Add viewport value blocks

[manuq]

To integer blocks for the viewport width and height. And one Vecto2 block for the viewport center.

[manuq]

Can be used like this:

[wnbaum]

Definitely good to have some sort of blocks like these!

One issue I can think of is that the viewport width, height, and center are all in viewport pixel coordinates, not in our 2D scene coordinates. So when we get the viewport center, it is not the same as the 2D scene center that our camera is fixed on. We might want to add some extra conversion there.

[wnbaum]

Here's some suggestions that I forgot to add to the other review!

[manuq]

Definitely good to have some sort of blocks like these!

One issue I can think of is that the viewport width, height, and center are all in viewport pixel coordinates, not in our 2D scene coordinates. So when we get the viewport center, it is not the same as the 2D scene center that our camera is fixed on. We might want to add some extra conversion there.

Yes, this seems to be the convertion we need: https://forum.godotengine.org/t/how-do-i-get-the-center-of-the-screen-without-using-camera/20545/3?u=manuq

In the current architecture we can't do that easily. I managed to do it with lambda functions. The code looks bad but it works in Pong to reset the ball. See the fixup commit.

I also appended another commit to construct a Vector2 from X, Y float parameters. So these 2 are equivalent:

[wnbaum]

Working as expected! Code looks good to me. The generated code with the lambdas is definitely ugly, but that's something to figure out in another PR.