Screen filters in Ren'Py?

[Greeny]

So, I was thinking about screen filters. You know, those things where your entire screen goes black-and-white or such.
Is there already a way to do this in Ren'Py, aside from applying the desired filter to every individual image?
And, if not, would it be worthwhile to implement this feature in a future release?

[Aleema]

You can make a transparent full-screen image of a solid color, and then show it. Like, a dark purple slide that's transparent might make everything look like night.

[Greeny]

You can't show it over your menus and textboxes, I believe (not sure). Would work, but it's not very elegant. Also, this provides no method for b/w. More than overlays this would be useful for filters that affect the image itself.

I don't think it would be too hard to implement as a new feature, and I think it would be worthwhile to implement a synthax for this, but that's what I'm putting up for discussion maybe something like:

Code: Select all

scene bg cheeseland with dissolve with black_and_white

That would make the filter affect the whole screen until the next scene statement.
or

Code: Select all

filter bloom
scene bg heaven with fade
"St. Peter" "Get outta here!"
filter none
scene bg hell with fade

Which would control some sort of internal filter class.
Something like that.

[PyTom]

Allow color modification is a direction that I'd like to take Ren'Py in, but there are some issues with it - it pretty much requires a shader-based video card to get good performance at this. (So a card that supports OpenGL 2.)

It's one of those things where the situation improves the more one waits, as obsolete video cards are eventually replaced.