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I've got lots!
Here's a thread for it
Here's a thread for it
1. Tech art really benefits from procedural generation. Play with maths and procgen so you can learn the building blocks
2. You can learn building blocks with tools like UE4 material editor (unlit materials), shaderforge, and texture gen tools like Filter Forge
3. Three types of values you have in a shader are:
- from your mesh
- from a texture
- from maths
You'll want to combine & chain these
- from your mesh
- from a texture
- from maths
You'll want to combine & chain these
4. Be familiar with the values your shaders can access: the XYZ positions of vertices and normals, the texture UV coords, and anyth custom
5. RGB is XYZ. You can convert between colours and positions back and forth, and it's often useful to. Likewise RG is UV for texture samples
6. get ok with core vector math. (Could do whole thread on it!) Add, subtract, dot and cross, and space xform, get length, normalise
7. But especially dot product is your friend. It's core for lighting. Dot of two normal vectors tells you whether they're facing same way
8. If dot product is >0, they're facing similar direction (less than 90 degrees). <0 is facing away. Zero means they're orthogonal/perpendic
9. If two vecs are normalised, tho, the range is -1 .. 1. If you clamp this to 0-1, bam you've got Lambert shading
10. if you take a dot product and threshold it with an if statement or step fn, you get "toon" shading - either lit or dark, but no blend
11. OR you can use a dot product for a texture lookup! That lets you use texture art to define how lighting affects a surface colour
12a. Also this
12b. Post processing can do this, and often in engines other meshes can read from the previously drawn frame! Deferred engine rely on it too
