Blender | Normals, Normal Maps, and Bump Maps Explained
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- Опубліковано 10 гру 2021
- Hey, this is a video that I made to explain normals, normal maps and bump maps, specifically from the lens of blender. I wanted to make this because while there are others in this general vein, I haven’t seen any that look at the whole topic holistically and pragmatically, not just looking at what, but also at why?
Link to the example material:
freepbr.com/materials/steel-p...
Chapters:
00:00 Intro
00:20 What are normals?
01:53 Smooth shading
03:19 What are normal maps?
04:57 Where do we see normal maps?
05:32 A brief tangent (how normal maps work)
06:16 How to use normal maps
07:31 What about bump maps?
08:06 How to use bump maps
08:34 Use distance not strength (IMPORTANT)
09:22 Bump maps vs. normal maps
10:45 Recap
12:03 Outro
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While watching this, you might notice that my vocal delivery isn't very good. You might also notice I recorded this at 4 am. Maybe I would have eaten fewer words if I had any semblance of a sleep schedule. - Фільми й анімація
Finally a video explaining "how it works" and not "how to do". If any of you can share some other ressources of this kind, it would be great ! 👍
Can't wait to watch more videos from you !
The quality of this video is insane, clean and simple explanation ,please keep the good work :). +1 sub
Bump maps are easy for the user to mess with, but more costly for the renderer as it has to lookup neighbouring pixels in the map and calculate the normal. In a normal map, the normal comes directly from the color and no additional computations are necessary.
Normal maps can store a gradient with a single color that doesn't correspond to flat, whereas a bump map would require a gradient. Therefore bump maps may require higher resolution images and at higher bit depth to avoid banding effects to show up, especially at high zoom levels. Cubic interpolation can help, but it won't do magic.
Using normal maps the normals are independent on density; a 5 degree tilt will be 5 degrees no matter how dense you repeat it, but the height perception will vary instead. It's opposite for a bump map; put those peaks and valleys denser together and keeping the height, the normals will vary. Use *ONLY* normal maps whenever depicting known angles are critical.
Normal maps can be tricky as hell to manipulate (blend, rotate) if you want to do it correctly. Sure, simple overlay may work *good enough* if angles aren't critical, but it won't always work as intended if doing texture bombing, triplanar mapping, or you can't be bothered to setup proper UV space.
Personally I usually work with bump maps instead of normal maps; the hit on offline rendering isn't that critical for me, I (usually) can deal or work around the downsides, and they're just far easier to manipulate whenever I want to eliminate seams or texture repeats. I also like to randomize the look of the assets I use multiple times in a scene, so baking out a normal map just doesn't work that well for me. Normal maps are technically the better option result wise, but often convenience just wins for me.
OK. So, if I understand correctly, normal maps essentially take the geometry that pokes out of a plane and flattens it into a hologram as part of the texture. In the same way that a hologram can be seen from a bunch of different angles and show different shading depending on the direction and intensity of the light source, it _cannot_ cast real shadows on anything around it that weren't captured as part of the holographic process that made the image. I guess another way to think of it would be like if the surface was made up of flat LCD panels (with absolutely perfect 180° viewing angles). You could make it so that those panels react to things like lighting and viewing angles with cameras and tracking and such to make the panels display a reasonably convincing illusion of depth that reacts to the viewer, but nothing can ever poke up past the surface of the screens used on each surface. This means that the different colors in a normal map are a bit like looking at an anaglyph 3D image (the old red and blue type of 3D) without the glasses. The more the color is distorted away from that flat, magenta/lavender-ish color, the more that the original protruding shape is being flattened down to a plane.
By contrast, a height/ displacement/ bump map _can_ cast shadows, since it's essentially just a way of storing Z axis data in a flat image. Height and displacement maps are _basically_ the exact same thing, the only difference being how the engine renders the same data. A height/ bump map uses the same sort of "hologram" method that keeps the surface flat, while a displacement map _will_ actually poke out from the surface (and cause a bunch of geometry to be added)
Please correct my horrible interpretation of these concepts.
