summaryrefslogtreecommitdiffstats
path: root/src
diff options
context:
space:
mode:
authorMatt Hoosier <matt.hoosier@garmin.com>2013-05-16 11:01:23 -0500
committerThe Qt Project <gerrit-noreply@qt-project.org>2013-05-23 20:01:40 +0200
commit77a06e7e6c517003585ba53b9776e90c8d290e84 (patch)
treea685f2de81eae4a29578bdfa34c05c2a8163670d /src
parent47a7628023610904c6ac52e23fa289f75f349b4e (diff)
QNX: Support window translucency
A few tactical changes were necessary to do this: * The root window's buffer must be the full size of the window in order for transparency to work. We now transition this buffer to full-size upon first request of some QWindow to be translucent. At the same time the root window is transitioned to being full- screen, we also set its alpha blending mode to Source-Over in order to permit lower z-ordered apps to show through. * Set the root window's buffer position to (0, 0) to avoid a momentary flicker of unpainted pixels on the far right-hand border as a translucent window comes on-screen. * Use Source-Over alpha blending for normal child windows too. The QtGui core logic for setting the backing surface pixel format to something with an alpha channel if Qt::WA_TranslucentBackground is set on the toplevel QWidget already accomplished the remainder of the work. Change-Id: I1c2b31aa6323b4555fa194313f0f5e06ada494fc Reviewed-by: Kevin Krammer <kevin.krammer@kdab.com> Reviewed-by: Thomas McGuire <thomas.mcguire@kdab.com> Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com> Reviewed-by: Andreas Holzammer <andreas.holzammer@kdab.com>
Diffstat (limited to 'src')
-rw-r--r--src/plugins/platforms/qnx/qqnxrootwindow.cpp59
-rw-r--r--src/plugins/platforms/qnx/qqnxrootwindow.h4
-rw-r--r--src/plugins/platforms/qnx/qqnxwindow.cpp14
3 files changed, 72 insertions, 5 deletions
diff --git a/src/plugins/platforms/qnx/qqnxrootwindow.cpp b/src/plugins/platforms/qnx/qqnxrootwindow.cpp
index dddadb5ca8..5d58890c51 100644
--- a/src/plugins/platforms/qnx/qqnxrootwindow.cpp
+++ b/src/plugins/platforms/qnx/qqnxrootwindow.cpp
@@ -60,7 +60,8 @@ static const int MAGIC_ZORDER_FOR_NO_NAV = 10;
QQnxRootWindow::QQnxRootWindow(const QQnxScreen *screen)
: m_screen(screen),
m_window(0),
- m_windowGroupName()
+ m_windowGroupName(),
+ m_translucent(false)
{
qRootWindowDebug() << Q_FUNC_INFO;
// Create one top-level QNX window to act as a container for child windows
@@ -122,7 +123,10 @@ QQnxRootWindow::QQnxRootWindow(const QQnxScreen *screen)
if (result != 0)
qFatal("QQnxRootWindow: failed to set window size, errno=%d", errno);
- // Fill the window with solid black
+ // Fill the window with solid black. Note that the LSB of the pixel value
+ // 0x00000000 just happens to be 0x00, so if and when this root window's
+ // alpha blending mode is changed from None to Source-Over, it will then
+ // be interpreted as transparent.
errno = 0;
val[0] = 0;
result = screen_set_window_property_iv(m_window, SCREEN_PROPERTY_COLOR, val);
@@ -152,13 +156,62 @@ QQnxRootWindow::QQnxRootWindow(const QQnxScreen *screen)
qFatal("QQnxRootWindow: failed to set window source size, errno=%d", errno);
errno = 0;
- val[0] = 1;
+ val[0] = 0;
val[1] = 0;
result = screen_set_window_property_iv(m_window, SCREEN_PROPERTY_SOURCE_POSITION, val);
if (result != 0)
qFatal("QQnxRootWindow: failed to set window source position, errno=%d", errno);
createWindowGroup();
+
+ // Don't post yet. This will be lazily done from QQnxScreen upon first posting of
+ // a child window. Doing it now pre-emptively would create a flicker if one of
+ // the QWindow's about to be created sets its Qt::WA_TranslucentBackground flag
+ // and immediately triggers the buffer re-creation in makeTranslucent().
