Hey samzyann,
I use the Smart UV Project most of the time; but I occasionally run into issues with seams and stretching.
Try to learn unwrapping by setting seams and then using one of the algorithms. Angle based or conformal. It is so much better in any way. Especially when it comes to distortions. That’s what these algorithms are made for. To distribute the mesh across the 2d surface of a texture as distortionfree as possible.
For texturing; I have been primarily using procedural textures available in Bforartists. While these are great; I feel that my textures often lack the realism I am aiming for.
Finally; I render the scenes using Cycles.
So you use procedural materials mainly if i understand you right. What you may need is 2D textures. Texturing is a very special and highly detailed chapter. Lots to learn. And i would unfortunately not recommend to do it in Blender or Bforartists. I’m an old man, i learned it the old traditional way with Gimp in pure 2d. You export the UV wire as a texture to have a mask for creating the textures for, and then you start to paint, layer image parts together, and so on. Nowadays it is mainly done in 3d by directly painting at the model. And as told, Blender / Bforartists is weak at it. There are addons where you can layer textures for painting, but in general the texture painting abilities are simply not good enough.
The industry solution is Substances by Adobe. Everything but cheap. But the king. There is more than the Substance painter. Substances is a whole material system which then can be used in game engines like Unreal or Unity for example. https://www.adobe.com/products/substance3d/apps/painter.html
The makers of 3d coat offers its painting module as an extra painting solution. Which is also great. https://pilgway.com/product/3dcoattextura
Armorpaint is a cheaper 3d texture painting s0lution. But costs also money nowadays, despite being open source. The code can still be found at Github, but it is obfuscated how to compile. https://armorpaint.org/download
The quixel mixer from Epic is free, and gives already lots of possibilities. https://quixel.com/mixer
Or, as told, go the traditional way and paint your textures in Photoshop, Gimp, Krita, Affinity Photo etc.
And then there is the artistic side. A realistic texture is made of so much small things and details that adds to the realistic look. Corners collects dirt for example. Or edges can look worn. Or leaking, scratches and dirt. And for that you need good base images that you can mix together to create your texture.
Texture pages like textures.com has great base images for this purpose. https://www.textures.com/search?q=leaking
There are also 3d material pages like CGAxis https://cgaxis.com/
I hope that helps a bit 🙂
Kind regards Reiner
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