I’m looking at the numbers from a sphere primitive. I would have though that all the numbers would be between -1 and 1 but I see a 2.9 in there. Can someone explain how vertex normal works?

vertexData.vertexNormalData = 0,1,0,0,1,0,0,1,0,0,1,0,0.8660254037844385,0.5000000000000001,0,-0.433012701892219,0.5000000000000001,0.75,-0.4330127018922197,0.5000000000000001,-0.7499999999999998,0.8660254037844385,0.5000000000000001,-2.1211504774498133e-16,0.8660254037844388,-0.4999999999999998,0,-0.4330127018922191,-0.4999999999999997,0.7500000000000002,-0.43301270189221974,-0.4999999999999998,-0.7499999999999999,0.8660254037844388,-0.4999999999999998,-2.121150477449814e-16,1.2246467991473532e-16,-1,0,-6.123233995736764e-17,-1,1.0605752387249072e-16,-6.123233995736772e-17,-1,-1.0605752387249067e-16,1.2246467991473532e-16,-1,-2.999519565323715e-32

You’re right that normals should be normalized, i.e. none of the components should be larger than 1 or smaller than -1.

The number that you’re seeing is 2.9995e-32. Note the e-32 part which is “scientific” notation for a 10^(-32) multiplication. So this is actually a value that is extremely close to zero, and well under 1.0.