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Here you can enter a custom value for the mesh’s polygon size. Smaller values lead to larger mesh files, but also more detail. Lower “@ polygon size” values take longer to calculate and need more resources. Please note that “@ polygon size” is not responsible for the rounded look of a fluid’s borders. If you want to avoid rounded borders, filters and “Radius” settings are of much higher importance. A sufficient amount of particles is also needed. Finally, the look of a mesh strongly depends on your scene scale.
Please read the “How to Adjust the Mesh's Polygon Size” chapter for further information.
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