"Poor man's fragment shader"

[HeroesGrave]

Suggested by BurntPizza. I apologise if this isn't what you meant in the first place, but this seems like a cool idea regardless.

Basically we take something like GLSL fragment shaders, and implement them as custom effects.

Simple:

Input: Pixel coordinates and optionally the old pixel colour Output: New pixel colour.

Then when the effect is applied, just iterate over all the pixels (or selected pixels if there is a selection), and send them to the 'fragment shader', which does operations and stuff and returns a new pixel colour.

More advanced:

Allow sampling from other pixels and multiple stages.

[HeroesGrave]

Maybe this could also be implemented as a tool.

[Longor1996]

Some notes on this: Make it an Image-Effect. It should only modify the selected layer (+selection).

I think a good name for this would be 'Pixel-Shader Effect'.

As for Scripting-Languages, have a list:

• Jhyton: I have to look up what this actually is :'D
• Jasic: A leightweight BASIC interpreter. Can build in commands for image editing pretty easely.
• Rhino/Nashorn: Easy to implement, fast, and its JavaScript, so people will know how to use it.
• Sandboxed Java: Not so easy, and would require the JDK 'tools'-lib or the ASM-lib.
• GLSL itself: This would be really (really) fast, and its actually pretty easy to do.

Also, the User has to be able to easely add in new scripts. Probably a small 'PixelShader Effect Manager' dialog that allows to add/remove/modify scripts?

Decisions, Decisions...

[HeroesGrave]

GLSL, or at least a simplified reimplementation of it.

[BurntPizza]

I was thinking probably just a custom DSL similar to GLSL, just the relevant bits. Real nice series of articles about DSLs and Java

So you guys think this should be a feature? I'll get started on it if so.

[HeroesGrave]

For 2.0, yes.

Probably time to make another milestone.

I also really need to get around to pushing out 1.0

[BurntPizza]

Cool, I'll probably make an 'experimental' branch or something on my fork, so it doesn't get mixed in with the regular dev

[HeroesGrave]

Sounds good to me.

[sylvia43]

We should make a basic version of this a top l and allow more complicated scrpts to be written.

[HeroesGrave]

The purpose of this is to allow 'scripted' effects, so someone with a small amount of programming knowledge could create custom effects without having to make a plugin.

[sylvia43]

Sorry about the previous comments... My idea is to do something like Photoshop... Have a relatively simple customizable shader with a ui, and allow for advanced shaders using a scripting language.

[HeroesGrave]

The point was to allow for powerful and customisable effects. I'm not sure if ease-of-use goes well with that.

Most simple effects will be eventually achieved through 'official' plugins.

[BurntPizza]

I agree with @HeroesGrave , I intended the shaders for custom stuff, applicable to the advanced users. That being said, if we eventually include a set of standard shaders with the program to augment the effects/plugins, so be it.

[sylvia43]

Ok I get it... So shader plugins are just going to be written in the shader language that we come up with then; and the core program doesn't need any.

[HeroesGrave]

They can but they don't have to be. Effects will still be able to be added through plugins.

[sylvia43]

Yeah but the plugins will basically be shader code snippets right?

[BurntPizza]

No. The plugins are more than just scripts. Take a look at the auto-updater plugin the @HeroesGrave has.

[sylvia43]

The plugins that add effects would be, in essence, shader code snippets right? Or do they just ignore the shader code and write their own?

[BurntPizza]

They could be, or they could be like the current built-in effects. Refer to heroesgrave/paint/effects