Virtual Scattering Application

Page 8 of 8 Previous  1, 2, 3, 4, 5, 6, 7, 8

Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Sun Aug 11, 2019 6:46 pm

.
Virtual Scattering Application - Page 8 Srcurb10
Proof of life.

Let me clarify, that is, reviewing and cleaning up what I’ve done. Currently reviewing each scene graph, making sure the animations work, making sure that all guns just poke their barrels through the range wall at r=100, etc. Here, the spirals within a given Spiral ring gun are now random, but all the guns are the same; incremental progress sometimes, plenty to do.
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Tue Aug 13, 2019 6:59 pm

.
Virtual Scattering Application - Page 8 Gtypes10
When you changed to Hoso, you indicated that Simple gun was the only gun properly sized. I thought my job was to come up with some acceptable guns. I suppose the only way to correct that situation would be to scale all guns to the Simple gun size. Here are some results. Please feel free to indicate otherwise.

Type (scale.x, scale.y, scale.z) left to right, top to bottom.
Simple, the standard scale ( 1, 1, 1 ); SpiralRing (0.85, 0.85, 0.85 ); Ring ( 0.7, 0.7, 0.7 );
HelixRing ( 0.3, 0.3, 0.3 );  Revolving ( 0.333, 0.333, 0.333 ); Cube ( 0.3, 0.3, 0.3 );

Some additional corrections. On the basis of scale, I'll just toss Simple Array - it's too big.
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Thu Aug 15, 2019 4:23 pm

.
Virtual Scattering Application - Page 8 Gtypes11
Above at left, not shown in the last group due to its extra length, is the Spiral gun, scale (1,1,1). Given the current hoso configuration, as with Simple gun and all the others, adjacent Spiral guns are overlapping a bit at ‘r=the target zone boundary’, I don’t see that as any problem whatsoever.

On the top right, also at scale one, is a recent addition - a barrel topped with two equilateral triangle wings separated by 60 degrees, a tetrahedral dihedral. One can join two such tet-dihedrals together to form a closed tetrahedron. Each side – both inside and outside faces – are of different materials. The more open 2 sided dihedral – as opposed to a closed tetrahedron - shows more interesting motion with minimal obscuration of target scattering. I started by duplicating Simple gun, then swapping out the sphere, bands and endcap with the two tetrahedron faces, - making it simpler than Simple gun. The alternate rotation and pulse color animations work well, including different starting angles and color phase differentials.

Virtual Scattering Application - Page 8 Dihedr10

The idea came from recalling Alexander Graham Bell’s https://en.wikipedia.org/wiki/Tetrahedral_kite tetrahedral kite. In which case I’m obliged to join a minimum of four such dihedrals to see how it looks. I might have tried it by now but for once the paperwork came first. If it’s OK with you I’d like to keep the dihedral version shown. Oh, and work a kite array version separately.
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Fri Aug 16, 2019 5:45 pm

.
Virtual Scattering Application - Page 8 Fourdi10
Today’s four tetrahedron-dihedrals compares closely in position and colors with yesterday’s single tet-dihedral. The single looked good; I think the four array looks better. Don't make me do sixteen. Agreed?
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by Nevyn on Fri Aug 16, 2019 9:28 pm

I think you should get rid of the barrel and just have them shoot out of the point of the pyramid.
Nevyn
Nevyn
Admin

Posts : 1704
Join date : 2014-09-11

View user profile http://www.nevyns-lab.com

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Sat Aug 17, 2019 9:40 pm

.
Virtual Scattering Application - Page 8 Reorie12
Done; the barrel is removed and the dihedrals now 'point' toward the target. Reorienting the dihedrals sounded innocuous enough, doing it turned into a series of challenging problems, the result is worth it, definitely an improvement. I'll scale it down a bit - then cleanup again.
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Mon Aug 19, 2019 12:01 am

.
Virtual Scattering Application - Page 8 Trefoi10
The 4th spin level target b-photon Trefoil knot (?).

I noticed a problem after my last post. The emissions weren’t coming directly from the top of the three sided pyramid - they were a little off, about half a barrel radius off. Specifying the muzzle position didn’t work. It seemed to be a bounding box problem. I went and created the first dihedral’s (triangles 1 and 2) anti-dihedral (triangles 3 and 4). Together they create a closed tetrahedron but together they didn’t correct the problem. I did eventually find and eliminate 3 grp position x y and z settings at line 638 which did fix the emission problem.

