Visualisation

SWIFTGalaxy objects behave just like SWIFTDataset objects for the purposes of using the visualisation tools. Keep in mind that a SWIFTGalaxy has usually applied a mask to particles and has recentered and/or transformed the coordinate frame. The mask is one reason that it is usually best to set periodic=False when calling visualisation routines.

Warning

The swiftsimio visualisation tools do not correctly handle periodic boundaries when coordinates have been rotated. The visualisation tools cannot currently detect whether a SWIFTGalaxy object has been rotated, and can give incorrect results if periodic boundaries are used. It is therefore recommended to always set periodic=False in all calls to swiftsimio visualisation routines when passing a SWIFTGalaxy.

When a SWIFTGalaxy has been recentered (the default behaviour) the visualisation region should be given relative to the centre, not the box coordinates. For example:

from swiftsimio.visualisation.projection import project_gas
sg = SWIFTGalaxy(..., auto_recenter=True)  # the default
image = project_gas(
    sg,
    project="masses",
    parallel=True,
    periodic=False,
    resolution=256,
    region=cosmo_array(
        [-0.5, 0.5, -0.5, 0.5],
        u.Mpc,
        comoving=True,
        scale_factor=sg.metadata.a,
        scale_exponent=1,
    )
)

For general information on the visualisation routines consult the swiftsimio.visualisation documentation pages.