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I have read the Blender manual regarding bump maps and normal maps. But still it is not very clear to me when you would make or use bump maps and when normal maps. Who can explain ?

Ray Mairlot
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1 Answers1

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Bump maps and normal maps are essentially the same thing. The primary difference is that normal maps have more information in them(because they use an rgb input) to give a more accurate bump effect. The rgb information in the normal maps correspond to the x,y,z axis.

Bump maps use only a black to white map to understand the depth.

Both bumps and normals are essentially a way to cheat the shading to give the effect of depth...meaning no resolution is added to the geometry in anyway... to do that that we use displacement maps. Displacement maps unlike the other two actually modify the geometry at render time.

Hyenaman
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    thanks. Could you maybe explain when you use normal maps and when bumps maps ? I guess there are reasons when you chose to use the one or the other ? –  Sep 15 '16 at 13:28
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    @OldMan - it depends on the purpose of your model. Since normal maps hold more accurate information they are the preferred method of faking geometry light reflections. There might be some older or simpler real-time 3D engines which are not able to user normal maps. Other than that, you can always convert a normal map to a bumpmap without loosing information. – metaphor_set Sep 15 '16 at 14:11
  • This short concise answer made things so much clearer for me than all the tutorials I've been watching. – deanresin Nov 03 '17 at 22:54
  • @metaphor_set I don't understand how normal map can be converted to bump map without losing information. Normal map has 24 bits per pixel and bump map has 8 bits per pixel (since bump map is black and white). Correct me please if I'm wrong. – Cake_Seller Слава Україні Jan 11 '21 at 19:09
  • @Cake_Seller - converting a normal map into a bump map gives you two textures, if you don't save over your normal map, that is. If you need bump maps for a niche solution, you can convert normal maps (and keep the originals) without loosing information for your niche solution. However, you are not able to convert bump maps into normal maps without loosing information. – metaphor_set Jan 12 '21 at 07:03
  • It sounds like bump maps are simply displacements maps. Is this accurate?.. Or is there a difference between those as well? – Jack Avante Jan 21 '21 at 13:15
  • @JackAvante There's an answer to that at the end: – Heath Mitchell May 23 '21 at 19:11

  • Displacement maps unlike the other two actually modify the geometry at render time.

     – Heath Mitchell May 23 '21 at 19:11
  • Bump/normal maps just add a fake depth effect y changing the direction that light bounces in and displacement maps can add real depth/parallax – Heath Mitchell May 23 '21 at 19:12