In this post, the EarthQuake said - normal maps are 24 bit whereas regular bump maps are only 8 bit WHY? https://polycount.com/discussion/36160/bump-map-vs-normal-map
Normal maps holds negative and positive values too, while bump maps only holds positive. I know this is confusing, because people author normal maps as 8 bit and only positive, and it gets hdr range in the shader. So its kinda happening in the background. With all this said, you could still author bump maps as hdr. Also,…
Also there can be a difference in nomenclature. If people talk about 8 bit vs 24 bit they might simply address the number of channels of a 8 bit texture. Bump is just one channel (Grayscale), so 8 bit. Normalmaps have 2 (when the third channel is calculated from the two) or 3 channels (RGB). 3 x 8 = 24. But it does make…