When computing the distance between two filter functions, e.g.
HueRotate(0deg) and HueRotate(-360deg), we got an Err(()) and unwrap it
immediately in compute_filter_square_distance(), which causes a crash.
The root-cause is that we don't implement computed_distance of Angle, and we
assume we always get a valid result from compute_squared_distance() for
each filter function.
In the case where we accumulate transform:none onto decomposed matrix for
iteration composite whose iteration count is over 2, we pass zero
other_portion and self_portion which is over 1.0. We should care about the
case.
The concept of inherited style is about to get a bit more complicated, and this
will prevent consumers from doing it wrong.
Part 1 of Gecko bug1382806. r=emilio
While decomposing a 3D matrix, we should normalize the 2nd row right after the
Y scale computation. However, we accidentally use the length of the 1st row to
do the normalization. This causes the wrong Scale3D function while decomposing,
and then leads to the wrong decomposed 3D matrix.
Here, we correct it by using the right value (the length of the 2nd row).
r=hiro https://bugzilla.mozilla.org/show_bug.cgi?id=1381196
Store font-weight as integer directly
It doesn't make much sense to store `font-weight` as separate enums, especially given that we would need to support (somehow) arbitrary font weight value when we implement CSS Fonts Level 4.
This PR refactors the `font-weight` a bit to make it store as `u16` directly.
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We have to build an identity matrix while add_weighted() between
InterpolateMatrix and none transform in some cases, e.g. trigger a
transition from a mid-point of another transition to none.
If the units of two angles being interpolated/added matches, we should preserve
the original unit; otherwise, we fall back to radians. This matches the behavior
of Gecko.
Now we have AnimatableLonghand (to do with animatability) and
TransitionProperty (to do with transitionability), we should move
nscssproperty_id_is_animatable to be part of the former group.
Currently properties that are discretely animated cannot be
transitioned. Now that TransitionProperty should only be used for
transitions, we can redefine it to treat non-transitionable properties
as unsupported. This should allow us to simplify the code and make it
more self-documenting (e.g. making TransitionProperty actually relate to
transitions).
