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I've been messing around with dynamic paint to create wet map for fluid sim in the past couple of days. It's hard to put this into word but, I still can't figure out why the paint kept skipping some parts, although I have set all the substeps fairly high. These are the settings for my Dynamic Paint Brush and Canvas:

Brush

Canvas

And, these are the setting for the fluid simulation (Flow source and domain)(I'm using uni-cache): Flow

Domain (At one point, I've set the min and max substeps to 10, but it still output the same result.)

This is the overall scene: Scene

And, these are the results of the dynamic paint. I have messed with all the settings from low to high substep but it outputs the same image with the same problem, the paint kept skipping some parts. img1 img2

I would really appreciate if anyone can help me in this issue. Thank you! Blend File: https://drive.google.com/file/d/1FuSG6xQC27zlylR4GSbtzq0iS729f3_y/view?usp=sharing

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    $\begingroup$ Can u provide blend file? $\endgroup$
    – Chris
    Jun 27 at 4:27
  • $\begingroup$ done, I have added the blend file, please give it a check and see if you found any problem, thanks! $\endgroup$
    – Albert
    Jun 27 at 10:19
  • $\begingroup$ I just smell it is not supported ... sub-frames for sim are to prevent leaking due calculation sim, but result is frame by frame shape of liquid that is totally different in meaning of topology than in previous frame ... so I thing there is not a way to store shape (vertices) motion in between frames ... sub-steps in DP is able recalculate in-between frames from linearity of object or vertex motion. That is something that is not happening here ... if I'm right ... I'm going to check your file ... $\endgroup$
    – vklidu
    Jun 27 at 14:26
  • $\begingroup$ Aww, that's a bummer. Anyways, thank you for spending your time to help me, I appreciate it! $\endgroup$
    – Albert
    Jun 27 at 15:08
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Timesteps and Substeps in fluid sim are aiming to prevent from leaking due calculation, but result is frame by frame shape of liquid that is totally different object (in meaning of topology) from frame to frame ... so I thing there subs are not store as shape (vertices) for reuse for DP.

Substeps in Dynamic Paint are able to be recalculate in-between frames from object loc/rot/scale or vertices, but that is not happening here in case of fluids ...

You can simply to check that if you go to Output Properties > Dimension > Time Remapping > New 400 ... as you can see, Cube has a statement for every frame ... Fluid object each fourth.

enter image description here

So ... the only one thing that can be a solution ... is to change a speed of fluid-sim to slow-motion ... Bake DP and speed it up or render each n-frame.

Easily to set with $ FlipFluid addon by Speed value, but with blenders fluid solver I tried to lower Time Scale, that make sim slow, but result is totally different from original sim ... it can be just I don't know how to use it properly (but I can't find any tut covering slow motion with Mantaflow). Sorry

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