Normal maps (and I think bump maps?) cast shadows that react to dynamic lights, but the actual polygons still looks flat from the sides.
The displacement map doesn't create new geometry, it just modifies the existing geometry, but for best results you would want a fairly dense mesh.
This is a really good video, not everyone can explain stuff like this so well
Best video on the subject by far. Thank you
Thank you!! This was a life saver!!! My textures were looking pretty weird after I used my normal map, which made me panic. Then, I remembered the extra nodes that go in between, but wasn't sure if I needed them. You helped me understand what exactly I needed, and I am quite happy with how my texture looks right now!!!
awesome video! Thank you
the recap is great!!! thanks
Keep it up! Really well explained video 👏
Great video! Thanks!
Perfect video!
Thank you for making this! Great and simple explanation!
Phenomenal tutorial. Thank you.
Underrated channel
Wow! Nice video!
amazing, This video made my day
that is just amazing, simple and full of info. Ty for this video
Excellent video! 10/10
very good explanation!
In love with this summary! +1 sub
wow i like that tutorial- well structured, funny, and the editing is fancy
Very useful video! You explained everything pretty clear. I hope you keep posting videos and your channel grows !! ❤❤
That was helpful. Thank you for sharing your knowledge
I hope you get big on here 👌👌
Lovely simple and clean explanation 👌👌
Thank you for this video! It's very informative and well made
Highly underrated video, thank you for it!
Simple explanation. One of the best videos on the topic. Also loved your style of presenting.
But hey, why did you stop posting? Want more videos from you mate.
Amazing video! I have taken away a lot of useful information from this, thank you!
This video is soo helpful and well made, its crazy that you dont have more views and subs. You def deserve them.
Me gusto mucho ese video, quiero mas
Wow really good, hope you come back to make more videos like this
Thank you I was just making a procedural material and I realized I had no idea how to generate a normal map for it, this fixed the issue!
sir , you deserve more subscribes
Mannnn you are great, keep up the good work!
Subscribed!!!
This was incredibly helpful. I've been messing around trying to learn Blender inconsistently for a few years now and I finally understand how this works. Thank you
wow Dude_ this explanation was awesome. Can't believe this hasnt got more views
I was searching for "blender bump maps", and the decision stood between this longer video, or the shorter one. I decided to give your video a chance, and earned you a new sub. I learned a lot of new things from this video, and got new ways to look at, and approach, bump maps. Thanks alot!
You cant even imagine how much I thankfull to you! This is the best explanation with examples and the most important differences and when should I use both maps. Thanks again!!!!
Maan, more of these. I need these type of video explainer about blender stuff.
best explainer video for this I have found
cheers that is a good tutorial , thank you so much
lifesaver!
Awesome explanation! keep it up man.
Here's my subscribe :)
thanks!
i like your video, thank you, you are so smart!
You are soooo good. Want to see more videos...
Great video! just a small clarification in 5:45. the Blue channel is actually used to normalize (make all of the vectors the same length) the vectors the Red and Green channels produce, it's just faster having it stored in the Blue channel than calculating that when rendering, but really, you have all the info you need in the R and G channels.
Dope
earned a sub gg
quality video
easy use bump, normal sometimes get wrong direction such as openGL type or direct x tipe if we download from internet. btw Good explanation
That was what I have been searching for for soooo long thank you. You almost got there but is there a way to use a normal and bump map, or is this simply not a thing or required as one cancels the use of the other?
you earned a hard to earn subscribe
6:14 the larch
More pls
great explanation! btw you talk like chef john
damn dude only got 98 subs?
name of background music?
Wait a minute, you do the music in your videos too?
THE BACKGROUND MUSIC IS JUST FUCING HEADIC
PLease try to talk slowly! you are talking very fast~