Lacunarity parameter determines scaling of subsequent octaves in fractal noises. For example, Noise node have this scaling hardcoded to 2.0. Each octave have twice bigger scale than previous one, resulting in finer details.
By design fractal noises that generate octaves with same seed **should never have Lacunarity set to 1.0**. Right now we simply stack up identical noises, making this node really hard to use.
Legacy textures had Lacunarity set to 2.0 by default.
User experience currently:
# Add Musgrave node, keep fBM mode.
# Detail input works differently than in Noise node. Set it to 16.
# Dimension input have no effect at all. Set it to 16.
# Now play with Lacunarity input, it looks like texture is glitching out or have no effect at all (because Dimension input is set to high)
# 😕
User experience after fix:
# Add Musgrave node, keep fBM mode.
# Detail input works similar to Noise node. Set it to 16.
# Dimension input have clearly visible effect. Set it to something between 0.5 and 2.0
# Lacunarity input is easier to control now.
# 😊