More extension work.

TODO/_current.md

@@ -1,11 +1,3 @@
-# zero-ui-view
-
-* Implement renderer extension.
-    - Allow registering in view-process.
-    - Test it.
-        - Custom render item.
-        - Custom render update.
-
 # TextInput
 
 * Fix emoji segmenting, example: "🙎🏻‍♀️"
@@ -56,4 +48,13 @@
     - Implement `FallbackConfig::is_fallback(&ConfigKey) -> ReadOnlyArcVar<bool>`.
         - It uses the new modify tags to map from the key var to a bool?
     - Implement `FallbackConfigRef`, to work like the `EditableUiNodeList`.
-        - Implement `FallbackConfigRef::reset(ConfigKey)`.
+        - Implement `FallbackConfigRef::reset(ConfigKey)`.
+
+# zero-ui-view
+
+* Implement window extension.
+    - Access to raw handle and ability to spawn data that lives for the duration of the window.
+* Implement renderer extension.
+    - Affect renderer creation.
+    - Integrate with display item extensions.
+    - Implement use case, webrender blob renderer.

zero-ui-core/src/render.rs

@@ -1353,6 +1353,18 @@ impl FrameBuilder {
             .push_radial_gradient(PxRect::new(offset, bounds), gradient, &stops, bounds, PxSize::zero());
     }
 
+    /// Push a custom display extension context, call `render` and pop the item.
+    pub fn push_extension_context(&mut self, extension_key: usize, payload: ExtensionPayload, render: impl FnOnce(&mut Self)) {
+        self.display_list.push_extension(extension_key, payload);
+        render(self);
+        self.display_list.pop_extension(extension_key);
+    }
+
+    /// Push a custom display extension item.
+    pub fn push_extension_item(&mut self, extension_key: usize, payload: ExtensionPayload) {
+        self.display_list.push_extension(extension_key, payload);
+    }
+
     /// Create a new display list builder that can be built in parallel and merged back onto this list using [`parallel_fold`].
     ///
     /// Note that split list must be folded before any open reference frames, stacking contexts or clips are closed in this list.