When computing a transform value, there is nothing
to do, but we still need to copy the matrix from
src to dest, since it depends on the other transforms
in the array whether we are using the src or the
dest in the end.
This fixes cases like
-gtk-icon-transform: perspective(100px) matrix(1,2,...);
which would otherwise end up with a zero matrix.
When a css value has "child" css values (e.g. a linear gradient has
several color stop css values) which are all computed (won't change when
compute() is called on them), we want to skip computing the entire
subtree.
Since css values are immutable, we can set the is_computed flag at
construct time.
Since GtkCssValue instances are 0-initialized in _gtk_css_value_alloc,
the default for is_computed it FALSE. This commit only sets it to TRUE
in a few cases, such as various "none" singleton values which will never
change. Later commits will refine this and set it for more values.
This is just lots of renaming.
The interface remains private, so the public API does not change, apart
from removing the definition of the Interface object to avoid
subclassing.
Provide API to query the matrix instead of API that applies the matrix
directly. This makes the API more flexible.
See the commits implementing shadows.
The value implements the 2D parts of CSS transforms. See
http://www.w3.org/TR/css3-transforms/
For the specification.
All it does is give us an expressive way to define Cairo matrices (and
their transforms)
