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|
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtOpenGL module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** 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, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, 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.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://www.qtsoftware.com/contact.
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qglframebufferobject.h"
#include <qdebug.h>
#include <private/qgl_p.h>
#if !defined(QT_OPENGL_ES_1) && !defined(QT_OPENGL_ES_1_CL)
#include <private/qpaintengineex_opengl2_p.h>
#endif
#ifndef QT_OPENGL_ES_2
#include <private/qpaintengine_opengl_p.h>
#endif
#include <qglframebufferobject.h>
#include <qlibrary.h>
#include <qimage.h>
#ifdef QT_OPENGL_ES_1_CL
#include "qgl_cl_p.h"
#endif
QT_BEGIN_NAMESPACE
extern QImage qt_gl_read_framebuffer(const QSize&, bool, bool);
#define QGL_FUNC_CONTEXT QGLContext *ctx = d_ptr->ctx;
#define QT_CHECK_GLERROR() \
{ \
GLenum err = glGetError(); \
if (err != GL_NO_ERROR) { \
qDebug("[%s line %d] GL Error: %d", \
__FILE__, __LINE__, (int)err); \
} \
}
class QGLFramebufferObjectFormatPrivate
{
public:
int samples;
QGLFramebufferObject::Attachment attachment;
GLenum target;
GLenum internal_format;
};
/*!
\class QGLFramebufferObjectFormat
\brief The QGLFramebufferObjectFormat class specifies the format of an OpenGL
framebuffer object.
\since 4.6
\ingroup multimedia
A framebuffer object has several characteristics:
\list
\i \link setSamples() Number of samples per pixels.\endlink
\i \link setAttachment() Depth and/or stencil attachments.\endlink
\i \link setTextureTarget() Texture target.\endlink
\i \link setInternalFormat() Internal format.\endlink
\endlist
Note that the desired attachments or number of samples per pixels might not
be supported by the hardware driver. Call QGLFramebufferObject::format()
after creating a QGLFramebufferObject to find the exact format that was
used to create the frame buffer object.
\sa QGLFramebufferObject
*/
/*!
\since 4.6
Creates a QGLFramebufferObjectFormat object with properties specifying
the format of an OpenGL framebuffer object.
A multisample framebuffer object is specified by setting \a samples
to a value different from zero. If the desired amount of samples per pixel is
not supported by the hardware then the maximum number of samples per pixel
will be used. Note that multisample framebuffer objects can not be bound as
textures. Also, the \c{GL_EXT_framebuffer_multisample} extension is required
to create a framebuffer with more than one sample per pixel.
For multisample framebuffer objects a color render buffer is created,
otherwise a texture with the texture target \a target is created.
The color render buffer or texture will have the internal format
\a internalFormat, and will be bound to the \c GL_COLOR_ATTACHMENT0
attachment in the framebuffer object.
The \a attachment parameter describes the depth/stencil buffer
configuration.
\sa samples(), attachment(), target(), internalFormat()
*/
QGLFramebufferObjectFormat::QGLFramebufferObjectFormat(int samples,
QGLFramebufferObject::Attachment attachment,
GLenum target,
GLenum internalFormat)
{
d = new QGLFramebufferObjectFormatPrivate;
d->samples = samples;
d->attachment = attachment;
d->target = target;
d->internal_format = internalFormat;
}
/*!
\since 4.6
Constructs a copy of \a other.
*/
QGLFramebufferObjectFormat::QGLFramebufferObjectFormat(const QGLFramebufferObjectFormat &other)
{
d = new QGLFramebufferObjectFormatPrivate;
*d = *other.d;
}
/*!
\since 4.6
Assigns \a other to this object.
*/
QGLFramebufferObjectFormat &QGLFramebufferObjectFormat::operator=(const QGLFramebufferObjectFormat &other)
{
*d = *other.d;
return *this;
}
/*!
\since 4.6
Destroys the QGLFramebufferObjectFormat.
*/
QGLFramebufferObjectFormat::~QGLFramebufferObjectFormat()
{
delete d;
}
/*!
