The dialogue for grid fluid meshes is based on the characteristics of this particle type. Grid fluids only represent the core fluid of a large scale simulation and therefore, only a limited number of possibilities is required.
UVW Mapping
“None” disables this feature. “UV particle” takes the particles’ UV coordinates into consideration and creates an UV grid for the mesh. This mapping type can sometimes lead to distortions “Top projection” is just a flat projection method, so the map becomes stretched and distorted at the mesh’s edges. “Top projection (average velocity)” uses the same mapping method as the previous option, but it is based on the fluid’s velocity.
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