Mirrors/servo
1
0
Fork 0
mirror of https://github.com/servo/servo.git synced 2025-06-22 08:08:59 +01:00
Code Issues Projects Releases Packages Wiki Activity

Fix the identity transform of rotatex and rotatey.

Browse source 
Let's see the example: "rotatex(360deg)" to "none".

While we do interpolation between "rotatex" and "none", the original code
path is:
1. Build an identity transform for none and always use (0, 0, 1) as the
   direction vector, i.e. Rotate(0, 0, 1, 0deg).
2. Do interpolation between rotatex (i.e. Rotate(1, 0, 0, 360deg)) and
   Rotate(0, 0, 1, 0deg). Because their direction vectors are different,
   so we do matrix decomposition/interpolation/recomposition on both
   functions. The problem is, matrix decomposition makes the 360deg
   disappear, so it looks like "rotatex(0deg)".
3. Obviously, we are trying to interpolate from rotatex(0deg) to none, so
   the interpolated matrix is always an identity matrix.

I think rotatex, rotatey, and rotatez are special cases which should
really rotate according to the angle, so we should build the identity
transform for them according to the normalized direction vector, and so we do
interpolation on the angle, instead of converting them into matrix.

Replacing build_identity_transform_list() with
add_weighted_transform_lists(list, list, 0, 0) might be another solution;
However, I didn't do that because build_identity_transform_list() is
much simpler.
This commit is contained in:
Boris Chiou 2017-08-16 11:20:09 +08:00
parent 03cf0a8cb8
commit 4ed1a6be20
1 changed files with 3 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

5
components/style/properties/helpers/animated_properties.mako.rs
View file

@ -1340,8 +1340,9 @@ fn build_identity_transform_list(list: &[TransformOperation]) -> Vec<TransformOp
TransformOperation::Scale(..) => {
result.push(TransformOperation::Scale(1.0, 1.0, 1.0));
}
TransformOperation::Rotate(..) => {
result.push(TransformOperation::Rotate(0.0, 0.0, 1.0, Angle::zero()));
TransformOperation::Rotate(x, y, z, a) => {
let (x, y, z, _) = get_normalized_vector_and_angle(x, y, z, a);
result.push(TransformOperation::Rotate(x, y, z, Angle::zero()));
}
TransformOperation::Perspective(..) |
TransformOperation::AccumulateMatrix { .. } |