1 files changed, 99 insertions, 0 deletions
diff --git a/gfx/wr/examples/iframe.rs b/gfx/wr/examples/iframe.rs
new file mode 100644
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+++ b/gfx/wr/examples/iframe.rs
@@ -0,0 +1,99 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+extern crate gleam;
+extern crate glutin;
+extern crate webrender;
+extern crate winit;
+
+#[path = "common/boilerplate.rs"]
+mod boilerplate;
+
+use crate::boilerplate::{Example, HandyDandyRectBuilder};
+use webrender::api::*;
+use webrender::render_api::*;
+use webrender::api::units::*;
+
+// This example uses the push_iframe API to nest a second pipeline's displaylist
+// inside the root pipeline's display list. When it works, a green square is
+// shown. If it fails, a red square is shown.
+
+struct App {}
+
+impl Example for App {
+    fn render(
+        &mut self,
+        api: &mut RenderApi,
+        builder: &mut DisplayListBuilder,
+        _txn: &mut Transaction,
+        _device_size: DeviceIntSize,
+        pipeline_id: PipelineId,
+        document_id: DocumentId,
+    ) {
+        // All the sub_* things are for the nested pipeline
+        let sub_size = DeviceIntSize::new(100, 100);
+        let sub_bounds = (0, 0).to(sub_size.width as i32, sub_size.height as i32);
+
+        let sub_pipeline_id = PipelineId(pipeline_id.0, 42);
+        let mut sub_builder = DisplayListBuilder::new(sub_pipeline_id);
+        let mut space_and_clip = SpaceAndClipInfo::root_scroll(pipeline_id);
+        sub_builder.begin();
+
+        sub_builder.push_simple_stacking_context(
+            sub_bounds.min,
+            space_and_clip.spatial_id,
+            PrimitiveFlags::IS_BACKFACE_VISIBLE,
+        );
+
+        // green rect visible == success
+        sub_builder.push_rect(
+            &CommonItemProperties::new(sub_bounds, space_and_clip),
+            sub_bounds,
+            ColorF::new(0.0, 1.0, 0.0, 1.0)
+        );
+        sub_builder.pop_stacking_context();
+
+        let mut txn = Transaction::new();
+        txn.set_display_list(
+            Epoch(0),
+            sub_builder.end(),
+        );
+        api.send_transaction(document_id, txn);
+
+        space_and_clip.spatial_id = builder.push_reference_frame(
+            sub_bounds.min,
+            space_and_clip.spatial_id,
+            TransformStyle::Flat,
+            PropertyBinding::Binding(PropertyBindingKey::new(42), LayoutTransform::identity()),
+            ReferenceFrameKind::Transform {
+                is_2d_scale_translation: false,
+                should_snap: false,
+                paired_with_perspective: false,
+            },
+            SpatialTreeItemKey::new(0, 0),
+        );
+
+        // And this is for the root pipeline
+        builder.push_simple_stacking_context(
+            sub_bounds.min,
+            space_and_clip.spatial_id,
+            PrimitiveFlags::IS_BACKFACE_VISIBLE,
+        );
+
+        // red rect under the iframe: if this is visible, things have gone wrong
+        builder.push_rect(
+            &CommonItemProperties::new(sub_bounds, space_and_clip),
+            sub_bounds,
+            ColorF::new(1.0, 0.0, 0.0, 1.0)
+        );
+        builder.push_iframe(sub_bounds, sub_bounds, &space_and_clip, sub_pipeline_id, false);
+        builder.pop_stacking_context();
+        builder.pop_reference_frame();
+    }
+}
+
+fn main() {
+    let mut app = App {};
+    boilerplate::main_wrapper(&mut app, None);
+}