I have a basic question which I don't know how to look up an answer because I don't know what various operations are called. I am very new to Inkscape and I have a basic understanding of gimp. Can you give me a general sense of what tasks are involved and the order they need to be performed in. I am a very superficial understanding of layers and paths, though I haven't really used these things when making images.

I have a bitmap image template (IMAGE 1) with an interior half circle. http://i.stack.imgur.com/dZvsg.png

I need to insert a smaller half-circle image (IMAGE 2) inside the blank half-circle in the template. http://i.stack.imgur.com/53VtT.png

IMAGE 1 needs to be superimposed over the smaller half-circle image so that IMAGE 1 is "higher". The reason is that the interior bitmaps don't correspond exactly in shape to the empty half-circle. Plus, I'm using the metaphor of the window here, so you would expect that the view of outside to be obstructed by the window.

I'm assuming that I need to somehow remove the half circle from IMAGE 1 first. Can you confirm? If yes, what is this task called?

One other thing. At some point I will trace the bitmap to IMAGE 1 in order to convert it to vector image. However, in the final SVG, image2 will remain a bitmap which will be linked to it (Indeed, I will be making several different outputs using the original IMAGE 1 template and different interior images).

If I need to remove the interior half-circle, is it better to do it in gimp before importing?

If I understand correctly, you would like the line-art converted to vector and the other element(s) to remain bitmap (or raster).
If they overlap, the vector art would be in the foreground. That can be done with layers or z-order (stacking).

If you are converting the line-art to vector, you probably won't need to cut a hole in it for background elements to show, it will have paths and no background... so, that begs the question: what will be the background behind both elements?... the page color, or another object?

Sorry for the delay in responding. Other things plus I was trying to research the question.

I could easily create an object which provides background color -- white.

What I want to do is to adjust the interior image so that it completely covers the blank semi-circle in the middle.



I think it would be worth it to still carve out the empty space in the middle to allow this.

But that assumes that I can specify the irregular shape to carve it out properly. How do you describe the task to do this?

Thanks.

The images are already cutouts (they have alpha-channels to hide their backgrounds), so it is simple enough to import them into Inkscape and align them. If you import the interior first, it will be lower in the z-order and the line art will cover any overlap (but z-order is simple enough to re-arrange). http://tavmjong.free.fr/INKSCAPE/MANUAL ... Order.html

A bigger task will be to convert the line-art to svg, but given enough time the strokes can be traced.