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AmigaNewTek
12-17-2012, 05:32 AM
Hello there,

what's the best way to simulate a giant storm with massive lightining in the clouds?
I'm rendering a planet with the camera from top pointing at the high orbit of the planet.


Thank you in advance for any advice.

BeeVee
12-17-2012, 07:20 AM
You can't see lightning above the cloud layer, so just a flashing point light below a translucent object should do fine.

B

AmigaNewTek
12-17-2012, 08:42 AM
I tried using a fake cloud texture in the luminosity channel, using an envelope for fast oscillating luminosity values. This works, but the lightning appears in strage position on the planet. Even if i remove the fake textures, the lightning appears on strange places.

AmigaNewTek
12-18-2012, 03:20 AM
Anyone?

prometheus
12-18-2012, 12:51 PM
I did some test long ago with hypervoxels around a planet, one null with Hvīs which was cut off with nodes to try fit a spherical cloud around the planet, I did also test a small lightning within that, looked good, but
took extremly long too render actually, unfortunatly I do not have acess to those files right now, on a computer that needs fixing.

I used a point light with envelopes and simply placed it accordingly where it was needed below the cloud hv textures.


Michael

prometheus
12-18-2012, 01:37 PM
heres how a more stylized HVīs (one single null) than realistic cloud on a planet could look like with hv experiments I did some time ago, I tested a point light beneath the hv cloud layer, and with falloff, so that works and gives a nice lightning effect that illuminates beautifully when set to rayleigh mode, took very long to render thou..so at the time I gave up, would like to go back and test again if I find the files that is:)

Canīt show any lightning samples though.

Michael

AmigaNewTek
12-19-2012, 09:38 AM
Thank you for the reply.

I did some test using a fake cloud layer, copying only the parts i need for the effects. Subdiving the fake layer into more polygons, you can get a fine grained texture that will match exactly the underlaying clouds layer. If you make it flash with an envelope in the luminosity channel it's seems that there is a thunder storm in a specific area. I will try your suggestion.

Thank you

AmigaNewTek
12-20-2012, 02:47 AM
@prometheus
Could you, please, tell me how you realized a single (stylized, not rounded) cloud with hypervoxel?

Thank you

prometheus
12-20-2012, 06:29 PM
@prometheus
Could you, please, tell me how you realized a single (stylized, not rounded) cloud with hypervoxel?

Thank you

Have to get back on that later this weekend, christmas business and some other things first, you might get a hint by checking the node setup in this image..thatīs what I used anyway.
But itīs a little more to it than that , including tweaking hypertextures,density, thickness,texture value etc.

Michael

jeric_synergy
12-20-2012, 07:32 PM
I tried using a fake cloud texture in the luminosity channel, using an envelope for fast oscillating luminosity values. This works, but the lightning appears in strage position on the planet. Even if i remove the fake textures, the lightning appears on strange places.
y'know that saying "A picture is worth a thousand words"?

prometheus
12-21-2012, 03:07 AM
I got some interesting results trying out the dpont raindrop procedural texture in hv luminosity channel, could be used on opacity as well, Of course..setting up a light that hv rayleigh illumination model
reacts too would be the most beautiful result, but setting up lights takes a lot longer to do and more time to render, so I will try some cheating with the raindrop texture first.
it has animation parameters built in which suits very well for simulating different impact or ligth release..maybe, I will work on it more this weekend.
Thereīs also an option to use dponts particle paint ..so when particles hit the area of Lightning interest, it illumates hvīs too.

placing a point light and set a good flash lightning, clone the light, and just move the time slider in the envelope for the second and even third light will do too, im curious if there is a fast way to
match very realistic lightning flashes, with noise, or using real life shots to drive it somehow, it sure has it characteristics 1,2-1,2,3 in and out flashing..or something like that:) I think that is the hard part..the
natural timing of the Lightning.

As for the voxel cloud, the node shown above has a gain function to cut of the inside of the voxel volume, not sure that is necessary though, you can also use smooth step function which I think Has more control.
As mentioned, I had to start from scratch again with planetary clouds, since the work I did before is unavailable right now due to hardware issues with that computer, I will fix that after christmas if I get to see santa that is:)

Michael

AmigaNewTek
12-21-2012, 04:00 AM
Have to get back on that later this weekend, christmas business and some other things first, you might get a hint by checking the node setup in this image..thatīs what I used anyway.
But itīs a little more to it than that , including tweaking hypertextures,density, thickness,texture value etc.

Michael

Thank you. It's interesting.

prometheus
12-21-2012, 11:27 AM
I just put together a very simple scene, wrong scale and nothing special really, but you have to have the dpont particle paint procedural plugin installed.
just a simple plane that reacts to particles, so the luminosity is triggered by the particles.

so no hvīs here, I just wanted to check out the triggering and look of particle paint, forget about the raindrop procedural, that wasnīt giving good enough results, this is more promising.

I have sent a suggestion to Dpont about creating a procedural that can generate natural flash lightning in proper time manner if that is possible to do, then you wouldnīt need a particle system
to trigger it.

will try with hypervoxels too later.

load the scene, load surface panel and have viper open and hit f9 first, then use viper to make preview and playback, it is still faster to use as previewer than VPR since you have emmidiate acess to
make preview and playback, hope they work something like that out for VPR as I have mentioned a couple of times before.

Michael