\since 4.6
Sets the number of samples per pixel for a multisample framebuffer object
to \a samples.
A sample count of 0 represents a regular non-multisample framebuffer object.
\sa samples()
*/
void QGLFramebufferObjectFormat::setSamples(int samples)
{
d->samples = samples;
}
/*!
\since 4.6
Returns the number of samples per pixel if a framebuffer object
is a multisample framebuffer object. Otherwise, returns 0.
\sa setSamples()
*/
int QGLFramebufferObjectFormat::samples() const
{
return d->samples;
}
/*!
\since 4.6
Sets the attachments a framebuffer object should have to \a attachment.
\sa attachment()
*/
void QGLFramebufferObjectFormat::setAttachment(QGLFramebufferObject::Attachment attachment)
{
d->attachment = attachment;
}
/*!
\since 4.6
Returns the status of the depth and stencil buffers attached to
a framebuffer object.
\sa setAttachment()
*/
QGLFramebufferObject::Attachment QGLFramebufferObjectFormat::attachment() const
{
return d->attachment;
}
/*!
\since 4.6
Sets the texture target of the texture attached to a framebuffer object to
\a target. Ignored for multisample framebuffer objects.
\sa textureTarget(), samples()
*/
void QGLFramebufferObjectFormat::setTextureTarget(GLenum target)
{
d->target = target;
}
/*!
\since 4.6
Returns the texture target of the texture attached to a framebuffer object.
Ignored for multisample framebuffer objects.
\sa setTextureTarget(), samples()
*/
GLenum QGLFramebufferObjectFormat::textureTarget() const
{
return d->target;
}
/*!
\since 4.6
Sets the internal format of a framebuffer object's texture or multisample
framebuffer object's color buffer to \a internalFormat.
\sa internalFormat()
*/
void QGLFramebufferObjectFormat::setInternalFormat(GLenum internalFormat)
{
d->internal_format = internalFormat;
}
/*!
\since 4.6
Returns the internal format of a framebuffer object's texture or
multisample framebuffer object's color buffer.
\sa setInternalFormat()
*/
GLenum QGLFramebufferObjectFormat::internalFormat() const
{
return d->internal_format;
}
class QGLFramebufferObjectPrivate
{
public:
QGLFramebufferObjectPrivate() : depth_stencil_buffer(0), valid(false), bound(false), ctx(0), previous_fbo(0) {}
~QGLFramebufferObjectPrivate() {}
void init(const QSize& sz, QGLFramebufferObject::Attachment attachment,
GLenum internal_format, GLenum texture_target, GLint samples = 0);
bool checkFramebufferStatus() const;
GLuint texture;
GLuint fbo;
GLuint depth_stencil_buffer;
GLuint color_buffer;
GLenum target;
QSize size;
QGLFramebufferObjectFormat format;
int samples;
uint valid : 1;
uint bound : 1;
QGLFramebufferObject::Attachment fbo_attachment;
QGLContext *ctx; // for Windows extension ptrs
GLuint previous_fbo;
};
bool QGLFramebufferObjectPrivate::checkFramebufferStatus() const
{
GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER_EXT);
switch(status) {
case GL_NO_ERROR:
case GL_FRAMEBUFFER_COMPLETE_EXT:
return true;
break;
case GL_FRAMEBUFFER_UNSUPPORTED_EXT:
qDebug("QGLFramebufferObject: Unsupported framebuffer format.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete attachment.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, missing attachment.");
break;
#ifdef GL_FRAMEBUFFER_INCOMPLETE_DUPLICATE_ATTACHMENT_EXT
case GL_FRAMEBUFFER_INCOMPLETE_DUPLICATE_ATTACHMENT_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, duplicate attachment.");
break;
#endif
case GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, attached images must have same dimensions.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_FORMATS_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, attached images must have same format.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, missing draw buffer.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, missing read buffer.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE_EXT:
