What do framebuffers DO?

[Taehl]

Can I, for instance, render some stuff to a framebuffer, then manipulate them? Say, render them with a mask? That'd be handy. If not, then what, exactly, is the point of using a framebuffer instead of just drawing stuff (or drawing stuff to a spritebatch)?

[Robin]

If not, then what, exactly, is the point of using a framebuffer instead of just drawing stuff (or drawing stuff to a spritebatch)?

A SpriteBatch is a very different beast. They are useful for things like tile sets.

To a Framebuffer, you can draw anything you can draw to screen as well. What's nice is that you only have to draw this once -- which I use in AStrat, where the the map is created by drawing pixels (rectangles, actually), which would be excruciatingly slow if not for Framebuffers. And that's just the beginning.

[Mud]

which I use in AStrat

<ot>What's that?</ot>

[Taehl]

It's a fractal animation he made which crashes after ten seconds.

So, the only difference between using a framebuffer and drawing directly to the screen is that framebuffers aren't cleared after every frame?

[Robin]

which I use in AStrat

<ot>What's that?</ot>

This:

astrat.love

Requires 0.7.0, obviously

(2.11 KiB) Downloaded 128 times

And it doesn't crash any more, btw.

So, the only difference between using a framebuffer and drawing directly to the screen is that framebuffers aren't cleared after every frame?

If you mean what I think you mean, then yes. They are very, very useful. I use Framebuffers in RichText as well.

[Taehl]

Okay, so, does Love have any way of letting me get at OpenGL's fragment shaders?

[vrld]

Can I, for instance, render some stuff to a framebuffer, then manipulate them? Say, render them with a mask?

With the current blendmodes it is difficult. You can use the subtractive mode to have something like an inverse stencil/hole puncher:
1. Paint with alpha 255 (and possibly the color white) what you don't want to have on the screen to a framebuffer.
2. Paint something to the screen.
3. Set blendmode to subtractive.
4. Paint framebuffer.
5. ???
6. Profit.

Okay, so, does Love have any way of letting me get at OpenGL's fragment shaders?

Not yet, but if you can build love from source there is love-glsl. There is also a feature request.
If you need help using it, just can just PM me

[thelinx]

which I use in AStrat

<ot>What's that?</ot>

This:

astrat.love

And it doesn't crash any more, btw.

a-awesome

(an hour later)

best waste of an hour ever

[zac352]

So, the only difference between using a framebuffer and drawing directly to the screen is that framebuffers aren't cleared after every frame?

Clearing the screen is done with love.graphics.clear() and love.graphics.present(). They are called from the default love.run function. The default love.run function does not draw/clear framebuffers.

[Robin]

a-awesome

(an hour later)

best waste of an hour ever

Thanks. I want to get the different nations to attack each other, but I have no idea how to do that in a way that doesn't look awful as of yet.