[Gimp-user] FIx for Overlay mode: done

[Alexandre Prokoudine <alexandre prokoudine gmail com>]

Dear users,

We've known for a while that GIMP's Overlay blending mode was
incorrect and identical to Soft Light mode. Now that OpenRaster file
format is becoming popular in free/libre workflows, this started
hurting actual users, so last week based on initial analysis by Paul
Geraskin, Michael Natterer fixed this for good in the unstable
(master) branch.

The new Overlay mode uses the respective formula from PDF and W3C
(SVG) specifications and thus should be identical to Photoshop's and
OpenRaster's Overlay mode. The PSD and ORA loaders/savers have been
fixed accordingly.

When opening (now) legacy XCF files, GIMP will automatically map the
old Overlay to Soft Light during compositing, so the rendering of your
old works will be preserved. For all newly created layers with Overlay
mode the new formula will be used instead.

Expect this to ship in unstable GIMP 2.9 first (soon), then in stable
2.10 (some time later).

Best regards,
Alexandre Prokoudine, on behalf of the GIMP team