Try a different angle for gradient

sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_1.png

diff --git a/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_1.png b/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_1.png
index 2a4fa3e..31178dc 100644
--- a/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_1.png
+++ b/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_1.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:465606f95a940c12b8c510bbcd8a8168450693a7908326a80bdc2887f918b4ae
-size 1388
+oid sha256:29b56c78edf877b6bb424b1ad3946b11e2331e8c937684bb1cc2afb8d904bc60
+size 1842

sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_2.png

diff --git a/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_2.png b/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_2.png
index 8cc46d3..7943a17 100644
--- a/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_2.png
+++ b/sparse_strips/vello_sparse_tests/snapshots/gradient_sweep_with_transform_rotate_2.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:2140e3abc8b5ab81d545906788cebf6cb21e4c66b52ae078040419d4904cb667
-size 1418
+oid sha256:12a07084d4865628fc827403a9709f5cae13adef7361cb64137b3a760b08889a
+size 1851

sparse_strips/vello_sparse_tests/tests/gradient.rs

diff --git a/sparse_strips/vello_sparse_tests/tests/gradient.rs b/sparse_strips/vello_sparse_tests/tests/gradient.rs
index 229dfcf..db6ecfa 100644
--- a/sparse_strips/vello_sparse_tests/tests/gradient.rs
+++ b/sparse_strips/vello_sparse_tests/tests/gradient.rs
@@ -967,7 +967,7 @@
     fn gradient_sweep_with_transform_rotate_1(ctx: &mut impl Renderer) {
         gradient_with_transform(
             ctx,
-            Affine::rotate_about(PI / 4.0, Point::new(50.0, 50.0)),
+            Affine::rotate_about(50.0f64.to_radians(), Point::new(50.0, 50.0)),
             25.0,
             25.0,
             75.0,
@@ -979,7 +979,7 @@
     fn gradient_sweep_with_transform_rotate_2(ctx: &mut impl Renderer) {
         gradient_with_transform(
             ctx,
-            Affine::rotate_about(-PI / 4.0, Point::new(50.0, 50.0)),
+            Affine::rotate_about((-50.0f64).to_radians(), Point::new(50.0, 50.0)),
             25.0,
             25.0,
             75.0,