You can use any triangulated object with this emitter. The outside faces of the object will be used to create the particles along the polygons' normals. If the normals point to the inside the object can be filled.
Type
Toggle the emitter's type with this drop-down menu. The following parameters and the viewport representation will be updated according to your selection. Bear in mind that type changes will change the emitter's and fluid's behaviour completely.
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Here the particles' initial speed is defined in metres per second. Higher values will generate more particles per frame. Faster particles act with stronger forces on other particles or objects. The number of emitted particles also depends on the domain's “Resolution” settings. A value of 0.0 → stops the emission of particles.
The chessboard indicates that you can use bitmaps with this emitter:
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