Making a scrolling starfield in gimp?

So I saw this tutorial:

gimpusers.com/tutorials/starfield-tutorial

I know this isn't directly related to Construct2 but I was hoping to use this method to make a scrolling starfield. I must be barking up the wrong tree and was wondering if someone was here before. I figured I could just do something like the tutorial above, but they all require a black background... i think at some point I need a background that is transparent, alas I cannot build that noisy background with a transparent background. So I am stuck how does one build the graphics for a scrolling starfield? I realize there might be a dynamic way to do this in 'code' but thought I could just build some layers for the parallax...

Lots of layers with different parralax, that's all you need really...

yah but how to make the art, ideally i need a tile background with just a few dots (larger and smaller) for stars right?    mostly the background I pick should be transparent bg except for the stars themselves?

(at odds with this link here

gimpusers.com/tutorials/starfield-tutorial)

which requires the background to be black... so I guess can you make starfield as long as the bg is black, but then having multiple layers of it wouldn't be possible?

gimp plug

In theory, you can, since the background is all the same, just make some elements, group of stars here, gas cloud there, etc.

You can have it all on one layer. That with a tiled background with some stars on it.

Okay I think I got it by converting the black to alpha channel. the problem now is scrolling the layers. I have my main game layer with my objects... and then two more layers far back layer (with slow parallax) and a medium layer with a bit faster parallax. Problem is I am using a tiledBackground object for each, and I think its covering the other layer up (even though there is transparency. Not sure what I need to do or if this is the right away. I wanted larger stars to scroll past you faster than smaller ones to scroll past slower. Thinking I could have a png with large stars in it and transparent bg, on top of another png... Its like setting the layer color takes over and you cannot get a transparent channel there, even if you have a transparent png. is there something I am missing getting a full tiled background of a png with white stars and transparent everything else to show up over a background png thats transparent but whose layer is set to black?

I guess it is odd to me cause it seems like one layer covers up the other...regardless of the kind of tiled sprite thats over them?

I would set them to "Additive". Then you don't need to add alpha channels and you can get additional "glow" when they overlap eachother.

I have never used gimp, but to make the background tileable you need to offset the entire canvas by 50%, so if the background is 512x512, shift the entire image to the side 256 and up 256, and then remove the seams that appear after this shift. In photshop there is an "offset" filter, if you have to do it by hand, cut the image in half and swap it manually.

If it would help the forums, I can make a "creating simple tileable texture" tutorial.

ahhh so dont make it transparent and make it additive? i might of been missing that let me try that...

LOL that got it thanks man!