Re: [Gimp-docs] Layer new options

[Ell <ell_se yahoo com>]

> Hi all,
>
> I have an image with 2 layers and a background. In the context menu,
> the default Layer Composite Mode seems to be Auto. If I click on the
> other composite mode options, nothing happens. The same thing with
> Blend and Composite spaces.
>
> Are these options active? Is there anything else to do to active them?

Yes, they're all active, but their effect is highly dependent on the
actual layer content, so in some cases they may appear to do nothing.

We should definitely do a better job at explaining the function of the
new options, I know it's hard to write documentation for them right
now (not to mention that we have a general intention to tweak their UI,)
but the very short version is:

  - The composite mode controls which regions are preserved during alpha
    compositing (as per the layers' alpha values): regions belonging to
    the bottom layer (or, more precisely, the backdrop -- the
    combination of all the layers below the current one), the top
    layer, either of them (i.e., their union), or both of them (i.e.,
    their intersection).

  - The composite space controls the color space in which alpha
    compositing is performed (i.e., in which the colors are
    combined according to the alpha values).

  - The blend space controls the color space in which the colors are
    blended, as per the layer mode (e.g., the space in which the colors
    are added when using "Addition" mode).

Sorry for the late reply :)

--
Ell