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Colour modes and colormaps

Halo colour modes

Selectable from the Structure tab:

Mode Scalar Range
Mvir log₁₀(Mvir / Msun) 10 – 15
Rvir log₁₀(Rvir / Mpc/h) -1.5 – 0.5
Vvir log₁₀(Vvir / km s⁻¹) 1.5 – 3

Galaxy colour modes

Mode Scalar Range
Stellar Mass log₁₀(M★ / Msun) 8 – 12.5
sSFR log₁₀(sSFR / yr⁻¹) −14 – −8
SFR log₁₀(SFR / Msun yr⁻¹) −3 – 2
Cold Gas log₁₀(M_gas / Msun) 7 – 11.5
Bulge Mass log₁₀(M_bulge / Msun) 7 – 12
B / T bulge_mass ÷ stellar_mass 0 – 1
BH Mass log₁₀(M_BH / Msun) 4 – 10
ICS Mass log₁₀(M_ICS / Msun) 6 – 12
Age mass-weighted stellar age 0 – 14 Gyr
Density KDE local density (categorical / per-snapshot normalised)
Type Central (Blues cmap) / Satellite (Reds cmap)
Structure Multi-layer composition — see below

The inline colorbar beneath each Colour-by dropdown reflects the current mode's range and the current colormap.

Structure mode

A more physically-suggestive galaxy rendering. For each galaxy:

  • a black BH core sized by BlackHoleMass
  • a blue cold-gas envelope sized by ColdGas
  • coolwarm-coloured "stellar particles" scattered inside the envelope; particle count scales with stellar mass
  • an outer envelope coloured green (CGM regime) or red (Hot-atmosphere regime), sized by H2gas or ColdGas
  • sparser coolwarm scatter through the outer envelope

All layers stay within the standard galaxy splat-radius scaling so the overall on-screen size matches the other modes.

Colormaps

27 colormaps available in both the halo and galaxy colormap dropdowns:

Sequential : Viridis, Plasma, Inferno, Magma, Cividis, Turbo, Blues, Purples, Greens, Oranges, Reds, Greys, YlOrRd, YlGnBu, BuPu, Hot, Cool, Bone, Copper

Diverging : Coolwarm, RdBu, Seismic, Spectral, BrBG

Cyclic / qualitative : Twilight, Jet, Rainbow

Point sizing

Splats are rendered in world coordinates (Mpc/h) via vtkPointGaussianMapper's per-point scale array — so when the camera zooms in they grow on screen, and when it zooms out they shrink. The radii are scaled by the underlying mass:

  • Haloes: 0.15 – 1.5 Mpc/h (log₁₀ Mvir 10 – 15)
  • Galaxies: 0.025 – 0.35 Mpc/h (log₁₀ M★ 8 – 12.5)