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digitalmars.D - Feedback: using D in production for 3D products

reply Guillaume Lathoud <gsub glat.info> writes:
Hello,

Here is some feedback from using D, vibe.d, and small parts of 
arsd
to write micro-services to feed 3D products at my company 
[1][2][3].

Overall great: expressive code, fun and reliable development
(esp. using CTFE), excellent runtime performance (critical for 
3D),
and last but not least, very helpful community.

I put further below a few critics, mostly details where something
could be improved, from my point of view.

Most of our code is closed-source, so for now I can only 
contribute
a short, disparate collection of tools [4]. I hope to be able at
some point of time to contribute more, in whatever form that may 
be.

Thanks and best regards,
Guillaume Lathoud

.

Where I'd see room for improvement:

(a) When beginning coding, esp. when using rdmd, it was not 
obvious
to me how to get a meaningful stacktrace. For example, when I open
the rdmd page [5], I have to go down to the options, open the link
to the dmd page [6], then scroll down and search through the 
options
until I find the -g* ones. Probably obvious to seasoned users, but
not necessarily to beginners. A mention on the rdmd page could 
help.

(b) Line numbers in errors in string mixins: two line numbers are
given corresponding to the beginning line and the actual error 
line,
which is already quite helpful. Often I also need the difference
between the two numbers, to find the corresponding line of the 
mixin
source code. That would be a great addition, at least for me.

(c) I don't need to reproduce here the usual rant about the 
current
compilation speed of a few particular libraries like std.regex, 
when
used. Ironically, I found that cost a lot smaller than
catastrophical slowdowns of the compilation due to my very own 
abuse
of the CTFE, which was a bit humbling... and now corrected.

In my experience (a) (b) (c) really are small details, compared to
the positive sides of using D.

[1] 3D video in summer: 
https://www.youtube.com/watch?v=R2aZHKa-iuY
[2] 3D video in winter: 
https://www.youtube.com/watch?v=qIpnH_NSfS8
[3] Company's main website: https://www.outdooractive.com
[4] https://github.com/glathoud/d_glat
[5] https://dlang.org/rdmd.html
[6] https://dlang.org/dmd-linux.html
Mar 27 2019
next sibling parent reply Andre Pany <andre s-e-a-p.de> writes:
On Thursday, 28 March 2019 at 06:36:11 UTC, Guillaume Lathoud 
wrote:

 Hello,

 Here is some feedback from using D, vibe.d, and small parts of 
 arsd
 to write micro-services to feed 3D products at my company 
 [1][2][3].

 [...]


Thanks a lot for this insights and your contributions. For me it 
would be interesting to hear whether there are any reasons to not 
use Dub. (The debug option is on by default here).

Kind regards
Andre
Mar 28 2019
parent Guillaume Lathoud <gsub glat.info> writes:
On Thursday, 28 March 2019 at 11:11:05 UTC, Andre Pany wrote:

 [...]


 Thanks a lot for this insights and your contributions. For me 
 it would be interesting to hear whether there are any reasons 
 to not use Dub. (The debug option is on by default here).

 Kind regards
 Andre


You're welcome. I forgot to mention that, yes, we've been using 
dub in the production projects. To summarize:
  * when doing the very first steps to learn the language, with 
rdmd, it is not obvious that flags have to be added to get a 
better stacktrace on errors. It plays also a role when using rdmd 
to run unit tests and debug them if they fail.
  * when doing the very first steps using Dub, it was not obvious 
to me that -debug is the default.

Of course, once these two facts are known, the issues disappears 
- but having just a few helping comments about this, even just 
one sentence, targeted to beginners, might help others.

Best regards,
Guillaume
Mar 28 2019
prev sibling next sibling parent reply Matheus <m gmail.com> writes:
On Thursday, 28 March 2019 at 06:36:11 UTC, Guillaume Lathoud 
wrote:

 ...
 Here is some feedback from using D, vibe.d, and small parts of 
 arsd
 to write micro-services to feed 3D products at my company...


It's nice to see some stories/feedback for D code in production. 
I usually write some tools in D to help with my work, where the 



 Overall great: expressive code, fun and reliable development
 (esp. using CTFE), excellent runtime performance (critical for 
 3D)...


Could you elaborate about this 3D part? Because in many cases you 
fetch the data and GPU will handle the rendering etc. So I don't 
think the language itself should be a bottleneck.

Matheus.
Mar 28 2019
parent Guillaume Lathoud <gsub glat.info> writes:
On Thursday, 28 March 2019 at 14:38:46 UTC, Matheus wrote:

 Could you elaborate about this 3D part? Because in many cases 
 you fetch the data and GPU will handle the rendering etc. So I 
 don't think the language itself should be a bottleneck.


The original data was a rectangular raster of elevation values, 
which had to be smartly reduced to a few triangles wherever 
available, and accompanied with some meta-data, both parts highly 
useful for the final device to render motion in a 3D world in a 
performant manner. Otherwise, simply feeding the raster to the 
final device led to a barely acceptable user experience.

Since this precomputation should run in any part of the world, D 
was critical to quickly compute the reduced-and-expanded vector 
data over the whole world down to an acceptable level AND be able 
to quickly compute the rest on-demand. In short: performance!

I chose D because I had already had impressive experiences in 
terms of performance in the past.

Best regards,
Guillaume
Mar 28 2019
prev sibling parent reply destructionator gmail.com writes:
On Thu, Mar 28, 2019 at 06:36:11AM +0000, Guillaume Lathoud via Digitalmars-d
wrote:

 and small parts of arsd


What parts did you use? (We probably talked before, but I don't remember
right now.)
Mar 28 2019
parent Guillaume Lathoud <gsub glat.info> writes:
On Thursday, 28 March 2019 at 14:43:37 UTC, destructionator wrote:

 On Thu, Mar 28, 2019 at 06:36:11AM +0000, Guillaume Lathoud via 
 Digitalmars-d wrote:

 and small parts of arsd


 What parts did you use? (We probably talked before, but I don't 
 remember
 right now.)


At the moment we use color.d and png.d to manipulate some 
satellite images. Everything working very fine, thanks for the 
code!

Best regards,
Guillaume
Mar 28 2019