Non-uniform scaling of mesh particles

Development Rendering
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1

When generating normals witout ddx/ddy (in procedural way) to correct scales we need to use Parameters.Particle.WorldToParticle matrix then scale by 1/scale following by corresponding Parameters.Particle.ParticleToWorld call. But by unknown reason only 1/(scale^2) is working. My question is - why?
Also I’ve tried to normalize matrices rows, what gives me the same result as previous?

the code below is float3x3 m = (float3x3)(Parameters.Particle.WorldToParticle); m = float3x3( normalize(m._m00_m10_m20), normalize(m._m01_m11_m21), normalize(m._m02_m12_m22) ); p = mul(p, m); p /= scale; p = normalize(p); m = (float3x3)(Parameters.Particle.ParticleToWorld); m = float3x3( normalize(m._m00_m10_m20), normalize(m._m01_m11_m21), normalize(m._m02_m12_m22) ); p = mul(p, m); return normalize(p);

COuld someone explain me, why doesnt this work? Thanks in advance

2

So i’ve found an error, basis vector lengths of Parameters.Particle.WorldToParticle and Parameters.Particle.PsrticleToWorld are equal! thats because we need to divide it twice

3

so the code is now looks like
float3x3 m = (float3x3)(Parameters.Particle.ParticleToWorld);
m = float3x3( (m._m00_m10_m20),
(m._m01_m11_m21),
(m._m02_m12_m22) ); p = normalize(p);
p = mul(p, m);
p /= (scale * scale * scale * scale);
p = normalize(p);
m = (float3x3)(Parameters.Particle.WorldToParticle);
m = float3x3( (m._m00_m10_m20),
(m._m01_m11_m21),
(m._m02_m12_m22) );
p = mul(p, m);
return normalize(p);