diff options
Diffstat (limited to 'src/gui/kernel/qplatformgraphicsbuffer.cpp')
| -rw-r--r-- | src/gui/kernel/qplatformgraphicsbuffer.cpp | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/src/gui/kernel/qplatformgraphicsbuffer.cpp b/src/gui/kernel/qplatformgraphicsbuffer.cpp new file mode 100644 index 0000000000..f032601b29 --- /dev/null +++ b/src/gui/kernel/qplatformgraphicsbuffer.cpp @@ -0,0 +1,277 @@ +/**************************************************************************** +** +** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies). +** Contact: http://www.qt-project.org/legal +** +** This file is part of the QtGui module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and Digia. For licensing terms and +** conditions see http://qt.digia.com/licensing. For further information +** use the contact form at http://qt.digia.com/contact-us. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Digia gives you certain additional +** rights. These rights are described in the Digia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qplatformgraphicsbuffer.h" +#include <QtGui/QOpenGLContext> +#include <QtGui/QOpenGLFunctions> +#include <QtGui/qopengl.h> +#include <QtCore/QDebug> + +QT_BEGIN_NAMESPACE +/*! + \class QPlatformGraphicsBuffer + \inmodule QtGui + \since 5.5 + \brief The QPlatformGraphicsBuffer is a windowsystem abstraction for native graphics buffers + + Different platforms have different ways of representing graphics buffers. On + some platforms, it is possible to create one graphics buffer that you can bind + to a texture and also get main memory access to the image bits. On the + other hand, on some platforms all graphics buffer abstraction is completely + hidden. + + QPlatformGraphicsBuffer is an abstraction of a single Graphics Buffer. + + There is no public constructor nor any public factory function. + + QPlatformGraphicsBuffer is intended to be created by using platform specific + APIs available from QtPlatformHeaders, or there might be accessor functions + similar to the accessor function that QPlatformBackingstore has. +*/ + +/*! + \enum QPlatformGraphicsBuffer::AccessType + + This enum describes the access that is desired or granted for the graphics + buffer. + + \value None + \value SWReadAccess + \value SWWriteAccess + \value TextureAccess + \value HWCompositor +*/ + +/*! + \enum QPlatformGraphicsBuffer::Origin + + This enum describes the origin of the content of the buffer. + + \value OriginTopLeft + \value OriginBottomLeft +*/ + +/*! + Protected constructor to initialize the private members. + + \a size is the size of the buffer. + \a format is the format of the buffer. + + \sa size() format() +*/ +QPlatformGraphicsBuffer::QPlatformGraphicsBuffer(const QSize &size, const QPixelFormat &format) + : m_size(size) + , m_format(format) +{ +} + + +/*! + Virtual destructor. +*/ +QPlatformGraphicsBuffer::~QPlatformGraphicsBuffer() +{ +} + +/*! + Binds the content of this graphics buffer into the currently bound texture. + + This function should fail for buffers not capable of locking to TextureAccess. + + \a rect is the subrect which is desired to be bounded to the texture. This + argument has a no less than semantic, meaning more (if not all) of the buffer + can be bounded to the texture. An empty QRect is interpreted as entire buffer + should be bound. + + This function only supports binding buffers to the GL_TEXTURE_2D texture + target. + + Returns true on success, otherwise false. +*/ +bool QPlatformGraphicsBuffer::bindToTexture(const QRect &rect) const +{ + Q_UNUSED(rect); + return false; +} + +/*! + \fn QPlatformGraphicsBuffer::AccessTypes QPlatformGraphicsBuffer::isLocked() const + Function to check if the buffer is locked. + + \sa lock() +*/ + +/*! + Before the data can be retrieved or before a buffer can be bound to a + texture it needs to be locked. This is a separate function call since this + operation might be time consuming, and it would not be satisfactory to do + it per function call. + + \a access is the access type wanted. + + \a rect is the subrect which is desired to be locked. This + argument has a no less than semantic, meaning more (if not all) of the buffer + can be locked. An empty QRect is interpreted as entire buffer should be locked. + + Return true on successfully locking all AccessTypes specified \a access + otherwise returns false and no locks have been granted. +*/ +bool QPlatformGraphicsBuffer::lock(AccessTypes access, const QRect &rect) +{ + bool locked = doLock(access, rect); + if (locked) + m_lock_access |= access; + + return locked; +} + +/*! + Unlocks the current buffer lock. + + This function calls doUnlock, and then emits the unlocked signal with the + AccessTypes from before doUnlock was called. +*/ +void QPlatformGraphicsBuffer::unlock() +{ + if (m_lock_access == None) + return; + AccessTypes previous = m_lock_access; + doUnlock(); + m_lock_access = None; + emit unlocked(previous); +} + + +/*! + \fn QPlatformGraphicsBuffer::doLock(AccessTypes access, const QRect &rect = QRect()) + + This function should be reimplemented by subclasses. If one of the \a + access types specified can not be locked, then all should fail and this + function should return false. + + \a rect is the subrect which is desired to be locked. This + argument has a no less than semantic, meaning more (if not all) of the + buffer can be locked. An empty QRect should be interpreted as the entire buffer + should be locked. + + It is safe to call isLocked() to verify the current lock state. +*/ + +/*! + \fn QPlatformGraphicsBuffer::doUnlock() + + This function should remove all locks set on the buffer. + + It is safe to call isLocked() to verify the current lock state. +*/ + +/*! + \fn QPlatformGraphicsBuffer::unlocked(AccessTypes previousAccessTypes) + + Signal that is emitted after unlocked has been called. + + \a previousAccessTypes is the access types locked before unlock was called. +*/ + +/*! + Accessor for the bytes of the buffer. This function needs to be called on a + buffer with SWReadAccess access lock. Behavior is undefined for modifying + the memory returned when not having a SWWriteAccess. +*/ +const uchar *QPlatformGraphicsBuffer::data() const +{ return Q_NULLPTR; } + +/*! + Accessor for the bytes of the buffer. This function needs to be called on a + buffer with SWReadAccess access lock. Behavior is undefined for modifying + the memory returned when not having a SWWriteAccess. +*/ +uchar *QPlatformGraphicsBuffer::data() +{ + return Q_NULLPTR; +} + +/*! + Accessor for the length of the data buffer. This function is a convenience + function multiplying height of buffer with bytesPerLine(). + + \sa data() bytesPerLine() size() +*/ +int QPlatformGraphicsBuffer::byteCount() const +{ + Q_ASSERT(isLocked() & SWReadAccess); + return size().height() * bytesPerLine(); +} + +/*! + Accessor for bytes per line in the graphics buffer. +*/ +int QPlatformGraphicsBuffer::bytesPerLine() const +{ + return 0; +} + + +/*! + In origin of the content of the graphics buffer. + + Default implementation is OriginTopLeft, as this is the coordinate + system default for Qt. However, for most regular OpenGL textures + this will be OriginBottomLeft. +*/ +QPlatformGraphicsBuffer::Origin QPlatformGraphicsBuffer::origin() const +{ + return OriginTopLeft; +} + +/*! + \fn QPlatformGraphicsBuffer::size() const + + Accessor for content size. +*/ + +/*! + \fn QPlatformGraphicsBuffer::format() const + + Accessor for the pixel format of the buffer. +*/ + +QT_END_NAMESPACE |