custom texture patterns?

Hi. I’ve searched the web, but anything with the words ‘procedural’ or ‘texture’ just leads to existing ones in Blender.
Are there any custom-made patterns available? (probably implemented with a Script Node)
(might be OSL but that is not desired)
thanks

The answer is yes.
There are plenty of examples scattered in the forum and even more to be created, and if you want to look up for OSL scripts, the Shane Ambler’s github has plenty of examples.

thanks for the reply.
I do not want an OSL script because FAIK those make shaders (and can’t use GPU). I would just like a python script I can stick in a node as a pattern usable in my node materials.
Can you provide one example? I did not find anything trying to do a search that did not lead to only information about using built-in Blender proc textures.
thanks
(btw, I am specifically interested in just 2D or 3D math textures I would use to create a material, not anything with meshes, particles, etc)

There are plenty of threads…
for example:

https://blenderartists.org/forum/showthread.php?346786-Procedural-Patterns-What-is-possible

just to name a few

The logic to make patterns with nodes, python or osl is more or less the same. If you want to learn about making new patterns, osl is a good start, even if you ain’t going to use it.
Note that there are some stuff from osl that you don’t have with nodes, and for GPU rendering you are limited to what the original nodes can offer, but the principle is there: How to make a point at some coordinate have this or that color.

More to read here: http://thebookofshaders.com

If you want, you can write your own nodes; but you’ll still have to use the nodetree class (similar to a nodegroup), so that Cycles can understand it. This means asking for a new shadertree from bpy.data.node_groups, populate it with sockets, nodes, and links, and define the layout and custom properties.
To this extend, I’m developing some tools for creation of new nodes, and LazyDodo is writing a script that convert some osl scripts to nodetrees. There has been some progress, and the functionality is already there; thought i doubt it will be ready for 2.79.