No, not hard, if you know use material setup. Or you can use Texture Paint. On Youtube maybe you can find any tutorials labeled DECAL.
I know how to use decals, but if I want to comp an alpha of some grime under the windowsill of a building then to get it the right size, position and transparency, and to mask it is so much easier in a paint program. A coffee stain on a table is a similar example of motivated detail.
Decals mostly use for interacted scenes. If you want fixed scene or texture, yes, you can easily use Photoshop or Blender’s Texture Painting.
The problem is that you’re heading at a wrong direction and just blindly consume all the tutorials without spending any extra effort (or time) in really understanding the logical executions behind how shading nodes work for Blender and how you’d use those nodes to create shading materials yourself… One thing I’d suggest is that just take a step back, spend a little bit less time consuming those tutorials and try to learn how the actual logic behind shading materials and node works in 3D general and in Blender specifically… There’re tons of shading learning materials online and if you put even only 10% of effort in reading and trying to understand the logic behind it, it’d make much more sense for you when it comes to creating materials…Most of the logical execution behind nodes are mostly mathematic (the basic ones) so if you understand it clearly, it’d not bother you that much…Or not, spend sometime fiddling around yourself and try to understand the nodes function would be another alternatives…Probably won’t get you to something that’s fancy or advanced, but it’s enough for you to get around and feel comfortable using the system…
At a point I would give up trying to understand how all the materials are done, what all the nodes are for, how to do all the materials, it would be like trying to understand all the photoshop tools when not half of them are really useful to me, I would rather work on a personal project, meet difficulties, and solve them, that’s all. This way, on the next project, it will make the things a bit easier and my comprehension of nodes a bit more advanced. I thinks it works for all the aspects of Blender.
Material creation is really hard work. If you want realistic or PBR material creation, then firstly you must learn a little optical physics.
I appreciate your sentiment, as a matter of fact, I’m a physics grad student lol. I know standard optics, perhaps into a little more depth than an average person (I know what Fresnel is, or why visible light does not pass through metals etc.). I know how these translate into Blender and what the basic sliders do however, when people start adding Voronois, waves, and start mixing them with various sliders, I’d argue that this has little to do with the knowledge of optics and is more about experience or trying hard and long enough until it “looks right”. How they got there is not apparent to me from their tutorials…even as I’m creating it along the tutorial, it barely looks right to me until the last node mixing everything together is connected to the base color and everything comes together. I never see it beforehand.
For realistic material creation, you can watch CgCookie’s paid ShaderForge tutorials.
Thank you for the tip on the tutorial!
But maybe you must learn firstly how create UV Map of your model and how create good topology.
I know how to create UV maps and I mentioned topology a great deal in my post When I do the squares thingy it looks even, not stretched and roughly the same size. I know how to unwrap and reasonably apply a texture, I’m struggling with creation of such texture…
Or you can use free or paid pre-made materials like VMATS, but even so you must learn a little optical physics for create custom materials.
I’d like to avoid using pre-made materials, I’d like to create it from scratch
I’m a programmer. And I learned shading when I wrote HLSL shader. If you want learn realistic shader creation, this is hard and time consuming work. But you never only read or watch Blender tutorials, look another programs, like Vray, Corona, Arnold, Renderman, Unreal Engine, Unity etc. And if you know shader programming, look shader creation tutorials. Example, I learned some things from documentations of FarCry or Uncharted game engine technical documents.
Shading is not that difficult. But it requires a different type of logic from optics.
Basically, you just create and use equations that produce a value from some variables (most of what you can find in the ‘Input’ nodes).
If you want to understand better what’s going on, i recomend you to read ‘TheBookOfShaders’. Despite the fact that it’s mainly oriented to GLSL, the logic is the same as in Blender.
A good fraction of the people you’re watching don’t know any more than you do. They sat down and experimented and said, “That looks like marble!” and then they recreated it with screen capture on and made a tutorial how to make marble. They don’t know why either. You can see this every time they use a color ramp to modulate a non-color value. That’s your clue that they’re just trial-and-erroring it same as you.
If you’re a physics grad student, then you ought to be pretty comfortable with math. That’s all that a material is. It is a function with certain inputs and certain outputs. And each individual node is a function with certain inputs and certain outputs.
Like, what’s a wave texture? Basically, you take your input coordinates, rotate them in the Z axis 45 degrees, take sin(x), then remap from (-1,1) to (0,1). That’s all.
I find that thinking of things in terms of math makes things much, much easier. I can understand that some people might find math intimidating. Hopefully, you don’t.
So the first step after deciding, “I want wood,” is to figure out what wood looks like. Mathematically. Well, there are bands of different density. How can I get that density? Maybe sin(x). What should I do with that density? Well, maybe I should use it to interpolate between two different RGB colors. How should I interpolate? Well, let’s just interpolate linearly using RGB channel values. So what we have here is a wave texture->mixRGB/mix.
