THIRD PARTY GEGL FILTER GUIDE

[contrast_]

https://github.com/LinuxBeaver/GUIDE-to ... GL-Filters
A full guide with the templates on how to make a third party GEGL filter is here.

The PDF guide (may be updated)!
https://cdn.discordapp.com/attachments/ ... _guide.pdf

Download to GEGL's source code and navigate to the folder Common. Study my template filter and difference-of-gaussians.c (which it is based on)
https://github.com/GNOME/gegl

VIdeo clip of my silly template filter in action
https://streamable.com/c3rwpo

The Template C file. (IT NEEDS TO BE IN ITS FOLDER TO COMPILE)

https://cdn.discordapp.com/attachments/ ... omfilter.c

Lasty, learn GEGL syntax in the GEGL threads here or at GEGL.org. Do not hesitate to ask me if you need help. Practice in GEGL Graph before you make a real filter.

[Pocholo]

Thank you contrast_

[contrast_]

Yes, the PDF just updated with information about downloading GEGL's source code.

[Pocholo]

I'll say it again; Thank you so much for all that information and you hard work. For letting your knowledge flow to us. What a great tutorial.

[Skinnyhouse]

Yes this has involved a colossal amont of work on your part contrast_. Hopefully I can find some time in the future to get my head around all of this.

[Rod]

Awesome. Now the fun begins!
Thank you.

[ofnuts]

"You do not need to be a C programmer".

You need to know the C syntax, you need to know how to compile the thing, you need to know how to understand errors and fix them.

I appreciate the effort, but so far it looks like "I cobbled some C code and eventually made it to work", and doesn't explain why or how things work. The only thing I learned from your example is that there is potentially a way to have one input and redirect it to several node inputs (on same node or on other nodes).

But looking at implementing this effect as a GEGL op, I'm still left with many questions: how do I apply vivid-light? How do I "scale" an input signal before I give it to a node input, and more generally how do I algebraically combine several inputs to make one input? how do I compile the code separately from the whole of GEGL (and other folks would also wonder where they put the compiled result without polluting the "official" GEGL code(*))?

(*) On Linux it's in ~/.local/share/gegl-0.4/plug-ins/ it seems

[Rod]

:lol "You do not need to be a C programmer".

You need to know the C syntax, you need to know how to compile the thing, you need to know how to understand errors and fix them.

I appreciate the effort, but so far it looks like "I cobbled some C code and eventually made it to work", and doesn't explain why or how things work. The only thing I learned from your example is that there is potentially a way to have one input and redirect it to several node inputs (on same node or on other nodes).

But looking at implementing this effect as a GEGL op, I'm still left with many questions: how do I apply vivid-light? How do I "scale" an input signal before I give it to a node input, and more generally how do I algebraically combine several inputs to make one input? how do I compile the code separately from the whole of GEGL (and other folks would also wonder where they put the compiled result without polluting the "official" GEGL code(*))?

(*) On Linux it's in ~/.local/share/gegl-0.4/plug-ins/ it seems

GEGL doesn't support layer modes?

[fatamorg84]

interesting information

[contrast_]

I just don't know how to make a proper guide. It all had to do with my luck of learning GEGL Syntax so I could use the graph to automate things back in mid 2021 to mid 2022. After that I started studying GEGL's source code and got lucky when it came to rearranging the nodes to make third party filters. I could record myself making a third party filter just to show everyone what I do.

[ofnuts]

I just don't know how to make a proper guide. It all had to do with my luck of learning GEGL Syntax so I could use the graph to automate things back in mid 2021 to mid 2022. After that I started studying GEGL's source code and got lucky when it came to rearranging the nodes to make third party filters. I could record myself making a third party filter just to show everyone what I do.

A manager of IT I worked for once said "I don't like luck because I'm not sure I can reproduce it".

[contrast_]

A better way to look at things is that if no one attempts to make a third party GEGL filter then no one really wants it bad enough. I have no background in computer science or C. I just got "lucky" by knowing GEGL Syntax in advance and figuring out how the C file is structured. Practice doing things in GEGL Graph first before you do anything.

[mahvin]

I'd rather be lucky than destined to fail. And even if I fail, courageous enough to keep on trying, whether luck plays a part or not.

[contrast_]

Consider this thread to be continued here.

viewtopic.php?f=9&t=20244

[contrast_]

If anyone wants to develop a GEGL Plugin don't hesitate to contact and ask me anything and I will guide you through it personally with baby steps if I have too. In Late June 2023 it will be the two year anniversary of the first GEGL Graphs I made.