Commit Graph

3335 Commits

Author SHA1 Message Date
Andrew Knight
eea02ff10d WinRT: Support High-DPI
Previously, the backing store and default framebuffer were created with
the logical screen resolution (in device-independent pixels), not the
the physical screen resolution. This lead to blurry text on high-DPI
devices. This change fixes this by creating those at full size, and
setting the device pixel ratio appropriately. Windows are still reported
in device-independent pixels, but text and images are now rendered
sharply for Qt Quick applications.

As QPainter does not support non-integer scaling, the backing store is
still drawn in DIPs and scaled by OpenGL.

Task-number: QTBUG-38464
Change-Id: I7377d4c734126825d670b8ebb65fd0dd1ef705f2
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>
2014-05-22 07:59:49 +02:00
Andrew Knight
4c9eb38390 Support Windows Phone 8.1 in WinRT QPA
- Unsupported code paths for WP8.0 are avoided, and new APIs are used
  where appropriate (virtual keyboard)
- DirectWrite fonts are loaded on WP8.1
- Platform dialogs are used on WP8.1

Change-Id: I721006ac943ad4e248f0f1590ce247a03e40fbc0
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>
2014-05-22 07:59:49 +02:00
Louai Al-Khanji
26a2fb7448 Direct2D QPA: Move QVectorPath conversion function into private class
The function already needs information from the engine for conversion,
moving it into the private class makes it possible to get this info
directly in the method and makes calling the method nicer.

Change-Id: I47fa9a4531d0d0605aa587fba90fbfdf036f0998
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-22 06:07:04 +02:00
Louai Al-Khanji
bcab05cb4f Direct2D QPA: Get rid of QPainterPath conversion function
This function was used only in one place and duplicated a lot of logic
with the very similar QVectorPath conversion function. Just use
QVectorPath everywhere instead.

Change-Id: I3a4821f0452634c309ca0730047ea6ef7a7591ca
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-22 06:06:56 +02:00
Louai Al-Khanji
8d7e23ea0b Direct2D QPA: Cache QVectorPaths if drawn more than once
Hooking into the caching mechanism gets us a measurable performance boost
for paths that are drawn repeatedly, around 10% on my machine when drawing
aliased arcs.

Change-Id: I32f4ed7daa8a51b5c5a9c6d5414ab5d4ef759f70
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-22 06:06:51 +02:00
Jake Petroules
5d2939344e Trigger repaint of window when toggling unified toolbar on or off.
Change-Id: I5204e5c65ae3cf84459cc62f587ecccd855e02f8
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>
2014-05-22 02:52:54 +02:00
Christoph Schleifenbaum
ff31090d07 Cocoa: Do not process ampersands in menus twice.
When syncing between QAction and native NSMenuItems, the ampersands
(mnemonics) were removed twice. This lead to double ampersands being
removed instead of replace with single ones.

Task-number: QTBUG-37933
Change-Id: If1d9cd247b467472647b22b38460b44b03f13d82
Reviewed-by: Liang Qi <liang.qi@digia.com>
2014-05-21 13:59:18 +02:00
Christian Strømme
849f8f58ce Android: Fix crash caused by unintentionally modification of env data.
The data given to putenv(3) becomes a part of the environment, as
described in SUSv2, so If the data is unintentionally modified or
deleted the consequence can be fatal.
In previous versions of Android, the putenv(3) implementation made a
copy of the data, so this bug has gone unnoticed.

Task-number: QTBUG-39042
Change-Id: I20559c848fded10eeae54c4700ba0f4669fe49fc
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
2014-05-21 01:34:38 +02:00
Richard Moe Gustavsen
bf50bf737b iOS: don't report negative selection ranges for backspace
Qt sometimes report that the selection anchor is placed before
the cursor when querying it for current selection. We need to
accomodate for this when reporting current selection back to
iOS, since it expects the range to always be positive.

When pressing backspace, iOS will select the letter that should be
deleted, and then call "deleteBackwards". If holding down backspace
for a while, it will start selecting whole words instead.
Since we reported negative ranges during this process, it caused
artifacts and stray letters to be drawn.

