From 5697d9ff2c1cfc831e1bc5c9c7c77502a87e2c68 Mon Sep 17 00:00:00 2001
From: Mike Blumenkrantz <zmike@osg.samsung.com>
Date: Tue, 19 May 2015 13:10:23 -0400
Subject: [PATCH] add back browser_host::composite() method for embedding

this changes the way that applications will use servo. whereas previously
it was only necessary to call initialize() -> makecurrent, it's now necessary
to explicitly call the composite() method in order to trigger the gl rendering.

any other composite attempts (by servo) will trigger the on_paint() method,
informing the app that a frame is ready. it's then up to the app to schedule
the composite() such that the frame is rendered in a timely manner
---
 ports/cef/browser_host.rs | 11 ++++++++++-
 ports/cef/window.rs       | 15 ++++++++++++---
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/ports/cef/browser_host.rs b/ports/cef/browser_host.rs
index b9112db85c9..680f7e8b99b 100644
--- a/ports/cef/browser_host.rs
+++ b/ports/cef/browser_host.rs
@@ -15,13 +15,15 @@ use geom::size::TypedSize2D;
 use libc::{c_double, c_int};
 use msg::constellation_msg::{self, KeyModifiers, KeyState};
 use script_traits::MouseButton;
-use std::cell::RefCell;
+use std::cell::{Cell, RefCell};
 
 pub struct ServoCefBrowserHost {
     /// A reference to the browser.
     pub browser: RefCell<Option<CefBrowser>>,
     /// A reference to the client.
     pub client: CefClient,
+    /// flag for return value of prepare_for_composite
+    pub composite_ok: Cell<bool>,
 }
 
 full_cef_class_impl! {
@@ -176,6 +178,12 @@ full_cef_class_impl! {
             this.downcast().send_window_event(WindowEvent::InitializeCompositing);
         }}
 
+        fn composite(&this,) -> () {{
+            this.downcast().composite_ok.set(true);
+            this.downcast().send_window_event(WindowEvent::Refresh);
+            this.downcast().composite_ok.set(false);
+        }}
+
         fn get_window_handle(&this,) -> cef_window_handle_t {{
             let t = this.downcast();
             let browser = t.browser.borrow();
@@ -189,6 +197,7 @@ impl ServoCefBrowserHost {
         ServoCefBrowserHost {
             browser: RefCell::new(None),
             client: client,
+            composite_ok: Cell::new(false),
         }
     }
 
diff --git a/ports/cef/window.rs b/ports/cef/window.rs
index 827e067c7fa..a73f2253fe8 100644
--- a/ports/cef/window.rs
+++ b/ports/cef/window.rs
@@ -296,12 +296,21 @@ impl WindowMethods for Window {
     fn prepare_for_composite(&self, width: usize, height: usize) -> bool {
         let browser = self.cef_browser.borrow();
         match *browser {
-            None => {}
+            None => {
+                panic!("No browser?!?");
+            }
             Some(ref browser) => {
-                browser.get_host().get_client().get_render_handler().paint(browser.clone(), width, height);
+                if browser.downcast().host.downcast().composite_ok.get() == true {
+                    true
+                } else {
+                    if check_ptr_exist!(browser.get_host().get_client(), get_render_handler) &&
+                       check_ptr_exist!(browser.get_host().get_client().get_render_handler(), on_paint) {
+                        browser.get_host().get_client().get_render_handler().paint(browser.clone(), width, height);
+                    }
+                    false
+                }
             }
         }
-        true
     }
 
     fn load_end(&self) {