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The most important part of the extension functionality resides in loadMesh, which must be implemented. The rest are optional functions. getBoundingBox, if implemented, returns the maximum and minimum points of the geometry's bounding box, in local coordinates of the object. This function is called at the voxelization stage, just before starting to render.
One of the other three functions getProxyDisplay* should be implemented if the extension writer wants to draw an approximate proxy of the object in the Studio viewport. For example, the MaxwellGrass extension uses getProxyDisplayLines to draw some lines representing grass strands.
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