Arbitrary scissor shapes?

[genericdave]

Alright, I know full well that löve only supports rectangular scissor buffers. What I'm wondering if there's any other way I could get an irregular viewport-like shape drawn to the screen. Could I, for example, draw to a framebuffer and then create an arbitrary shape that could clear part of that buffer and then flip that onto the screen buffer? Somehow, I get the feeling this is going to require me making a request on the issue tracker. Just wanted to check here first. Maybe I'm missing something.

I'm trying to emulate this kind of awesometastic splitscreening.

[Robin]

mapPixel could work, but that would be horribly, horribly slow.

[genericdave]

that would be horribly, horribly slow.

Yeah, that's basically what has me stumped here. Accessing image data directly is expensive. I don't think a reasonable implementation of this is possible with löve currently. I'm a bit surprised to find that Opengl restricts its scissors and viewports to rectangles as well. Looks like I would need some sort of clipping mask in order to achieve this.

[Robin]

Looks like I would need some sort of clipping mask in order to achieve this.

Think so, yeah. But it seems so unlovely to me.

[genericdave]

Clipping masks in general are unlovely? Or are you talking about specifically as a solution to this?

[Robin]

In general. Too low-level.

[genericdave]

Hmm, looks like löve might eventually be able to do this with simple blending modes. Like this. I could be dead wrong, however.

[TechnoCat]

Does love.graphics.rotate not affect scissor?.

UPDATE: My gosh, it doesn't!

[miko]

mapPixel could work, but that would be horribly, horribly slow.

How about ImageData:paste()? You could only split it horizontally or vertically, but still should be faster.

[Robin]

How would that be an improvement over using scissor?