Hey,

Any idea how this galaxy coloring was done? Especially the red part.
A certain way of grouping particles and coloring each group?….

https://www.youtube.com/watch?v=Hkq1v8GarjM [youtube.com]

Thanks for any ideas

Point colour and transferring Cd to a volume ?

Rob

He tells you how in the comments - (Just noticed you're probably the same guy asking in the comments )

“I projected an image onto points and baked that color into the point color value. It's pretty cheap for what it is”

It's a 2.5 million particle sim, so with comp on top, maybe a bit of blurring for the more fog volume parts (hard to tell as it never really gets very three dimensional), and some selective grading, especially blowing out the middle part of the galaxy, that could get you there.

Yes, I have read his reply and am now stuck on baking the color.
As you can see the image is projected, but as the points there color values do also. It is just moving under the image.

Any idea how to bake the color on the first frame?

James Rowe
Yes, I have read his reply and am now stuck on baking the color.
As you can see the image is projected, but as the points there color values do also. It is just moving under the image.

Any idea how to bake the color on the first frame?

Hello,

That video was made by me. Its a 10 million particle simulation (waaay over the top). At the time I was very inexperienced and didnt know what I was doing. I created a swirl of particles and projected an image on them, then sent them to a popnet and simulated some random movement and swirling. It has volume to it but it looks really bad because the color is projected on the particles and if you have a lot of volume to them then you can see streaks of color going through the volume.
Nowadays I would write a vopsop to calculate color based on density of particles. Same goes for Simulation, I would create swirling based on density, creating fake gravity and such.

Anyhoo, I looked at your file and the problem you have is that you were sending the particles into the popnet before baking in the color. This meant that all of the particles coming out of the popnet got assigned the color on every frame of the animation. If you assign the color before sending them to the simulation, then the color sticks to the particles. This however poses a problem where you need to create the particles before sending them to popnet (which is what I did in your file)

Attached is the corrected file.

Hey Ignas,

Thanks for taking the time to help. I replied on your video before seeing this post about caching one frame with a cd and sourcing from that (which works), but I understand that's not needed and assigning color before the popnet as you have shown is correct.