Krakatoa

#1761

Go get the latest build from the public beta folder.
http://www.thinkboxsoftware.com/krakatoa-downloads/builds-beta/
Obviously I am using something that your version of Magma does not have.

#1762

Hey guys I have a particle simulation. 6million particles. I want about 20% OF THE TOTAL PARTICLES TO GLITTER. How can i do that with magma flow.

thanks

#1763

Take the id and use the mod operation, that gives the remainder of division. Mod with 5, and for the particles that the result is less than 2, you can make the selection channel 1. Then in a separate magmaflow you can use that selection to make them glitter.

#1764

Glacierise thank you so much for your reply… As i have never used krakatoa before so i am still on a learning curve. I tried to do something as per ur guidance. but i dont know if i am doing it right or wrong. so please help me out with it.

check jpg files for the magma flow connection i used for it. its not working so i am sure i did something wrong.

magma flow1 i used for selection and magmaflow 3 for glitter.

please help me out with it. thanks :slight_smile:

#1765

It is really not necessary to have two flows for this.
I would suggest you figure out how you want to implement your glitter on 100% of the particles first (your glitter flow makes little sense to me, but I might be misunderstanding something). There are many ways to do the glitter, but let’s assume you want to modify the Color over time via a Noise based on some input parameter (probably not Density, but current time + ID or Position or something like that). Then simply create a Logic Switch operator that is set to True when your Modulo operation produces the expected result, and set the Color output to the modified value, otherwise set the Color to the input Color channel without modification. This way, the percent of particles that pass the Modulo-based test will change their color and the others won’t…

Start with 1000 or so particles and figure out how the flicker should work. Then add the Logic for the percentage. Then apply to the millions of particles…

#1766

Hey Bobo. thanks for the awesome plugin. back to the topic. i took ur advice. and got something to work. but it is still not looking really like that… i am sharing you my kcm script please. have a look at it. thanks a lot

#1767

hey sorry… this one makes more sense and it is more cleaner… i thought i cannot plug in vector to switch so i was converting them to scalar. lol my bad.

#1768

Does not look like something that would work…
I have attached a possible solution based on the ID channel (assuming there is one, you can switch ID to Index if not), and the current time to cause the Noise to change over time.
There is a control which affects the Nth particle (when set to 5, every 5th particle will change color, the other 4 will keep their color). Also there is a value controlling the strength of the Noise.

#1769

:applause:that works like a charm… thanks for that… :slight_smile:

#1770

Hi, Bobo, i send you a message, but, post this problem anyway. Using PRT Hair have this issue
My render crash when i try to render more than 40000 hairs with the hair and fur modifier, with no splines. A message like "out of memory " appears and dont do the render.
Have no problem with less that 40000 hairs.

Any help??

Thankss!!

#1771

Could it be that you are actually running out of memory? :slight_smile:

Please post the version of Max, Krakatoa and Windows (32/64 bit?), as well as your hardware specs.

I just created a Teapot, added a Hair&Fur modifier and requested 50,000 hairs with all other settings at default. I did this on my laptop (dual i7, 8GB RAM). My RAM was already at 5.5GB due to too many tabs in Chrome, but Krakatoa only used about 165MB of RAM and rendered 6.1 million particles from the 50K hairs without a problem.

Open Task Manager and watch your RAM while you are trying to render. Do you see any spikes?

#1772

Hi, BObo, thanks for the reply.!
I have i7 processor, 16gb ram, win7 64bits, max 2012, Krakatoa MX 2.0.1.46319.
And your right, i`m out of memory with 60000 hairs.
But, i do a test with more spacing that 0.1, and its render, the problem is that the particles appears to spacing, dont look like hairs.

Is splines a better method?

thanks.

#1773

Do you get any feedback about the number of particles it tries to create?
Normally, Krakatoa on a 64 bit system should never run out of memory.
Also, have you tried the latest beta 2.1.4 build posted on our website? It is possible that we fixed something since your build was released…
http://www.thinkboxsoftware.com/krakatoa-downloads/builds-beta/

#1774

I´m trying to render my RealFlow Grid Domain particles using Krakatoa, but I only get a black picture…

I load them with a PRT loader and i can see them in my viewport but as soon as i render (wit a simple light) I get a black picture. If I load my Splash particles insetad everything renders fine…

My Grid Domain have almost 15 million particles but that shouldn´t be any problem, right?
Any ideas?

Sorry if this is a stupid question - I´m new to Krakatoa so there will be some newbie questions…

Cheers

#1775

Have you checked the alpha channel in your render window to see if the particles show up there? It could just be that you need to have more lights and adjust your density.

#1776

Thanks for your quick reply and yes I have checked my Alpha but its just black - empty picture…

When it renders it calculates the light and retireveing the 14.5 million particles and renders…
Just black. Very strange.

I use a PRT loader to load my .Bin file - If I load my splash or foam it works fine… They have much less particles but I have rendered alot mor particles than 15 million in krakatoa!

#1777

I think I found the problem… I tried to override my density with a pure white and then it renders fine… Why my density is black from realflow I don´t know…

Cheers

#1778

I have run into this as well.

You can also add a KCM to the PRT Loader, just pipe a float of 1.0 into the density channel.

EDIT: Sorry for the short reply I was sending it from my phone. The actual grid.bin (if that is what you are using) appearantly does not populate the density channel like a normal realflow emitter object would so you need to add a value into the density. You can get fancy with it by introducing some of other channels such as velocity or vorticity and do some basic math functions on them to get some different effects.

#1779

RealFlow has its own Density channel which means something else completely. Under certain conditions, it might get set to 0.0 (I think one case was reflowing particles through a Hybrido simulation to produce Vorticity, but that was a few versions ago and there might be other cases too).

So you need to reset the Density of the particles to 1.0 as suggested by others (and as you have found out already). A Magma modifier is the better solution.

#1780

Ah, sorry, I keep calling them KCM’s, old habits.

I realize they still exist but are depreciated.