not exactly getting wetmap to work

[s_gru]

ah, sorry. ok see attached. there's nothing underneath anymore.

[s_gru]

wow scene scale really changes things. ok. anyway, here's the zip file of the scene.

[Svetlin.Nikolov]

Hey, soooo, looks like things are okay and particles are not entering the geometry. Should I look for anything particular in the scene?

[s_gru]

well when i simulate, then render, the honey shows up under the plane? could this be due to a rendered particle size or something?

[Svetlin.Nikolov]

Ah, let me explain in more detail.

So when you simulate, the FLIP liquid solver moves particles around - there are particles for the liquid, as well as for the secondary particle systems like Foam, Splash, WetMap, etc.

When you want to render the liquid, the liquid mesh (when you have set the Render mode in the Rendering rollout to Mesh, Cap Mesh or Ocean Mesh) does not get built strictly from the particles. Instead, while the simulation goes, the particles are voxelized to the simulation grid and if you have the Grid Liquid channel enabled in the Output rollout, the liquid voxels get saved to the cache files. If they are, then you will see them in the Voxel Preview. When the particles turn into a voxel grid, the shape of the liquid would change it would look like it expands somewhat.

Then, finally, the liquid mesh gets built using the voxels, not the particles, so it would also be larger than the individual particles - if you enable Show Mesh in the Preview rollout, you'll see the mesh without the need to render it out. If you are worried that it intersects the solid surface the liquid has been poured over, and if you need to render it looking from under the surface, then you could shrink this mesh or even cut out the particle under the surface.

In order to shrink it, you can got into the Rendering rollout and change the Surface Level - if you make it a higher value, the mesh will shrink - if you make it lower, the mesh will expand. It basically says around which voxels to wrap the mesh, so if you tell it to mesh only the voxels above 0.9, the liquid mesh will be smaller than the case when it contains all voxels above 0.1. Another way to shrink the mesh, and you could use both ways simultaneously, is again in the render rollout, where you could enable Mesh Smoothing and use 1 step of smoothing, and then enable Use Liquid Particles - this would allow the liquid particles to affect the mesh and you will be able to shrink the mesh using the liquid radius option under the Smoothing section.

And finally, if you want to completely get rid of the part of the mesh under the surface, you could use the Render Cutter option. However, in mesh mode it would be jagged, so you could switch to Isosurface render mode instead - beware that it would take longer to render though. Once in Isosurface mode, you can pick the surface geometry in the Render Cutter slot and if you render like this, it would render only the liquid INSIDE the surface mesh. You would probably want the opposite, so check Inverse Cutter, and it would render only the liquid OUTSIDE the selected geometry. For this to work, you gotta make sure the cutter geometry is a closed volume though. If the simulation went correct, probably it already is, but I gotta mention it just in case

Hope this makes sense, cheers

[s_gru]

makes sense. at least, it's clear to me so i'll probably have a bunch more questions. maybe i'll start a new post.