing by existing users will help me to track down and 
fix those issues.

I've also rewritten all the text-handling code.  Previously there were 
several different schemes for drawing text, and I'm hoping that nowadays 
a single one (based on PangoCairo) will work on all platforms.  The 
problem here is that this brings in a complicated set of system 
dependencies, and I really need help to get the configuration right.

In the current version of the update, this depends on a small package 
https://github.com/dmurdoch/rasterText/. I intend to bring that code 
into the main rgl package before release, but first I'd like to get it 
to pass checks on all platforms, and I really don't know what I'm doing 
with configuration files.

If anyone can help me in either of these ways, I'd really appreciate it.

Duncan Murdoch
2 days later
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Hi Duncan,

How great to hear from you. The lack of which is due to much neglect of the McGill side of my two inboxes.

But I?m still fiddling with another version of TestGardener, where we found rgl to be really helpful.

Here?s my favorite problem:

I construct a 3D curve with in very high manifold.  I do this with eigenanalysis of course.  It turns out that almost all of the variation is within 2 or 3 dimensions.  Percentages like 98.8% for example.  Hence a chance to see the curve can be very illuminating with in the testing context.  The 3D version would also benefit much by being able to view it from many viewpoints and by being able to move it smoothly.

At first I was able to use plotly for this purpose, this no works in R.

Any suggestions?  I?d sure like to get back to using rgl.

Maureen and I have moved into a seniors? residence in Ottawa and we find it actually very pleasant.  I?m fine but she is having more and more severe memory issues.  Nevertheless, I still love to tinker.

I?d love to hear from you about things other than rgl, such as Duncan himself and his family.

Jim. Ramsay