dragonsfire wrote:
Okay I managed to get it moving. This is what I was missing before- the ellipse I created was not yet a path, as I had clicked on the wrong button- Selection to path as opposed to path to selection (I'm confused as to the distinction!?).
A "path" is just a set of instructions to draw virtual lines. Start here, get there, then over there.... To transform the path (scaling, rotation, translation...), the points are moved and the virtual lines are redrawn (so they are always perfect...).
A "selection" is a pixel-by-pixel indication of which pixels are selected. This pixel is in, this pixel is out, this pixel is partly in... This is representable as a grayscale image, where fully selected pixels are white, non selected pixels are black, and partly selected pixels are gray.
To go from path to selection, the path is "virtually" drawn and the pixel inside the path are marked selected. In the other direction, the border of the selection is computed (which is harder than it looks), and then a path is computed that follows that border.