Task-number: QTBUG-39073
Change-Id: Ida9518307adce915adf49160b541a2f88637a0da
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>
2014-05-21 01:34:38 +02:00
Friedemann Kleint
043529c9dc Windows QPA: Remove dependency on swprintf_s() pulled in via _com_error::ErrorMessage().
Task-number: QTBUG-35617
Change-Id: I0ad926ac564612ebd0eb38f16b3e69cbcd48e62f
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
2014-05-19 15:52:58 +02:00
Frederik Gladhorn
6ef8eee8d4 Fix potential null pointer access
Change-Id: I7516ce88b38609ab9851419566141ba93a59aed3
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-19 15:52:58 +02:00
Louai Al-Khanji
828656241b Direct2D QPA: Use correct buffer size constant
Change-Id: I2d8ec5faed959d6d642242b3e26ee0f185ee3d53
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-19 15:52:58 +02:00
Louai Al-Khanji
58caefa13e Direct2D QPA: Stroke using direct2d primitives
Use native direct2d stroking instead of falling back to
QPaintEngineEx::stroke which in turn calls the pure virtual
QPaintEngineEx::fill which is reimplemented in QWindowsDirect2DPaintEngine.

In some cases like arc stroking this is significantly faster (up to 3x in
my measurements) and results in better visual quality.

Change-Id: I1c86ff772ba591432ff6550c7c59704ace4f0e0f
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-19 15:52:58 +02:00
Louai Al-Khanji
35766fbe47 Direct2D QPA: Fix version check
It turns out that the version we were testing against was more recent than
basic Windows 7 SP1 + Platform Update. The direct2d version that
combination produces without any other updates is 6.2.9200.16492, and it
is sufficient for us.

Change-Id: Ib9840647371e2bb5c71bf74486348444ed4b4c19
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-19 15:52:58 +02:00
Dyami Caliri
71006cf04c CoreWLan: wait for scan thread to finish
If the scan thread is running when QCoreWlanEngine is destroyed
it will access stale data and cause a crash.

Task-number: QTBUG-36000
Change-Id: I8cc9e39a3f7d4736da39e8b31f6963db35318f19
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>
Reviewed-by: Peter Hartmann <phartmann@blackberry.com>
2014-05-18 18:29:35 +02:00
Frederik Gladhorn
1248eddd14 Accessibility Android: Fix states
Using the bit flags as parameters to the JNI functions would fail since
they'd always be cast to false instead of the c-style casts.

This fixes checkboxes reporting themselves as checkable and their check
state.

Task-number: QTBUG-38831
Change-Id: I30ab63ceabbec4cc2fbda9475e05523d915087fe
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
2014-05-16 14:28:30 +02:00
Frederik Gladhorn
94f9c9678a Merge "Merge remote-tracking branch 'origin/release' into stable" into refs/staging/stable 2014-05-16 14:14:25 +02:00
Richard Moe Gustavsen
986309cbf0 cocoa: remove rtf converter from cocoa
There is now a modified rtf converter in qmacmime
that can also write rtf back to the pasteboard, and
that works on both OS X and iOS.
So we can therefore remove the one from the cocoa port.

Change-Id: Ieed04502752290d2f139f98cec69477ff1edbe4e
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>
2014-05-16 14:10:36 +02:00
Richard Moe Gustavsen
6388163df8 qmacmime: rename and move QMacPasteboardMimePlainText to the cocoa plugin
com.apple.traditional-mac-plain-text is not in use on iOS
according to Apples UTType reference. So we enable it only
for OS X by moving it into the cocoa port.

The order in which we instanciate convertors matters when
the application is reading data from the pasteboard.
But since QMacPasteboardMimePlainText should come before the
other "text/plain" convertors on OS X, moving it to the cocoa
port is safe as those convertors are instanciated after
those in qmacmime.

Change-Id: I76b9b14e5ce78f34e0f1ecbfee71e48a27a4687b
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>
2014-05-16 14:10:32 +02:00
Eskil Abrahamsen Blomfeldt
08117eee00 Android: Support QFont::Courier style hint
Android doesn't have a serif monospaced font, so for the courier
style hint we at least need to fall back to something monospaced,
which is "Droid Sans Mono" on Android.

[ChangeLog][Android][Text] Fall back to Droid Sans Mono for
QFont::Courier style hint.

Task-number: QTBUG-37844
Change-Id: Ib42caf53a8fb7b9958e10a8f123cac928eee7069
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>
2014-05-14 20:10:03 +02:00
Louai Al-Khanji
bf284c2bbd Direct2D QPA: Fix check for cosmetic pen
When checking whether a QPen should be treated as cosmetic we need to
take into account the render hints set on the painter as well.

Change-Id: I8200611af08000d2d1626d8ef97eb3f6dac4951c
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
2014-05-14 13:17:17 +02:00
Frederik Gladhorn
cb3348dec9 Merge remote-tracking branch 'origin/release' into stable
Change-Id: If1abbe7810ea43ae750db91066f9f579c79b2289
2014-05-14 12:37:34 +02:00
Eskil Abrahamsen Blomfeldt
d16508a285 Fix crash when loading invalid font data in QRawFont
When passing invalid data to QRawFont, we need to fail gracefully
and mark the font as invalid, instead of crashing. This crashed
because of different missing sanity checks in the Windows
and FontConfig font databases.

[ChangeLog][Text] Fixed crash when trying to load a font from
invalid data.

Task-number: QTBUG-37190
Change-Id: I62c81217ec7d873350b575c9d4ae8e6f0a939540
Reviewed-by: Michael Bruning <michael.bruning@digia.com>
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
2014-05-14 09:13:38 +02:00
Frederik Gladhorn
06e27c2a52 Accessibility Android: Fix crash for invalid interfaces
When asked for an accessibility interface with invalid ID we still
return an AccessibilityNodeInfo. But instead of setting that interfaces'
ID to the invalid ID, rather return one with no ID set so it will simply
fall back to the view.

Task-number: QTBUG-38829
Change-Id: If66f5b1b42ba46949d94a547050c7a2cfc7ee9b7
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
2014-05-13 22:10:21 +02:00
Frederik Gladhorn
12ba0d2cb3 Merge "Merge remote-tracking branch 'origin/release' into stable" into refs/staging/stable 2014-05-13 14:16:46 +02:00
Andy Shaw
79d35b331a Fix horizontal scrolling on Windows when ALT + mouse wheel is used
Task-number: QTBUG-30833
Change-Id: I366d2979060ba67f745f7c783dee8d7669ebdf57
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-13 14:12:02 +02:00
Allan Sandfeld Jensen
a8877f529d Scrolling devices should not override touch or tablet devices
XISelectEvents override any earlier set event mask for the same device
ids. This may cause touch devices to stop reporting touch events if they
export scroll buttons or axis.

The patch checks for each scrolling device if they are also a touch
devices and includes the necessary bitmask if they are, and skips
any devices also recognized as tablet devices as they already capture
all relevant events.

In addition tablet event handling will no longer block handling of wheel
button events for scroll devices with the same device id.

Task-number: QTBUG-38935
Change-Id: Ifd4657beb0a0cebffe89d3470ef2bd605eb3552e
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
2014-05-13 12:47:16 +02:00
Allan Sandfeld Jensen
7cc175c9d6 Assume unlabelled mouse buttons are default buttons
This patch fixes legacy wheel scrolling for XInput2 drivers that fail to
label mouse buttons correctly.

Task-number: QTBUG-38937
Change-Id: I659890517e749dc0039489e0b7a8c38be1065d33
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
2014-05-13 12:47:12 +02:00
Bernd Weimer
8094bb537a QNX: Silence startup warnings
Missing PPS objects for navigator, virtual keyboard and buttons can be
expected on QNX and should not lead to warnings.
Virtual keyboard info message does not contain locale object any more.

Change-Id: I447d439ffbf4ea6e03f6a8bca4422a9a121d85f4
Reviewed-by: Frank Osterfeld <frank.osterfeld@kdab.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
2014-05-13 08:42:46 +02:00
Bernd Weimer
da6dc40f75 QNX: Don't build QNX-only parts on BlackBerry
Only really required source files will be included when building for
BlackBerry.

Change-Id: Ic66b09221c48672358bba7601bc18663ad7fa07a
Reviewed-by: Wolfgang Bremer <wbremer@blackberry.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
2014-05-12 18:15:20 +02:00
Andreas Holzammer
5883b6a22c [QNX]Clear transparent regions
If a region gets painted the buffer beneath needs
to be cleared, as it could be that there are
leftovers from the last blit.

Change-Id: I51f19aa010015059e9a6d9d5e5e4f25fb9532d4e
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>
2014-05-12 17:30:57 +02:00
Frederik Gladhorn
73bc91c9df Merge remote-tracking branch 'origin/release' into stable
Change-Id: I9300572e2b74f0564b2589cbd0fbdf24850f68df
2014-05-12 14:01:46 +02:00
Louai Al-Khanji
6c42ddf31f Direct2D QPA: Choose linear interpolation for smooth pixmap transform
Let's do the same thing the raster engine does. Much faster too.

Change-Id: I88ea9d2c2ac78feee1193b75a9e96c62a7bd5979
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-12 13:44:42 +02:00
Louai Al-Khanji
17dda3917d Direct2D QPA: Never queue more than one frame
Microsoft recommends setting the maximum frame latency to 1:

http://blogs.windows.com/windows/b/appbuilder/archive/2013/12/18/optimizing-directx-apps-for-low-latency-input-and-longer-battery-life.aspx
http://msdn.microsoft.com/en-us/library/windows/desktop/hh780339(v=vs.85).aspx

Apparently it slightly reduces power consumption and it also slightly
increases performance. So let's set it.

Change-Id: I8a540f1e54e83d6dc13f25564e10b751e202ce66
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-12 13:44:38 +02:00
Louai Al-Khanji
f85ab84414 Direct2D QPA: Bump copyright year to match reality
Change-Id: I443b74e3d464285febc28345f35d1445e8102015
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-09 12:17:44 +02:00
Rolf Eike Beer
6f6cfda8c4 kms plugin: use first returned mode if no preferred one is present
The list of returned modes is scanned for the first one marked as
preferred, and that is used. If no preferred mode was found then the
builtin default mode of 1024x768 is used. Use that builtin mode only if
no modes were returned at all, pick the first one if any were returned.

Change-Id: Ib355cc92219ced093c605f49dae4e34ff244b639
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
2014-05-08 16:33:31 +02:00
Rolf Eike Beer
9c4996b709 kms plugin: do not needlessly query drm information twice
QKmsDevice already requested the drmModeRes and drmModeConnector
information. Simply pass them to the QKmsScreen constructor instead of
requesting and freeing them there again.

Change-Id: I4897d76d7b13d83297c928b6e10e17ccdfdbd242
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
2014-05-08 16:33:21 +02:00
Frederik Gladhorn
730697d1b9 Accessibility Android: Make debug tags consistent
Change-Id: I712e64002234d546365b44ca15ae93e8decac882
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
2014-05-08 13:50:22 +02:00
Paul Olav Tvete
eed30131e1 Android: text cursor position fixes
The Android input method protocol specifies that finishComposingText()
should not move the cursor. Since Qt likes to move the cursor to the
end of the newly committed text, we have to explicitly move the cursor
to where the preedit cursor used to be. Fortunately we already keep
track of that.

Also implement support for the newCursorPosition argument to commitText()
since the function needed to be rewritten anyway. (It was calling
finishComposingText().)

Task-number: QTBUG-38794
Change-Id: Iff2c43bdbd3dda812ccdc71da63f3fa730474eef
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
2014-05-08 13:50:22 +02:00
Tor Arne Vestbø
36caeadb4d iOS: Gracefully handle cancelling of subset of active touches
When applying the five-finger pinch gesture, we get a touchesCancelled
callback with all five touch points, but the pinch gesture ends when
the second to last finger is released from the screen. The last finger
will not emit any more touch events, _but_, will contribute to starting
another pinch gesture. That second pinch gesture will _not_ trigger a
touchesCancelled event when starting, but as each finger is released,
and we may get touchesMoved events for the remaining fingers.

The event property 'allTouches' contains one less touch point than it
should, so this behavior is likely a bug in the iOS system gesture
recognizer, but have to take it into account when maintaining the Qt
touch state.

We do this by assuming that there are no cases where a sub-set of the
active touch events are intentionally cancelled, and always clear the
list of active touches.

Task-number: QTBUG-37304
Change-Id: Icee79978508ecbc6854c0fb55d2da48b99d92f96
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@digia.com>
2014-05-08 13:50:22 +02:00
Liang Qi
d7e0c926b5 Android: remove the duplicate registration for qt accessibility
Change-Id: I3241138e39b93657aee0564442f22ad0c40328d4
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>
Reviewed-by: BogDan Vatra <bogdan@kde.org>
2014-05-08 13:50:22 +02:00
Louai Al-Khanji
70accc289a Direct2D QPA: Check Direct2D version
Since we require a relatively recent system, check the version of the
direct2d dll on disk and report an error to the user if it is too old.
Previously only a cryptic runtime error resulted from a direct2d version
that was too old.

Change-Id: I6c3955e1a98326fca6bcdc871b0a25291391ba88
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-07 18:01:41 +02:00
Louai Al-Khanji
bfa0d149f6 Direct2D QPA: Speed up text rendering
After analysing text drawing performance two things seem to take up most
of the time. The first is font lookup, the second is QVector
initialization.

To address the first point a per paint engine instance font cache is
introduced. At the moment no mechanism exists to clear this cache and
it is unbounded.

To address the second point, we simply switch to using QVarLengthArray
instead of QVector.

In an artificial benchmark that draws text in a tight loop, the first
change raised fps from ~70 to ~100. The second change further raised this
number to ~115 fps.

Change-Id: Iafa25c3e35bc42bd7c1582b0636e721c5193b494
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
2014-05-07 18:01:37 +02:00
Frederik Gladhorn
fdcf66f10f Accessibility Android: Do not always append role
Task-number: QTBUG-36584
Change-Id: Id14962a9eb7a6c3ea78cefcfcc053fac886ba8f7
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
2014-05-07 13:07:36 +02:00
Friedemann Kleint
319e90dcdd Windows: Use Format_ARGB32_Premultiplied for backing store with alpha.
Following the logic in Qt 4's QRasterWindowSurface::setGeometry().

Task-number: QTBUG-30302
Change-Id: Ica571cfd5098e3d9faedefaff0880acfb2209958
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
2014-05-06 16:35:56 +02:00
Jørgen Lind
2bc619c30e Add virtual function to QFontEngine report if outlines are reliable
GetGlyphOutline fails for ttf fonts with embedded bitmaps. This results in
distancefield rendering not rendering glyphs (for the failed paths). We
need to fall back to texture rendering if this is the case.

Change-Id: Ibdf7dc5c1d34f513c436f88fabbdcc4089bb6fef
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
2014-05-06 16:35:56 +02:00
Frederik Gladhorn
3b8d140558 Accessibility: Do not report popup for QLineEdit
Nothing else seems to report this state and on windows
for example it results in NVDA reading subMenu which makes
little sense.
Task-number: QTBUG-38500
Change-Id: I64820d9f2ea9174034f01da42cb2266a19c19465
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
2014-05-06 16:35:56 +02:00
Louai Al-Khanji
1fdd765ae8 Direct2D QPA: Fix DXGI Factory discovery magic
On some Intel configurations the current DXGI discovery breaks. Fix this
by adhering to Microsoft's guidelines for discovery of the DXGI factory:

http://msdn.microsoft.com/en-us/library/windows/desktop/hh780339(v=vs.85).aspx

Not querying the adapter directly as in the code snippet on the site above
seems to have been a typo originally.

Change-Id: Ibd7546462cdab7e5ad03db9abc16fe1615b631f4
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
2014-05-05 14:13:50 +02:00
Andrew Knight
ad8efdbc0c WinRT: set orientation update mask to native orientation by default
This aligns with the other mobile platforms.

Task-number: QTBUG-38691
Change-Id: I7b9b70a1182c0e53f997cae111ec46b5161b0b48
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>
2014-05-05 14:13:50 +02:00
Louai Al-Khanji
ac448335f1 Direct2D QPA: Draw directly to swap chain
Remove the intermediate pixmap in the backing store and draw directly to
the window swap chain. This is faster and reduces memory pressure on the
graphics card.

In case of native child widgets we need to read back the back buffer,
which incurs an extra copy in this case.

In an artificial benchmark drawing animated full screen
gradients as fast as possible this patch increases performance by 42% on
my current machine from 480fps to around 680fps, i.e. the time for
actually getting the pixels to the screen is now lower.

Change-Id: Ifbeda0e199afec03cecfe76337679a9e9d082bdd
Reviewed-by: Risto Avila <risto.avila@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
2014-05-05 14:13:50 +02:00