qDebug("QGLFramebufferObject: Framebuffer incomplete, attachments must have same number of samples per pixel.");
break;
default:
qDebug() <<"QGLFramebufferObject: An undefined error has occurred: "<< status;
break;
}
return false;
}
void QGLFramebufferObjectPrivate::init(const QSize &sz, QGLFramebufferObject::Attachment attachment,
GLenum texture_target, GLenum internal_format, GLint samples)
{
ctx = const_cast<QGLContext *>(QGLContext::currentContext());
bool ext_detected = (QGLExtensions::glExtensions & QGLExtensions::FramebufferObject);
if (!ext_detected || (ext_detected && !qt_resolve_framebufferobject_extensions(ctx)))
return;
size = sz;
target = texture_target;
// texture dimensions
while (glGetError() != GL_NO_ERROR) {} // reset error state
glGenFramebuffers(1, &fbo);
glBindFramebuffer(GL_FRAMEBUFFER_EXT, fbo);
QT_CHECK_GLERROR();
// init texture
if (samples == 0) {
glGenTextures(1, &texture);
glBindTexture(target, texture);
glTexImage2D(target, 0, internal_format, size.width(), size.height(), 0,
GL_RGBA, GL_UNSIGNED_BYTE, NULL);
#ifndef QT_OPENGL_ES
glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
#else
glTexParameterf(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameterf(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameterf(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
#endif
glFramebufferTexture2D(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
target, texture, 0);
QT_CHECK_GLERROR();
valid = checkFramebufferStatus();
color_buffer = 0;
samples = 0;
} else {
GLint maxSamples;
glGetIntegerv(GL_MAX_SAMPLES_EXT, &maxSamples);
samples = qBound(1, int(samples), int(maxSamples));
glGenRenderbuffers(1, &color_buffer);
glBindRenderbuffer(GL_RENDERBUFFER_EXT, color_buffer);
if (glRenderbufferStorageMultisampleEXT) {
glRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER_EXT, samples,
internal_format, size.width(), size.height());
} else {
samples = 0;
glRenderbufferStorage(GL_RENDERBUFFER_EXT, internal_format,
size.width(), size.height());
}
glFramebufferRenderbuffer(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
GL_RENDERBUFFER_EXT, color_buffer);
QT_CHECK_GLERROR();
valid = checkFramebufferStatus();
if (valid)
glGetRenderbufferParameteriv(GL_RENDERBUFFER_EXT, GL_RENDERBUFFER_SAMPLES_EXT, &samples);
}
if (attachment == QGLFramebufferObject::CombinedDepthStencil
&& (QGLExtensions::glExtensions & QGLExtensions::PackedDepthStencil)) {
// depth and stencil buffer needs another extension
glGenRenderbuffers(1, &depth_stencil_buffer);
Q_ASSERT(!glIsRenderbuffer(depth_stencil_buffer));
glBindRenderbuffer(GL_RENDERBUFFER_EXT, depth_stencil_buffer);
Q_ASSERT(glIsRenderbuffer(depth_stencil_buffer));
if (samples != 0 && glRenderbufferStorageMultisampleEXT)
glRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER_EXT, samples,
GL_DEPTH24_STENCIL8_EXT, size.width(), size.height());
else
glRenderbufferStorage(GL_RENDERBUFFER_EXT,
GL_DEPTH24_STENCIL8_EXT, size.width(), size.height());
GLint i = 0;
glGetRenderbufferParameteriv(GL_RENDERBUFFER_EXT, GL_RENDERBUFFER_DEPTH_SIZE_EXT, &i);
glFramebufferRenderbuffer(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT,
GL_RENDERBUFFER_EXT, depth_stencil_buffer);
glFramebufferRenderbuffer(GL_FRAMEBUFFER_EXT, GL_STENCIL_ATTACHMENT_EXT,
GL_RENDERBUFFER_EXT, depth_stencil_buffer);
fbo_attachment = QGLFramebufferObject::CombinedDepthStencil;
valid = checkFramebufferStatus();
if (!valid)
glDeleteRenderbuffers(1, &depth_stencil_buffer);
} else if (attachment == QGLFramebufferObject::Depth
|| attachment == QGLFramebufferObject::CombinedDepthStencil)
{
glGenRenderbuffers(1, &depth_stencil_buffer);
Q_ASSERT(!glIsRenderbuffer(depth_stencil_buffer));
glBindRenderbuffer(GL_RENDERBUFFER_EXT, depth_stencil_buffer);
Q_ASSERT(glIsRenderbuffer(depth_stencil_buffer));
if (samples != 0 && glRenderbufferStorageMultisampleEXT) {
