🐛 Fix wasm glitches

render-wasm/src/render/cache.rs

@@ -1,6 +1,18 @@
 use super::{Image, Viewbox};
+use skia::Contains;
+use skia_safe as skia;
 
 pub(crate) struct CachedSurfaceImage {
     pub image: Image,
     pub viewbox: Viewbox,
+    pub invalid: bool,
+    pub has_all_shapes: bool,
+}
+
+impl CachedSurfaceImage {
+    pub fn invalidate_if_dirty(&mut self, viewbox: &Viewbox) {
+        if !self.has_all_shapes && !self.viewbox.area.contains(viewbox.area) {
+            self.invalid = true;
+        }
+    }
 }