Then I noticed the b-photon appears to be a https://en.wikipedia.org/wiki/Trefoil_knot  Trefoil knot. Am I imagining things?
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by Nevyn on Mon Aug 19, 2019 10:44 pm

I have noticed that path, and don't believe I have seen it in any of my other spin apps. I am a bit worried that something is wrong, but most of it looks good.

An AXY spin will look like a trefoil knot. The actual path is not perfect, so it kind of rotates the shape around, over and over. It actually generates a torus, but not by its motion. well, it is by its motion, but it is not a torus type of motion.

However, that path just doesn't look right, but I haven't spent much time looking into it. When I did, I couldn't see anything obvious (and the details are all in matrix math, so hard to see).
Nevyn
Nevyn
Admin

Posts : 1704
Join date : 2014-09-11

View user profile http://www.nevyns-lab.com

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Tue Aug 20, 2019 12:50 am

.
I thought the path was unusual. It would be amazing if knot theory is related to stacked spins.

Virtual Scattering Application - Page 8 Sixtdi10
And of course I'm sure it's no surprise to you that I had to see what the sixteen dihedral array looks like. A Sierpinski triangle https://en.wikipedia.org/wiki/Sierpiński_triangle  comes close.

Can we keep it? Please?
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by Nevyn on Tue Aug 20, 2019 1:22 am

I'm not sure about them. It's the see-through bits that bug me. They look like pyramids, but then you get close and there are sides missing.

At this stage, I don't really know how these guns are going to be used. I imagine some sort of user control to choose them, but haven't put any effort into setting that up. So at this stage, I don't mind having options.
Nevyn
Nevyn
Admin

Posts : 1704
Join date : 2014-09-11

View user profile http://www.nevyns-lab.com

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman on Tue Aug 20, 2019 6:05 pm

.
Virtual Scattering Application - Page 8 Tet16a10
The two-sided dihedrals are now changed to four-sided tetrahedrons.

Less see-through, more solid - done. The dihedrals are now tetrahedrons. I've made a few more corrections getting it into its current form making sure all the faces are covered, so to speak. Unless you suggest otherwise, I’ll also change the name to Tetra Array gun. But please bear witness, with all due respect, Alexander Graham Bell’s basic tetrahedral kite is in the code – just eliminate triangles 3 and 4. Of course any code I write is in initial final, there are many ways it can be better written. Such as with fewer group calls, i.e. coming up with a single ‘this.geometry.tetrahedron’ instead of a separate call for every inside and outside triangle. I'll try to improve it some more before moving on.
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by LongtimeAirman Yesterday at 11:44 pm

.
Virtual Scattering Application - Page 8 Alignt10
Update. I haven’t posted for a few days because I’ve been stymied. I’ve switched away from triangles in order to use new THREE tetrahedron geometry – but I must reorient the default polyhedron properly. That doesn't sound too difficult. This autocad image shows the problem/solution. Rotate the new tet geometry 109 degrees clockwise about a spin axis defined by a line from 0,0,0 to 1,0,1. Unfortunately, this solution doesn’t appear to work on the Tetrix gun itself, it’s quite a bit off. I found a close working approximation, off maybe a degree or two, but I haven’t found a working single rotation set or formula yet. I may try to change the default vertices next - that is, when I figure out how.
.

LongtimeAirman
Admin

Posts : 1331
Join date : 2014-08-10

View user profile

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by Nevyn Today at 1:24 am

The problem may be that the center point of the tetrahedron is in the middle of it. Maybe translate the geometry so that the origin is in a known position of that geometry. You could move the tet down and put the top point at the origin, or you could move it up and put the base at the origin. When you rotate it, the point that is at the origin will not move from it.

I would probably put the top point at the origin and then rotate and translate accordingly.

Another potential problem is how you are doing the rotations and translations. If you are doing those on the Object3D object (most likely a Mesh), then you have to be aware of what order the operations are applied it. Does it rotate and then translate, or does it translate before rotating? Order matters a lot. If in doubt, you can use a Group per operation and then you know that they are applied from the bottom up. That is, the geometry is applied first, then the Object3D operations, then the Group that that Object3D is in, etc, etc.
Nevyn
Nevyn
Admin

Posts : 1704
Join date : 2014-09-11

View user profile http://www.nevyns-lab.com

Back to top Go down

Virtual Scattering Application - Page 8 Empty Re: Virtual Scattering Application

Post by Sponsored content


Sponsored content


Back to top Go down

Page 8 of 8 Previous  1, 2, 3, 4, 5, 6, 7, 8

Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum