qtwayland_%.bbappend: Do not enable by default resize after swap envsandbox/mvlad/fix-invalid-resize

variable

In our use-cases applications do not specify a size for the windows,
leaving qtwayland itself to create an initial size for the surface (a
500 by 500 size). The compositor will send a configure event back to
the application with the available/actual geometry area, resulting in
resize performed by the application.

This, in tandem with the fact that we tweaked qtwayland to perform the
resize (due to SPEC-3334) after a buffer swap results in a short flicker
-- the application does an initial commit with that initial size but
with no background or any information attached to it. The environmental
variable tunes the repainting mechanism in qtwayland affecting the way
the resize is performed and was added because for multiple or split
surfaces destroying one of them will not cause a scale back to the
original area.

We therefore disable by default that environment variable and leave it
to the applications to enable it at start-up, if they still want to use
split type of surfaces. Added a rather big comment about why that might
necessary giving some clues and some mention that qtwayland doesn't make
a distinction of the value of the environmental variable itself.

Bug-AGL: SPEC-3522

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
Change-Id: I63a5a34a625169e0af3e92c16f2aba7b2e750ec2

1 files changed, 8 insertions, 1 deletions

diff --git a/meta-agl-profile-graphical-qt5/recipes-qt/qt5/qtwayland_%.bbappend b/meta-agl-profile-graphical-qt5/recipes-qt/qt5/qtwayland_%.bbappend
index 85ebc29..cdbb0c3 100644
--- a/meta-agl-profile-graphical-qt5/recipes-qt/qt5/qtwayland_%.bbappend
+++ b/meta-agl-profile-graphical-qt5/recipes-qt/qt5/qtwayland_%.bbappend
@@ -31,5 +31,12 @@ QT_SHELL_FILE = "${AFM_CONF_DIR}/qt-shell"
 do_install_append_class-target() {
 	mkdir -p ${AFM_CONF_DIR}
 	echo "QT_WAYLAND_SHELL_INTEGRATION=${AGL_DEFAULT_WM_SHELL}" > ${QT_SHELL_FILE}
-	echo "QT_WAYLAND_RESIZE_AFTER_SWAP=1" >> ${QT_SHELL_FILE}
+	echo -ne "# The following might be necessary to be enabled when multiple/split surfaces\n"\
+		"# are created. Without this enabled, QtWayland will sometimes maintain the same/old\n"\
+		"# size even if the split surface is destroyed. We keep it disabled by default as it\n"\
+		"# causes an additional repaint of the surface until the compositor sends a configure\n"\
+		"# event to scale the window to the actual area. Typical windows will default to a initial\n"\
+		"# size when starting-up without an explicit size specified. Note that QtWayland will only test\n"\
+	        "# the presence of the environment variable so it will be enabled even if set to 0\n" >> ${QT_SHELL_FILE}
+	echo "#QT_WAYLAND_RESIZE_AFTER_SWAP=1" >> ${QT_SHELL_FILE}
 }