Add mouse event synthesizing to the touch extension protocol.

The compositor can now be configured to tell the clients to generate
mouse events when receiving touch events. In touchscreen-only systems
this can be used to reduce the number of Wayland events.

Change-Id: I231a15cd4ed463ee81c510c082a270efa255a1f3
Reviewed-by: Jørgen Lind <jorgen.lind@nokia.com>

3 files changed, 15 insertions, 1 deletions

diff --git a/examples/qwindow-compositor/qopenglwindow.cpp b/examples/qwindow-compositor/qopenglwindow.cpp
index d70c4a965..473e4c151 100644
--- a/examples/qwindow-compositor/qopenglwindow.cpp
+++ b/examples/qwindow-compositor/qopenglwindow.cpp
@@ -39,6 +39,7 @@
 ****************************************************************************/
 
 #include "qopenglwindow.h"
+#include <QTouchEvent>
 
 QOpenGLWindow::QOpenGLWindow(const QSurfaceFormat &format, const QRect &geometry)
     : m_format(format)
@@ -51,3 +52,10 @@ QOpenGLWindow::QOpenGLWindow(const QSurfaceFormat &format, const QRect &geometry
     m_context->setFormat(format);
     m_context->create();
 }
+
+void QOpenGLWindow::touchEvent(QTouchEvent *event)
+{
+    // Do not want any automatically synthesized mouse events
+    // so make sure the touch is always accepted.
+    event->accept();
+}
diff --git a/examples/qwindow-compositor/qopenglwindow.h b/examples/qwindow-compositor/qopenglwindow.h
index 0d1cfbf7a..2ba883cf0 100644
--- a/examples/qwindow-compositor/qopenglwindow.h
+++ b/examples/qwindow-compositor/qopenglwindow.h
@@ -53,7 +53,8 @@ public:
     QOpenGLContext* context() { return m_context; }
     bool makeCurrent() { return m_context->makeCurrent(this); }
     void swapBuffers() { m_context->swapBuffers(this); }
-
+protected:
+    void touchEvent(QTouchEvent *event);
 private:
     QOpenGLContext *m_context;
     QSurfaceFormat m_format;
diff --git a/examples/qwindow-compositor/qwindowcompositor.cpp b/examples/qwindow-compositor/qwindowcompositor.cpp
index 90192f98d..a7132101e 100644
--- a/examples/qwindow-compositor/qwindowcompositor.cpp
+++ b/examples/qwindow-compositor/qwindowcompositor.cpp
@@ -58,6 +58,11 @@ QWindowCompositor::QWindowCompositor(QOpenGLWindow *window)
     // using a custom protocol extension.
     // enableTouchExtension();
 
+    // Enable the following to have mouse events generated from touch
+    // on client side. This is not the same as synthesizing mouse events
+    // in the compositor because it avoids sending data through the wire.
+    // configureTouchExtension(WaylandCompositor::TouchExtMouseFromTouch);
+
     enableSubSurfaceExtension();
     m_window->makeCurrent();