Merge lp:~albaguirre/qtmir/ignore-first-frame into lp:qtmir

[Alberto Aguirre]

Ignore application first posted frame

Ignore the first posted frame as it will be blank. Since the surface
is alpha enabled it's alpha channel is initialized to 0 (completely
transparent). If the frame is posted it will show through a flash
of the surface beneath (usually dash).

Ignore application first posted frame

Ignore the first posted frame as it will be blank. Since the surface
is alpha enabled it's alpha channel is initialized to 0 (completely
transparent). If the frame is posted it will show through a flash
of the surface beneath (usually dash).

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:237
http://jenkins.qa.ubuntu.com/job/qtmir-ci/23/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/qtmir-utopic-amd64-ci/23
    SUCCESS: http://jenkins.qa.ubuntu.com/job/qtmir-utopic-armhf-ci/23

Click here to trigger a rebuild:
http://s-jenkins.ubuntu-ci:8080/job/qtmir-ci/23/rebuild

review: Approve (continuous-integration)

[Alberto Aguirre (albaguirre)]

The root cause is actually a bug in mir: https://bugs.launchpad.net/mir/+bug/1359406

Unmerged revisions

237. By Alberto Aguirre on 2014-08-20

Ignore application first posted frame

Ignore the first posted frame as it will be blank. Since the surface
is alpha enabled it's alpha channel is initialized to 0 (completely
transparent). If the frame is posted it will show through a flash
of the surface beneath (usually dash).

=== modified file 'src/modules/Unity/Application/mirsurfaceitem.cpp'
--- src/modules/Unity/Application/mirsurfaceitem.cpp	2014-08-12 18:23:06 +0000
+++ src/modules/Unity/Application/mirsurfaceitem.cpp	2014-08-20 19:05:50 +0000
@@ -216,7 +216,7 @@
 };
 
 MirSurfaceObserver::MirSurfaceObserver()
-    : m_listener(nullptr) {
+    : m_listener(nullptr), first_frame_posted(false) {
 }
 
 void MirSurfaceObserver::setListener(QObject *listener) {
@@ -225,6 +225,13 @@
 
 void MirSurfaceObserver::frame_posted(int frames_available) {
     Q_UNUSED(frames_available);
+
+    //Ignore the first frame, it's blank for some reason.
+    if (!first_frame_posted)
+    {
+        first_frame_posted = true;
+        return;
+    }
     QMetaObject::invokeMethod(m_listener, "surfaceDamaged");
 }
 
 
=== modified file 'src/modules/Unity/Application/mirsurfaceitem.h'
--- src/modules/Unity/Application/mirsurfaceitem.h	2014-07-23 11:57:49 +0000
+++ src/modules/Unity/Application/mirsurfaceitem.h	2014-08-20 19:05:50 +0000
@@ -62,6 +62,7 @@
     void orientation_set_to(MirOrientation) override {}
 private:
     QObject *m_listener;
+    bool first_frame_posted;
 };
 
 class MirSurfaceItem : public QQuickItem