Add Servo site compatibility frame smoke

crates/ely_servo_host/src/host.rs

@@ -11,6 +11,118 @@ pub enum WebViewState {
     Crashed,
 }
 
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct RenderedFrameSummary {
+    width: u32,
+    height: u32,
+    opaque_pixel_count: u64,
+    non_white_pixel_count: u64,
+    sample_hash: u64,
+}
+
+impl RenderedFrameSummary {
+    #[must_use]
+    pub fn from_rgba_bytes(width: u32, height: u32, rgba_bytes: &[u8]) -> Self {
+        let mut opaque_pixel_count = 0;
+        let mut non_white_pixel_count = 0;
+        let mut sample_hash = 0xcbf29ce484222325_u64;
+
+        for (index, pixel) in rgba_bytes.chunks_exact(4).enumerate() {
+            let [red, green, blue, alpha] = [pixel[0], pixel[1], pixel[2], pixel[3]];
+            if alpha > 0 {
+                opaque_pixel_count += 1;
+            }
+            if alpha > 0 && (red < 245 || green < 245 || blue < 245) {
+                non_white_pixel_count += 1;
+            }
+            if index % 97 == 0 {
+                for byte in pixel {
+                    sample_hash ^= u64::from(*byte);
+                    sample_hash = sample_hash.wrapping_mul(0x100000001b3);
+                }
+            }
+        }
+
+        Self { width, height, opaque_pixel_count, non_white_pixel_count, sample_hash }
+    }
+
+    #[must_use]
+    pub fn width(&self) -> u32 {
+        self.width
+    }
+
+    #[must_use]
+    pub fn height(&self) -> u32 {
+        self.height
+    }
+
+    #[must_use]
+    pub fn opaque_pixel_count(&self) -> u64 {
+        self.opaque_pixel_count
+    }
+
+    #[must_use]
+    pub fn non_white_pixel_count(&self) -> u64 {
+        self.non_white_pixel_count
+    }
+
+    #[must_use]
+    pub fn sample_hash(&self) -> u64 {
+        self.sample_hash
+    }
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct RenderedFrame {
+    width: u32,
+    height: u32,
+    rgba_bytes: Vec<u8>,
+    summary: RenderedFrameSummary,
+}
+
+impl RenderedFrame {
+    #[must_use]
+    pub fn from_rgba_bytes(width: u32, height: u32, rgba_bytes: Vec<u8>) -> Self {
+        let summary = RenderedFrameSummary::from_rgba_bytes(width, height, &rgba_bytes);
+        Self { width, height, rgba_bytes, summary }
+    }
+
+    #[must_use]
+    pub fn width(&self) -> u32 {
+        self.width
+    }
+
+    #[must_use]
+    pub fn height(&self) -> u32 {
+        self.height
+    }
+
+    #[must_use]
+    pub fn rgba_bytes(&self) -> &[u8] {
+        &self.rgba_bytes
+    }
+
+    #[must_use]
+    pub fn summary(&self) -> &RenderedFrameSummary {
+        &self.summary
+    }
+
+    #[must_use]
+    pub fn opaque_pixel_count(&self) -> u64 {
+        self.summary.opaque_pixel_count()
+    }
+
+    #[must_use]
+    pub fn non_white_pixel_count(&self) -> u64 {
+        self.summary.non_white_pixel_count()
+    }
+
+    #[must_use]
+    pub fn sample_hash(&self) -> u64 {
+        self.summary.sample_hash()
+    }
+}
+
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct WebViewSnapshot {
     webview_id: WebViewId,
@@ -116,4 +228,6 @@ pub trait ServoHost {
     fn tick(&mut self) -> bool;
 
     fn paint(&mut self, webview_id: &WebViewId) -> Result<(), ServoHostError>;
+
+    fn last_rendered_frame(&self) -> Result<RenderedFrame, ServoHostError>;
 }