New accretion disk method (WORK IN PROGRESS)

[ElChristou]

...I'll most probably create a new black hole based on accretion disks and jets with sprites.

I was about to ask that!

[Cham]

...I'll most probably create a new black hole based on accretion disks and jets with sprites.

I was about to ask that!

Actually, I now have a pretty long list of models with sprites to create :

1- Accretion disks of various proportions, colors, with turbulence, etc.. (easy)
2- New black holes, (lots of work)
3- Galaxies in interaction (lots of variations possible), from various simulations and time frame, (easy ? Depends on available data)
4- Large scale structures according to various simulations and time frame, (easy ? Depends on available data)
5- Nebulae : cylindrical, spherical with onion style layers, annular and conical parts, etc... (hard)
6- Solar prottuberences (hard)
7- Bridges across stars in binaries (hardest)

This will take months !

[ElChristou]

Would be nice to have a tool to create models only with points...

[Cham]

Would be nice to have a tool to create models only with points...

This could be done in the Terminal app. I'm not an expert in UNIX and awk commands, but I'm sure a shell script could be defined to do some basic rings and sphere models, with and without sprites.

Here are the basic commands I'm using in awk (through the Terminal app) :

Code: Select all

cat path_to_inputdata | awk '{ print $1 "\t" $2 "\t" $3 }' > path_to_putput

cat path_to_input | awk '{ print $1 "\t" $2 "\t" $3 "\t" }' > path_to_output

Some maths can be done in there, like random, sin($1*atan2(0, -1)/180), cos($2*atan2(0, -1)/180), etc... There's a detailed man page in the Terminal (type man awk, for example).

[ElChristou]

Would be nice to have a tool to create models only with points...

This could be done in the Terminal app. I'm not an expert in UNIX and awk commands, but I'm sure a shell script could be defined to do some basic rings and sphere models, with and without sprites.

Here are the basic commands I'm using in awk (through the Terminal app) :

Code: Select all

cat path_to_inputdata | awk '{ print $1 "\t" $2 "\t" $3 }' > path_to_putput

cat path_to_input | awk '{ print $1 "\t" $2 "\t" $3 "\t" }' > path_to_output

Some maths can be done in there, like random, sin($1*atan2(0, -1)/180), cos($2*atan2(0, -1)/180), etc... There's a detailed man page in the Terminal (type man awk, for example).

Go try to modelize with some maths a nice jet for BH...It's why some kind of tool to deal with points in a 3D viewpoint would be great...

[Cham]

My last ring with sprites, combined with an old 3ds planar accretion disk, is already rising up considerably the view :

disk1.jpg

disk2.jpg

And there's a "primitive" spherical shell nebulae around that proto-system. This model isn't perfect, but it's already much better than placing a simple curvy billboard on the background !

nebula.jpg

[ElChristou]

This last accretion disk seems to be VERY nice!

[ANDREA]

Cham, I absolutely agree with Christophe, your last accretion disk is incredibly convincing.
You are doing a very important thing, IMO, please go on this way.
Thanks a lot.
Bye

Andrea

[LordFerret]

That last one is stunning Cham! It reminds me of jll's RCW 79 Nebula addon (Motherload: http://www.celestiamotherlode.net/catalog/show_addon_details.php?addon_id=899) which I always thought was awesome, especially to be flying around in it. I can't wait to see your finished result (hope it will run on my system) !

[ajtribick]

This is looking very good! Beta Pictoris would be a very good system to model with this technique, what with the multiple dust rings, inclined secondary disc, the planet and all.

Is the screenshot with the 3 planets HR 8799?

[Hungry4info]

Wow, this is amazing! I do look forward to seeing these in Celestia myself.

[Cham]

Is the screenshot with the 3 planets HR 8799?

I don't remember, but I think it is.

[Cham]

The combination sprites model + 3ds surface with texture gives some pretty views in Celestia, even if it's not perfect as seen from some point of views. In many cases, it's very satisfying and certainly a great improvement.

Here's one of my old black hole with two sprite rings added to it :

pict1.jpg

pict2.jpg

pict3.jpg

EDIT : Eventually, when the sprites code will be polished and fully functional, I'll get rid of all the 3ds surfaces and the accretion disks should be fully made of sprites.

[BobHegwood]

Absolutely spectacular Martin...
Just had to express my feelings for your work here.

EDIT:
Gonna grab these images for use on my desktop too.

[Cham]

A first jet prototype :

jet1.jpg

Of course, the color can be changed very easily. The jet isn't long enough in this case, but it's just a first model. Could be usefull for volcanoes and water jets on Enceladus, or even comet tails (second tail). The slight curve can be adjusted easily.

Here's the model for you to test (I want some feedback, please, to know if the sprites are working well on your machine. Please, state your video card and OS) :

Sprites_prototype.zip

[ElChristou]

Works ok; not sure for a BH jet but for a plume or comet, why not...

[Cham]

The main problem with this approach, for a jet or a plume, is we wont be able to simulate any motion. Chris is supposed to add an animated sprites code to Celestia, to enable some animation. This should be the right thing for a BH jet, or for a cryo-volcano plume (Enceladus, Triton, ...).

I really don't know how the animated sprites should be declared in an SSC file (velocity, diffusion parameters, acceleration, etc...). Chris, we need more details on this.

[ElChristou]

The main problem with this approach, for a jet or a plume, is we wont be able to simulate any motion. Chris is supposed to add an animated sprites code to Celestia, to enable some animation. This should be the right thing for a BH jet...

I'm not sure animation would fit for BH jets; the speed is so high that you would probably see only a uniform structure... And for the end of the jet we have more some kind of nebulae like structure than something else, so...

[Cham]

I'm not sure animation would fit for BH jets; the speed is so high that you would probably see only a uniform structure... And for the end of the jet we have more some kind of nebulae like structure than something else, so...

The BH jets are extending over a very large distance, so even if the motion is close to the speed of light, it should be visible on a large scale. And what we actually could see along a small part of the jet are the modifications in the jet's pattern, not the actual particles which makes the jet. There are all sorts of animations that we could show in a jet.

By the way, what are the locations of all the known plumes on Enceladus and Triton ? Someone has the data ? I need the planetocentric coordinates to place a nice plume at each location. This addon should be very small.

[Cham]

Here's the plume on Enceladus (the location isn't righ). Seems pretty nice in Celestia :

plume.jpg

The SSC code is temporary (testing purpose only) :

Code: Select all

"Plume" "Sol/Saturn/Enceladus"
{
   Class "surfacefeature"
   Mesh "comet_thin_dust_tail.cmod"
   Radius 250
   Emissive true

   Orientation [90 1 0 0]
   
   FixedPosition { Planetocentric [ -121.76 85 -14 ] }
}


Again, what should be the proper location coordinates ?