#ifdef QT_OPENGL_ES
#define GL_DEPTH_COMPONENT16 0x81A5
glRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER_EXT, samples,
GL_DEPTH_COMPONENT16, size.width(), size.height());
#else
glRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER_EXT, samples,
GL_DEPTH_COMPONENT, size.width(), size.height());
#endif
} else {
#ifdef QT_OPENGL_ES
#define GL_DEPTH_COMPONENT16 0x81A5
glRenderbufferStorage(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT16, size.width(), size.height());
#else
glRenderbufferStorage(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, size.width(), size.height());
#endif
}
GLint i = 0;
glGetRenderbufferParameteriv(GL_RENDERBUFFER_EXT, GL_RENDERBUFFER_DEPTH_SIZE_EXT, &i);
glFramebufferRenderbuffer(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT,
GL_RENDERBUFFER_EXT, depth_stencil_buffer);
fbo_attachment = QGLFramebufferObject::Depth;
valid = checkFramebufferStatus();
if (!valid)
glDeleteRenderbuffers(1, &depth_stencil_buffer);
} else {
fbo_attachment = QGLFramebufferObject::NoAttachment;
}
glBindFramebuffer(GL_FRAMEBUFFER_EXT, ctx->d_ptr->current_fbo);
if (!valid) {
if (color_buffer)
glDeleteRenderbuffers(1, &color_buffer);
else
glDeleteTextures(1, &texture);
glDeleteFramebuffers(1, &fbo);
}
QT_CHECK_GLERROR();
format.setTextureTarget(target);
format.setSamples(int(samples));
format.setAttachment(fbo_attachment);
format.setInternalFormat(internal_format);
}
/*!
\class QGLFramebufferObject
\brief The QGLFramebufferObject class encapsulates an OpenGL framebuffer object.
\since 4.2
\ingroup multimedia
The QGLFramebufferObject class encapsulates an OpenGL framebuffer
object, defined by the \c{GL_EXT_framebuffer_object} extension. In
addition it provides a rendering surface that can be painted on
with a QPainter, rendered to using native GL calls, or both. This
surface can be bound and used as a regular texture in your own GL
drawing code. By default, the QGLFramebufferObject class
generates a 2D GL texture (using the \c{GL_TEXTURE_2D} target),
which is used as the internal rendering target.
\bold{It is important to have a current GL context when creating a
QGLFramebufferObject, otherwise initialization will fail.}
OpenGL framebuffer objects and pbuffers (see
\l{QGLPixelBuffer}{QGLPixelBuffer}) can both be used to render to
offscreen surfaces, but there are a number of advantages with
using framebuffer objects instead of pbuffers:
\list 1
\o A framebuffer object does not require a separate rendering
context, so no context switching will occur when switching
rendering targets. There is an overhead involved in switching
targets, but in general it is cheaper than a context switch to a
pbuffer.
\o Rendering to dynamic textures (i.e. render-to-texture
functionality) works on all platforms. No need to do explicit copy
calls from a render buffer into a texture, as was necessary on
systems that did not support the \c{render_texture} extension.
\o It is possible to attach several rendering buffers (or texture
objects) to the same framebuffer object, and render to all of them
without doing a context switch.
\o The OpenGL framebuffer extension is a pure GL extension with no
system dependant WGL, CGL, or GLX parts. This makes using
framebuffer objects more portable.
\endlist
Note that you need to create a QGLFramebufferObject with more than one
sample per pixel for primitives to be antialiased when drawing using a
QPainter, unless if the QPainter::HighQualityAntialiasing render hint is
set. The QPainter::HighQualityAntialiasing render hint will enable
antialiasing as long as the \c{GL_ARB_fragment_program} extension is
present. To create a multisample framebuffer object you should use one of
the constructors that take a QGLFramebufferObject parameter, and set the
QGLFramebufferObject::samples() property to a non-zero value.
