Giuseppe Bilotta<p>And of course if possible you want to let the user choose arbitrary inter-particle spacings, possibly at runtime. This is e.g. the reason why <a href="https://fediscience.org/tags/GPUSPH" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>GPUSPH</span></a> has a built-in simple <a href="https://fediscience.org/tags/CSG" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>CSG</span></a> (<a href="https://fediscience.org/tags/ConstructiveSolidGeometry" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>ConstructiveSolidGeometry</span></a>) system: it's not needed for <a href="https://fediscience.org/tags/SPH" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>SPH</span></a>, but it allows user to set up test cases even with relatively complex geometries without resorting to external preprocessing stages that wouldn't give the same flexibility in term of resolution choices.</p><p>And here's the thing: the CSG in GPUSPH has a *lot* of room for improvement, but it's not really the “core” of GPUSPH: how much developer time should be dedicated to it, especially considering that the number of developers is small, and most have more competences in the mathematical and physical aspects of SPH rather than in CSG?</p><p>The end result is that things get implemented “as needed”, which brings me back to the gamedev thread I was mentioning earlier:</p><p>3/</p>