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patrykcieslak / stonefish

Stonefish - an advanced C++ simulation library designed for (but not limited to) marine robotics.
https://stonefish.readthedocs.io/
GNU General Public License v3.0
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Drag computation for compound hull #27

Closed silent-code closed 2 years ago

silent-code commented 2 years ago

On line 324 of Compound.cpp, it states that drag is computed for externally declared parts that are submerged. That makes sense. However, does the app compute drag for the hull, for example, in the following declaration of the compound vehicle hull since it's not explicitly labeled as 'external'?

//Build whole body sf::Compound* vehicle = new sf::Compound("Vehicle", phy, hullB, sf::I4());

silent-code commented 2 years ago

@patrykcieslak: Hi Patrick, can you clarify this matter? Just wondering if the above declaration gets included in the drag computation since it's not explicitly labeled external?

Thanks, Tim

patrykcieslak commented 2 years ago

Hello! If you looked into the header file you would see that the part that is passed to the constructor is called "firstExternalPart". My thinking was like: if there is some physical body made of parts, at least one is gonna be external, so let's force that the first one passed is external. Actually, when I think about it now, it may be unnecessarily restrictive, because maybe you want to combine some internal parts into one and then declare the external ones separately... Sorry for not responding earlier!

silent-code commented 2 years ago

Thanks Patrick! I missed that in the header!