broken ColorTest with cpu rendering about egui_skia HOT 4 OPEN

diff --git a/src/painter.rs b/src/painter.rs
index 5c07f5b..8696332 100644
--- a/src/painter.rs
+++ b/src/painter.rs
@@ -205,11 +205,19 @@ impl Painter {
 
                             pos.push(Point::new(fixed_pos.x, fixed_pos.y));
                             texs.push(Point::new(v.uv.x, v.uv.y));
+
+                            let c = v.color;
+                            let c = Color::from_argb(c.a(), c.r(), c.g(), c.b());
+                            // un-premultply color
+                            let mut cf = skia_safe::Color4f::from(c);
+                            cf.r /= cf.a;
+                            cf.g /= cf.a;
+                            cf.b /= cf.a;
                             colors.push(Color::from_argb(
-                                v.color.a(),
-                                v.color.r(),
-                                v.color.g(),
-                                v.color.b(),
+                                c.a(),
+                                (cf.r * 255.0) as u8,
+                                (cf.g * 255.0) as u8,
+                                (cf.b * 255.0) as u8,
                             ));
                         });