With the "HY_Domain" node's s → “Display” panel it is possible to preview the areas where splash particles will be created. For this purpose, you will find a couple of threshold values. These parameters are exactly the same as you can find under the “Splash” emitter's “Splash Creation” tab, but they will not create any particles. Their only function is to make the splash emitting particles visible. To activate this feature, choose:
Grid fluid domain node > HY_Domain > Node Params > Display > Property > Splash/Foam preview
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