+}
+
+void QQnxRootWindow::makeTranslucent()
+{
+ if (m_translucent)
+ return;
+
+ int result;
+
+ errno = 0;
+ result = screen_destroy_window_buffers(m_window);
+ if (result != 0) {
+ qFatal("QQnxRootWindow: failed to destroy window buffer, errno=%d", errno);
+ }
+
+ QRect geometry = m_screen->geometry();
+ errno = 0;
+ int val[2];
+ val[0] = geometry.width();
+ val[1] = geometry.height();
+ result = screen_set_window_property_iv(m_window, SCREEN_PROPERTY_BUFFER_SIZE, val);
+ if (result != 0) {
+ qFatal("QQnxRootWindow: failed to set window buffer size, errno=%d", errno);
+ }
+
+ errno = 0;
+ result = screen_create_window_buffers(m_window, 1);
+ if (result != 0) {
+ qFatal("QQNX: failed to create window buffer, errno=%d", errno);
+ }
+
+ // Install an alpha channel on the root window.
+ //
+ // This is necessary in order to avoid interfering with any particular
+ // toplevel widget's QQnxWindow window instance from showing transparent
+ // if it desires.
+ errno = 0;
+ val[0] = SCREEN_TRANSPARENCY_SOURCE_OVER;
+ result = screen_set_window_property_iv(m_window, SCREEN_PROPERTY_TRANSPARENCY, val);
+ if (result != 0) {
+ qFatal("QQnxRootWindow: failed to set window transparency, errno=%d", errno);
+ }
+
+ m_translucent = true;
post();
}
diff --git a/src/plugins/platforms/qnx/qqnxrootwindow.h b/src/plugins/platforms/qnx/qqnxrootwindow.h
index aae1563c95..ea7c7faace 100644
--- a/src/plugins/platforms/qnx/qqnxrootwindow.h
+++ b/src/plugins/platforms/qnx/qqnxrootwindow.h
@@ -66,6 +66,8 @@ public:
void resize(const QSize &size);
+ void makeTranslucent();
+
QByteArray groupName() const { return m_windowGroupName; }
private:
@@ -74,6 +76,8 @@ private:
const QQnxScreen *m_screen;
screen_window_t m_window;
QByteArray m_windowGroupName;
+
+ bool m_translucent;
};
QT_END_NAMESPACE
diff --git a/src/plugins/platforms/qnx/qqnxwindow.cpp b/src/plugins/platforms/qnx/qqnxwindow.cpp
index f4cbb0e9db..7a1ffb98b8 100644
--- a/src/plugins/platforms/qnx/qqnxwindow.cpp
+++ b/src/plugins/platforms/qnx/qqnxwindow.cpp
@@ -117,9 +117,13 @@ QQnxWindow::QQnxWindow(QWindow *window, screen_context_t context)
if (result != 0)
qFatal("QQnxWindow: failed to set window alpha mode, errno=%d", errno);
- // Make the window opaque
+ // Blend the window with Source Over Porter-Duff behavior onto whatever's
+ // behind it.
+ //
+ // If the desired use-case is opaque, the Widget painting framework will
+ // already fill in the alpha channel with full opacity.
errno = 0;
- val = SCREEN_TRANSPARENCY_NONE;
+ val = SCREEN_TRANSPARENCY_SOURCE_OVER;
result = screen_set_window_property_iv(m_window, SCREEN_PROPERTY_TRANSPARENCY, &val);
if (result != 0)
qFatal("QQnxWindow: failed to set window transparency, errno=%d", errno);
@@ -370,6 +374,12 @@ void QQnxWindow::setBufferSize(const QSize &size)
qWarning() << "QQnxWindow: Buffer size was" << size;
qFatal("QQnxWindow: failed to create window buffers, errno=%d", errno);
+ // If the child window has been configured for transparency, lazily create
+ // a full-screen buffer to back the root window.
+ if (window()->requestedFormat().hasAlpha()) {
+ m_screen->rootWindow()->makeTranslucent();
+ }
+
// check if there are any buffers available
int bufferCount = 0;
result = screen_get_window_property_iv(m_window, SCREEN_PROPERTY_RENDER_BUFFER_COUNT, &bufferCount);