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Jason

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This is EPIC!

 

 

Hmmm - 'Info Wars' looks like Fox news...This is nothing new, try:

 

Amusing Ourselves to Death: Public Discourse in the Age of Show Business (1985) by Neil Postman.

https://en.wikipedia.org/wiki/Amusing_Ourselves_to_Death

 

Brave New World is a novel written in 1931 by Aldous Huxley and published in 1932

https://en.wikipedia.org/wiki/Brave_New_World

Edited by tar
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Calculating exact Oriented Bounding Boxes - complete with C++ code.

 

http://clb.demon.fi/minobb/minobb_jylanki_2015_06_01.pdf

 

This paper and some other fast OBB algorithms use the convex hull of the input geometry. The one in Houdini and Bullet's convex hull generators are far from optimal, and implementing a fast, robust convex hull is a lot harder than OBBs. It would be nice if SESI added one to Houdini that did just that.

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... The one in Houdini and Bullet's convex hull generators are far from optimal...

what are you basing this on?

there seems to have been a lot of work done on that front for H15, but I personally don't know anything about algorithm behind, so just asking

:

Houdini 14.5.2: Added version 2.0 of the Shrinkwrap SOP, which uses the convex hull algorithm that the Bullet solver switched to in Houdini 13. This is significantly faster than the previous version (e.g. computing the convex hull of the squab model is about 20x faster) and simpler geometry is produced when shrinking convex hulls.

Houdini 14.5.28: The Bullet solver is now about 10% faster when computing convex hulls.

Houdini 14.5.35: Improved the performance of setting up convex hull shapes in the Bullet solver by about 20%.

Houdini 14.5.37: Improved the performance of constructing convex hull collision shapes in the Bullet solver by about 75%.

Houdini 14.5.58: Improved the performance and memory usage of the Bullet solver for convex hull shapes, particularly if the geometry only contains a primitive tube, sphere, box, or capsule.

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what are you basing this on?

there seems to have been a lot of work done on that front for H15, but I personally don't know anything about algorithm behind, so just asking

:

Houdini 14.5.2: Added version 2.0 of the Shrinkwrap SOP, which uses the convex hull algorithm that the Bullet solver switched to in Houdini 13. This is significantly faster than the previous version (e.g. computing the convex hull of the squab model is about 20x faster) and simpler geometry is produced when shrinking convex hulls.

Houdini 14.5.28: The Bullet solver is now about 10% faster when computing convex hulls.

Houdini 14.5.35: Improved the performance of setting up convex hull shapes in the Bullet solver by about 20%.

Houdini 14.5.37: Improved the performance of constructing convex hull collision shapes in the Bullet solver by about 75%.

Houdini 14.5.58: Improved the performance and memory usage of the Bullet solver for convex hull shapes, particularly if the geometry only contains a primitive tube, sphere, box, or capsule.

 

AFAIK libraries like qhull is a lot faster than most of the convex hull generators out there, which is a very well known library with lots of years of development. I remember seeing some performance stats comparing it to other computational geometry libraries. I believe only some special parallelized versions or one on the GPU was faster.

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AFAIK libraries like qhull is a lot faster than most of the convex hull generators out there, which is a very well known library with lots of years of development. I remember seeing some performance stats comparing it to other computational geometry libraries. I believe only some special parallelized versions or one on the GPU was faster.

 

 

It's be better to dig up some concrete results as a quick search shows qhull as old, bad license and people want to improve on it:

 

'The qhull implementation has a somewhat questionable license and more significantly it is a really complex piece of software and contains a bunch of other features. I'm on a quest to create a fast, robust convex hull generator that is free to use and is self-contained in a single cpp file.'

 

http://tuxedolabs.blogspot.co.nz/2013/03/convex-hulls-revisited.html

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