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few_a_fx

Water Sim

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So here's my new simulation. I created it by using particle fluid object, and rendered it using micro-poly. I tried PBR but the render time was between 15 to 25 minutes. Let me know what you think and if there's anything I can do to make it better

post-3609-1238013562_thumb.jpg

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PBR Render. Render out 63 frames for a test, 4 hrs and 48 mins render time. Any suggestion on how to speed it up?? Also How do you set up multiple render passes in houdini (z depth, occ, shadow,beauty, etc.)

thanks

---fughfx

post-3609-1238044450_thumb.jpg

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PBR Render. Render out 63 frames for a test, 4 hrs and 48 mins render time. Any suggestion on how to speed it up?? Also How do you set up multiple render passes in houdini (z depth, occ, shadow,beauty, etc.)

thanks

---fughfx

Many of these issues are alleviated in H10, which is quite nearby. Both speed and deep raster/AOV exports are addressed:) Stay faithful! :)

Crap answer because it means it's manual/hard process right now. Good answer because you have something nice to expect!

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Just finished rendering 85 frames. Any opinions or tips to make it better.

Hi few_a_fx, the looks of objects that are reflective and/or refractive is hard to judge in just a black background.

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Hi few_a_fx, it is looking good !

Did you render using "polygon as subdivision" ?

I think for PBR rendering you would need to increase antialias leves to 10 or 15. With low antialiasing speculars will flicker a lot.

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Hi few_a_fx, it is looking good !

Did you render using "polygon as subdivision" ?

I think for PBR rendering you would need to increase antialias leves to 10 or 15. With low antialiasing speculars will flicker a lot.

Thanks for the PBR tip, I'll try that out next. As for rendering "polygon as subdivision", what would that do and how do you set it up?

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Thanks for the PBR tip, I'll try that out next. As for rendering "polygon as subdivision", what would that do and how do you set it up?

Look at your fluid object options, in Render>Geometry tabs, there is a toggle button "Polygons As Subdivision" it will render using subdivision geometry, now it is looking to flat.

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Look at your fluid object options, in Render>Geometry tabs, there is a toggle button "Polygons As Subdivision" it will render using subdivision geometry, now it is looking to flat.

Thanks for this tip. It actually looks better. Also I realized I didn't turn on the motion blur on the fluid object. Render another 8h frames for testing now, will post it once its finished rendering.

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Just finished rendering. I changed the shader a little and added the poly subdivision on the render tab, as well as some motion blur. I still think its to clumpy looking , but whats your opinions on it?

Comp_1.mov

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here's a sample of the final render. I still don't think its perfect. still looks to clumpy or something looks wrong. what do you guys think?

final.mov

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Hi,

The pscale of the particles is too big. If you reduce it, you'll get disconnected chunks so you have to increase the number of particles. You can either increase the number in one sim or run the same sim many times with a different random seed.

Also, try appending a Smooth SOP followed by a Peak SOP to the Particle Fluid Surface SOP which helps to "sculpt" the surface.

One other thing is the Index of Refraction (IOR) in the Glass shader. The value is inversed so use 1/1.3333 for water.

Last but not least, have a bright card or HDRI map for the water to reflect.

Good luck!

Cheers!

steven

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Hi,

The pscale of the particles is too big. If you reduce it, you'll get disconnected chunks so you have to increase the number of particles. You can either increase the number in one sim or run the same sim many times with a different random seed.

Also, try appending a Smooth SOP followed by a Peak SOP to the Particle Fluid Surface SOP which helps to "sculpt" the surface.

One other thing is the Index of Refraction (IOR) in the Glass shader. The value is inversed so use 1/1.3333 for water.

Last but not least, have a bright card or HDRI map for the water to reflect.

Good luck!

Cheers!

steven

I adjusted the pscale , but the particle fluid emitter will not allow me to add anymore particles. Is there a way to over ride it, or is there a way to add more particles with out running another sim?

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You can add more particles using the particle fluid emitter. I think you have to adjust the Particle Separation parameter of the Particle Fluid Object to get more particles.

If you don't want to re-run the sim, you can use a Point SOP, or as many as you want, to offset the position of the particles using noise and merge them back together.

Cheers!

steven

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So I was only to render out about 50 frames for this test. Had to work on some other projects. But how is looking now? I think I finally got the "clumpy" look to go away. I also like how the water is building up when it hits the ground (even though you can barely see it). Any opinions or tips?

quick_test.mov

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Here's a better test render! besides being to dark and too bouncy, any thing else need changing?

Your environment is still very sober. As a test you might want to try putting an HDRI around it. As with most reflective objects you light/shape it through the highlights from the environment. Similar to bounce cards being used for lighting cars, you might want to try putting either an environment sphere around it or just some large white planes (you might have to push the white value higher than 1.0), so the water has some highlights to pick up on. Ideally you want to use Hdri so the highlights pick up on the superbright values. When the motion blur is applied they will not wash out, but instead streak out and help "read" the movement.

Also depending on the type of water you are going for you might want to add a little bit of color accumulation over depth, rather than crystal clear water.

When I was working on Jam ( http://www.sidefx.com/index.php?option=com...&Itemid=279 ), it was mainly the highlights and the seeds inside that helped convey the movement of the liquid. But if you're goal is clean water than ignore adding debris.

The motion is a lot better than in the beginning! To help fill up the volume of the liquid you can do several lower resolution sims and combine them on sop level as a bunch of points (those streams won't interact with each other but will help with the creation of the surface). This way you could add dripping from the edge of the the cylinder as a separate sim.

Good luck!

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Your environment is still very sober. As a test you might want to try putting an HDRI around it. Ideally you want to use Hdri so the highlights pick up on the superbright values. When the motion blur is applied they will not wash out, but instead streak out and help "read" the movement.

Also depending on the type of water you are going for you might want to add a little bit of color accumulation over depth, rather than crystal clear water.

it was mainly the highlights and the seeds inside that helped convey the movement of the liquid. But if you're goal is clean water than ignore adding debris.

The motion is a lot better than in the beginning! To help fill up the volume of the liquid you can do several lower resolution sims and combine them on sop level as a bunch of points (those streams won't interact with each other but will help with the creation of the surface). This way you could add dripping from the edge of the the cylinder as a separate sim.

Good luck!

Thanks for these tips pcales. I tested out HDRI (or PBR) early on, but the render time was way to long. With micro poly rendering I"m getting 3 to 8 minutes a frame, with PBR I get 15 to 20 a frame. If you know a way to get PBR to render fast that would awesome, because I really like the results I was getting with it.

As for the color, right after I posted the .mov file I added some blue to the water, but I hadn't thought about debri. I try messing around with that as well. As for the volume I'm going to mess around with the sim I have now, I think I almost got it how I want, but if it does work I've a couple people tell to use several low res sim too. So I'll probably in up using that method.

Once again thanks for your input, also if anyone has any HDRI/PBR tips for that would be awesome.

--few_a_fx

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So its been a while since I've updated this. Had so simulating and memory problems. So here's the newest video. Let me know what you think, and if you have any tips to make it better.

waterfx.mov

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