So then, there are techniques that people use, even if they don’t know that they’re using them. They distort their coordinate space. They use interference between multiple lookups at different coordinates. (You could make any shape with just sine wave interference, right? Just need a lot of carefully chosen sine waves…)
This is a very basic technique that you should look up, and if you really can’t find anything, you should ask in another thread. (I’ve answered it enough times to meet my lifetime quota though.)
Like, I get the masks and black/white stuff with a layer of texture, but I struggle with creating “nice looking” stains/ streaks/drops/spills etc. People be like “just use this set of brushes” (I click and it costs money) or “use a tablet, it’s much better for painting” but I guess nothing is really free…
Got a smart phone? Take a photograph.
Like, I get the masks and black/white stuff with a layer of texture, but I struggle with creating “nice looking” stains/ streaks/drops/spills etc.
Welp, one thing to do is just stop watching tutorials pointlessly and start giving yourself some practices in actually observing how real-world materials work and then use your understandings of shading and try to implement those into the shading world creation… Spend some more time creating, fiddling around and you’ll start to develop your own logical shading base system by yourself and you’ll understand how to manipulate 0-1 values combined with textures to create certain looks, shapes, variables, etc…And if you spend enough time develop something to yourself, you’ll start to have your own routines and you’ll be able to see that the entire process of creating textures is just a bunch of repeating patterns all over again, it might seem challenging at first but again, it ain’t no rocket science we’re talking here :))
Okay, I decided to JUST EXPERIMENT. IE take every relevant-sounding node and any information I picked up from previously watched tutorials and fiddle with it until I get at least some feeling for what does what.
I came up with the following texture for a seat and I used a grayscale painted mask to create the sweaty effect (yes I looked up on Google how sweaty usually seats are. I feel pathetic because I probably have seen something like that hundreds of times, but paid little attention to it). I haven’t watched any tutorial, I just fiddled with wavy nodes, scaling and rotating them until the pattern was reached, and I used some mixing shaders to fit it all together. I also learned that the “bump” node plugged into “normal” doesn’t do anything, if the color node is plugged into “normal”, it has to be plugged into “height”…weird.
I wanted to make the pattern so that it criss-crosses itself but I guess this can only be done with real image textures from an actual photo of a piece of cloth? Anyway, here goes nothing…not the best looking thing, but it’s a start.
That’s pretty good! I have spent a lot of time trying to figure out nodes, right from when I jumped from BI to Cycles. It took a lot of trial and error, and a lot of research and practice, but I got to the point where I feel ok making a fair bit of procedural textures.
One thing that was hugely helpful was participating in Nodevember last year. I didn’t catch 'em all, but I did most days. Here is a link to my process thread, where I tried to document my learning process a bit: SR Nodevember prompts
Those are BEAUTIFUL <3
The biggest tip I have for grasping the concept is keeping the flow of your data types as simple as possible. It’s much better to mix colors, rather than mix shaders, for example. Try to keep the data type flows together, to remember what you are working on.
And always do a refinement pass. Make sure that all the nodes that need to be there are there and that there are no extras. I often catch myself adding many adjustment factors along the way, then I look back and see I have 4 multiply nodes in this chain and I can reduce that down to one node.
Have fun learning, it’s a super satisfying skill to have. Feel free to DM me if you have any questions.
follow along tutorials from syncretic 3d might help for getting realistic results they were the thing that really got me to understand nodes. also I quite like the mix rgb node set to multiply when trying to combine various noises musgrave etc
you could save advanced nodegroups and maths heavy nodegroups in categorized folders on your computer then append them into any scene (thats what i do)
collect some starting points from nodevember on twitter there are thousands of posts from other people many who are very professional!
gumroad and blendswap also has lots of materials you can pull apart and study
if you like nodes tutorials with lots of math Erindale on youtube is pretty good
You shouldn’t feel pathetic. You should be doing this all the time, everytime.
Try to model a face sometime, if you haven’t already. Out of all the things you’ve been paying attention to during your life, faces probably top the list, right? So you know what they look like? Lol, no. So incredibly no. That’s not how it works.
Also, if you’re doing math, separate it so that it makes sense to read later rather than optimizing it for minimum amount of nodes. I.e. you might consider n2pi in one node, remap it to 0-1, then add 1 if you want a logarithm of a trigonometric function. Coming back later, if all you saw was n*somreallyweirdnumber, it would throw you off.
So, basically if you didn’t get at least a B- in highschool math you’re going to have a hard time? That would explain a lot.
I’d pay good money for a course that taught me math through blender rather than the other way around. CGMatter/DefaultCube started a shader course that looked like it would go down a path that would really help me but after a handful of very informative videos he didn’t make any more.
I had been trying for like a year to put a black-to-white-to-black gradient+color-ramp on a rectangular plane that looked exactly like a similar gradient in photoshop and it was effing illogical and frustrating. I finally figured out a way to do it (that I understood rather than stumbling accidentally on a solution that I had no understanding of) but only after watching a stupid number of unrelated shading-related videos from LOTS of people over a very very long period of time. There seems to be no good youtube channel for this stuff. There is stringfairy/syncretic3d but at a certain point he makes a massive jump from using basic nodes to using a large collection of utility nodes he made from scratch.