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How is CG-leveled FX made?

I’m trying to make a meteor FX like in the For Honor CG:
[video]https://youtu.be/y1HkuGUaNBY?t=1m58s[/video]

This is the particle system I made, looks good enough when in a long range:
a3b5242350996c7e52618ad137310802ea46fd4e.jpeg

But the only way I can think of for the fire/smoke particle units are 2D materials and using PSA Velocity for screen alignment, then this would cause artifacts when they are behind my meteor mesh, as well as causing 2D feeling when near:


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How does these CG trailers make such FX, especially when closing the camera?
Especially with those very realistic ones like the fire spit by Smaug in the Hobbit:
[video]https://youtu.be/c4Qlqe2Ed8w?t=1m42s[/video]
Are they still using 2D materials, or are they using some simple geometric mesh with panning materials? Or even just some form-shifting meshes?
This is quite important to me as I want to and will probably make more close-range spell FX like Fire Spitting in the future…

I’m sad to say that the VFX you’re trying to achieve can only be done with pre-rendered fluid simulations that Maya and FumeFX can do, but not UE4.

HOWEVER

I’ve been looking into ways to cheat this process, and I have an interesting means of doing so. What I’ve done is make a fluid sim (say, an explosion) in Blender. (free program!! :D) I won’t cover how to make one, but there are tutorials on the interwebs. Google is your friend. Anyways, here’s a screenshot of what I have done in Blender.

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Once I’ve created the fluid sim, (which I’ve made last 64 frames at most FOR GOOD REASON) I’ve rendered it from 2 different angles: Front and Top. I could add a left angle for good measure, but I had time constraints. I chose a 256x256 render size. Make sure to save it as an image with transparency, and SET THIS OPTION or you will have no transparency ever.

rkAK42i.jpg

Now it’s just the tedious process of putting the frames into one fat image. It’ll take time, but it’s worth it.

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Save them as whatever has transparency, Import them into UE4, and make a new material, which I have set up like this:

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As for the particle system…

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I had the initial size set to 150 on all dimensions, the initial location ranging from -200 to 200 in all directions, under spawn, I lowered the rate values to 0.5, and added a burst value of this:

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And under the Required module, Set these values.

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Not only is the explosion unique from all angles, but it has volume as well. If that doesn’t look like a quick and decent explosion, I don’t know what does. I understand an explosion is not 100% what you’re looking for, but I have a feeling this process can be applied to your trebuchet tarball.

Thank you, but, I don’t quite understand the mechanism behind this. For what I understand about Cascade is that it produces the particle with material put on a 2D plane, so this will cause flaws when the viewers are near, which the 2D feeling will be obvious. In your material & particle set up I’ve only seen the same mechanism. So where does the difference lie? Is it the mechanism you used with Blender? Or the macroUV part? I’ve just read something about macroUV, that seem to be part of the solution but I haven’t tried it…

By the way, it’s good approach, I’ve never thought of that. I can tell my teammate to make particles effect for me now(Since I’m the one coping with Material & Particle, not Mesh ). Been always thinking about how should I retrieve SubUV textures from, if from youtube video it would be a very tedious work to clean all those background. Have to thank you again for solving this question of mine as well.

FWIW if all goes well, as a gamer, I believe Hollywood-level “particles” will be achieved in UE4 through Nvidia Flex: NVIDIA FleX | NVIDIA Developer

This is because then one need not “worry” about mesh or particles but focus on the simulation itself.

By the way the Elemental demo by UE4 has both a mesh displacement and particles and texture animation for the volcano:

c73651abbe0a509d6e60a6228269aa0f170d4290.jpeg