How to get scale from localToWorld component?

Unity Engine
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1

Do I need to use matrix to calculate scale myself somehow?

2

LocalToWorld just contains a 4x4 float transform matrix. If you know for sure the specific value represents an affine transformation without shear, you could use TransformHelpers.Scale.

public static float3 Scale(in this float4x4 m) =>
            new float3(math.length(m.c0.xyz), math.length(m.c1.xyz), math.length(m.c2.xyz));

(source)
There’s also math.decompose which you can use to recover translation / rotation / scale in one go, still requiring an affine transformation without shear:

float4x4 v = ...;
math.decompose(new AffineTransform(v), out float3 translation, out quaternion rotation, out float3 scale);
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