The main advantage of SPDX license identifiers over the traditional
license headers is that it's more difficult to overlook inappropriate
licenses for kwin, for example GPL 3. We also don't have to copy a
lot of boilerplate text.
In order to create this change, I ran licensedigger -r -c from the
toplevel source directory.
The surface size is a logical size, which renders it unsuitable for
deciding whether the window pixmap needs to be discarded.
We need to discard window pixmaps when the buffer size changes. That
has a drawback though, discarding textures is kind of an overkill with
linux-dmabuf. However, fixing that would involve changes in kwayland
server that are far from being trivial.
BUG: 422459
The surface-to-buffer matrix provides a generic mechanism for mapping
things from the surface-local coordinate space to the buffer coordinate
space. If it changes, we know for sure that the texture coordinates
have to be re-computed.
Sub-surface contribute to the window quads cache. So, we must re-build
it, if any sub-surface has been changed.
Differential Revision: https://phabricator.kde.org/D29131
