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Changing “Open boundaries” to “Yes” will unlock the “@ extension” parameter.
@ extension
When this option is active you have access to the parameters below. As the name indicates, an extension is a method of enlarging the mesh surface and creating the impression of an endless (or at least very large) ocean. When an extension is created, the mesh engine adds a given number of tiles to the original surface and blends them together. The core fluid simulation can be seen as the centre of the ocean. With growing distance from the centre, the mesh's resolution decreases – the polygons become larger. Additionally, you can observe a denser polygon zone around the core fluid mesh which describes the transition from the high-resolution to the low-resolution part.
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By default, the mesh engine calculates the current sea level automatically (in world coordinates). If you want to adjust the level, please change this option to “No”. Then you can enter a new value under “@ Sea level”. Please note that the found value is also displayed in RealFlow's "Messages" window. This value can be copied and pasted to "@ Sea Level" to save time during the meshing process.
@ Sea Level
This parameter is only active when “Sea Level Auto” is set to “No”. With positive values, the surrounding tiles will be displaced. When “@ Sea level” is negative, the tiles are lowered and the core fluid will be embossed. With positive values, on the other hand, the result is an immersion around the core fluid.
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