I Just Want To Simulate A Small Body Of Water

[BV72]

The title says it all, I just want to simulate a small body of water, but for some reason all of the tutorials I watched either didn't work, or I did something wrong, or they're three plus years old. Can someone please show/explain to me how I can just simulate a small body of water?

[Chala]

You're question is quite broad, and without any context on the scene your attempting to make, its hard to provide accurate advice.

There are two main ways to simulate water.
-You can bake a fluid sim.
-Or use dynamic paint to give an object movement similar to water.
(There's also particle fluids)


The one you choose depends heavily on the scene.
I suggest however, to try both. Play around, have some fun.
Here are some links :

Fluid Sim : https://www.youtube.com/watch?v=_ECgy5hawyY
Dynamic Paint : https://www.youtube.com/watch?v=0s_YBHW4tHY

With dynamic paint, make sure your object (normally a plane) has enough subdivisions to deform.

[still__alive]

Originally posted by Chala:

You're question is quite broad, and without any context on the scene your attempting to make, its hard to provide accurate advice.

There are two main ways to simulate water.
-You can bake a fluid sim.
-Or use dynamic paint to give an object movement similar to water.
(There's also particle fluids)


The one you choose depends heavily on the scene.
I suggest however, to try both. Play around, have some fun.
Here are some links :

Fluid Sim : https://www.youtube.com/watch?v=_ECgy5hawyY
Dynamic Paint : https://www.youtube.com/watch?v=0s_YBHW4tHY

With dynamic paint, make sure your object (normally a plane) has enough subdivisions to deform.

If they are for 2.8, I think they are out of date. I believe the fluid and smoke simulation systems changed in 2.82 or something. A very recent change.

[The Renderer]

What do you mean by "simulating a small body of water"? That could be anything from making a lake with a few ripples for a still image to an animation of someone pouring water into a cup. Please be (a lot) more specific.

[still__alive]

Try this video, I don't have time right now to confirm how good it is, all I can tell you is that the new fluid sim system is called Mantaflow. I'm not sure when it got added to Blender. This video appears to be about using Mantaflow.

https://www.youtube.com/watch?v=iMKoCI6UeI0

[BV72]

Originally posted by The Renderer:

What do you mean by "simulating a small body of water"? That could be anything from making a lake with a few ripples for a still image to an animation of someone pouring water into a cup. Please be (a lot) more specific.

Alright yea you have a point, what I want to do is I have a sewer scene, in which I want a few objects floating, this sewer scene will have a small body of water "flowing" down the middle, so it just have a gentle flow forwards, and a few objects bobbing in the water.

[BV72]

Originally posted by Chala:

You're question is quite broad, and without any context on the scene your attempting to make, its hard to provide accurate advice.

There are two main ways to simulate water.
-You can bake a fluid sim.
-Or use dynamic paint to give an object movement similar to water.
(There's also particle fluids)


The one you choose depends heavily on the scene.
I suggest however, to try both. Play around, have some fun.
Here are some links :

Fluid Sim : https://www.youtube.com/watch?v=_ECgy5hawyY
Dynamic Paint : https://www.youtube.com/watch?v=0s_YBHW4tHY

With dynamic paint, make sure your object (normally a plane) has enough subdivisions to deform.

Fair, sorry about that, what I want to do is I have a sewer scene, in which I want a few objects floating, this sewer scene will have a small body of water "flowing" down the middle, so it just have a gentle flow forwards, and a few objects bobbing in the water.

[The Renderer]

And you want that scene to be animated or do you want to render out a picture only?

Either way it might be simpler to "fake" this since it's a rather slow and simple movement. Instead of using a simulation.

[BV72]

Originally posted by The Renderer:

And you want that scene to be animated or do you want to render out a picture only?

Either way it might be simpler to "fake" this since it's a rather slow and simple movement. Instead of using a simulation.

The scene will be animated yes. How would I go about faking this?

[The Renderer]

It all depends on how realistic it's supposed to be (style wise) and what exactly you want to show. But, as example, you could manually animate the items to bob in the water, overlayed by small random motions to make it look more natural. Similarly you might use an animated texture to create a moving water surface.

But, again, depends on how exactly you want it to look. If you have a lot of corners or fast flowing water with visibly turbulent flows it's a lot harder.

[BV72]

Originally posted by The Renderer:

It all depends on how realistic it's supposed to be (style wise) and what exactly you want to show. But, as example, you could manually animate the items to bob in the water, overlayed by small random motions to make it look more natural. Similarly you might use an animated texture to create a moving water surface.

But, again, depends on how exactly you want it to look. If you have a lot of corners or fast flowing water with visibly turbulent flows it's a lot harder.

My entire scene is photo realistic, so I want it to be as real as possible, and this water won't be fast, its just slowly flowing in a straight line

[ChunkyButternut]

Just animate a high poly plane with gentle noise for ripples. Shrinkwrap it at an offset, and parent it, to a lower poly plane. The lower poly plane should then act like a lattice, or any other rig controller. You can use it to imply rapids, or very slightly animate the edges of the water on both sides... Unless this is in a sort of gutter in which case just rapids. Animate the bob manually for objects, or use force effects on them to make them act bouyant to the surface of your lower poly plane. You don't want it interacting with the high poly, as it might freak out.

You don't need a fluid simulation for slow or moderate moving rivers. I mean, unless there's some sort of waterfall. Make the materials right, tweak the modifiers. Sell the shot.

K. I. S. S.