procedural texture filter equations / functions

[NotMyFault]

Hi,

 

looking for a more in depth documentation about functions in procedural texture and equations filters.

The table in the help file provides mostly the names and parameter list, lacking more detailed definition.

Using the forum seach, help search, and finally google to find more did not revale useful results, as names are often generic and used in other contexts, e.g. try tocui

https://affinity.help/photo/en-US.lproj/index.html?page=pages/Filters/filter_equations.html?title=Equations

Here are my questions:

1. Where can i find the complete definition of the functions?
2. Where can i find a complete list of "persistent variables" like h,w, R,G,B,A, I, x,y ?
3. The scope where these variables exist, e.g. color format like RGB / GRAY / LAB, equations or procedural text filter, ...

Thank you in advance.

[stokerg]

Hi @NotMyFault,

Sorry for the delay in a reply here.  We are currently working through a backlog of tickets.

As for this, we do have a bit more documentation here and that's it really. 

Sadly these type of questions are beyond the scope of Technical Support we can offer and i suspect you know a lot more on this topic than most of us in Tech Support.  I'm sure if anyone else has any information they can share, they will do, once they see this reply  

 

[GarryP]

16 minutes ago, stokerg said:

Sadly these type of questions are beyond the scope of Technical Support we can offer and i suspect you know a lot more on this topic than most of us in Tech Support.

Sorry, but did I read this correctly?
Are you saying that the Serif staff don’t know how their own software works?
Or are you saying that the developers won’t tell technical support how the software works?
Or something else?
I’m confused.

This sounds a little like the following conversation:
Company: “Thank you for purchasing our chainsaw. Please make sure you don’t hold it at the wrong end.”
Customer: “Which end is the wrong end?”
Company: “I dunno, but switch it on and you will soon find out.”

[Chris B]

Technical Support are here to offer general guidance and support with the software. 

We have provided our customers with an extensive list of functions which can be seen in the link Gareth posted above which is already an expansion on what NotMyFault linked to.

A lot of the Procedural Texture functions are direct mappings of common math functions in C/C++ etc. so the user to effectively make use of the PT filter would need some knowledge in this area.

[NotMyFault]

1 hour ago, Chris B said:

A lot of the Procedural Texture functions are direct mappings of common math functions in C/C++ etc. so the user to effectively make use of the PT filter would need some knowledge in this area.

Would it be possible to get a link where we can find more about these common math functions? Which exact libraries? Maybe a book ? 
I have a computer science background and main source of income in software development from 1980-2000, and would be excited to dig deeper, unfortunately i could not find any good results pointing to specific  c/c++ libraries using google. 
 

The help files list only names and parameters, but in most cases do not explain

The actual function, 

e.g. debump, 

the type of result (S, T, vector,)

the numerical ranges of return values ( normalized / capped to 0..1 or not)

the way to access individual elements of vectors (found .x .y .z / .R .G .B), but what in case of >3?

A complete list of reserved names (like pi, gr, …)

 

[NotMyFault]

Bump