If you want to use a framebuffer object with multisampling enabled
as a texture, you first need to copy from it to a regular framebuffer
object using QGLContext::blitFramebuffer().
\sa {Framebuffer Object Example}
*/
/*!
\enum QGLFramebufferObject::Attachment
\since 4.3
This enum type is used to configure the depth and stencil buffers
attached to the framebuffer object when it is created.
\value NoAttachment No attachment is added to the framebuffer object. Note that the
OpenGL depth and stencil tests won't work when rendering to a
framebuffer object without any depth or stencil buffers.
This is the default value.
\value CombinedDepthStencil If the \c GL_EXT_packed_depth_stencil extension is present,
a combined depth and stencil buffer is attached.
If the extension is not present, only a depth buffer is attached.
\value Depth A depth buffer is attached to the framebuffer object.
\sa attachment()
*/
/*! \fn QGLFramebufferObject::QGLFramebufferObject(const QSize &size, GLenum target)
Constructs an OpenGL framebuffer object and binds a 2D GL texture
to the buffer of the size \a size. The texture is bound to the
\c GL_COLOR_ATTACHMENT0 target in the framebuffer object.
The \a target parameter is used to specify the GL texture
target. The default target is \c GL_TEXTURE_2D. Keep in mind that
\c GL_TEXTURE_2D textures must have a power of 2 width and height
(e.g. 256x512), unless you are using OpenGL 2.0 or higher.
By default, no depth and stencil buffers are attached. This behavior
can be toggled using one of the overloaded constructors.
The default internal texture format is \c GL_RGBA8.
It is important that you have a current GL context set when
creating the QGLFramebufferObject, otherwise the initialization
will fail.
\sa size(), texture(), attachment()
*/
#ifndef QT_OPENGL_ES
#define DEFAULT_FORMAT GL_RGBA8
#else
#define DEFAULT_FORMAT GL_RGBA
#endif
QGLFramebufferObject::QGLFramebufferObject(const QSize &size, GLenum target)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(size, NoAttachment, target, DEFAULT_FORMAT);
}
#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
QGLFramebufferObject::QGLFramebufferObject(const QSize &size, QMacCompatGLenum target)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(size, NoAttachment, target, DEFAULT_FORMAT);
}
#endif
/*! \overload
Constructs an OpenGL framebuffer object and binds a 2D GL texture
to the buffer of the given \a width and \a height.
\sa size(), texture()
*/
QGLFramebufferObject::QGLFramebufferObject(int width, int height, GLenum target)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(QSize(width, height), NoAttachment, target, DEFAULT_FORMAT);
}
/*! \overload
Constructs an OpenGL framebuffer object of the given \a size based on the
supplied \a format.
*/
QGLFramebufferObject::QGLFramebufferObject(const QSize &size, const QGLFramebufferObjectFormat &format)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(size, format.attachment(), format.textureTarget(), format.internalFormat(), format.samples());
}
/*! \overload
Constructs an OpenGL framebuffer object of the given \a width and \a height
based on the supplied \a format.
*/
QGLFramebufferObject::QGLFramebufferObject(int width, int height, const QGLFramebufferObjectFormat &format)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(QSize(width, height), format.attachment(), format.textureTarget(), format.internalFormat(), format.samples());
}
#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
QGLFramebufferObject::QGLFramebufferObject(int width, int height, QMacCompatGLenum target)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(QSize(width, height), NoAttachment, target, DEFAULT_FORMAT);
}
#endif
/*! \overload
Constructs an OpenGL framebuffer object and binds a texture to the
buffer of the given \a width and \a height.
The \a attachment parameter describes the depth/stencil buffer
configuration, \a target the texture target and \a internal_format
the internal texture format. The default texture target is \c
GL_TEXTURE_2D, while the default internal format is \c GL_RGBA8.
\sa size(), texture(), attachment()
*/
QGLFramebufferObject::QGLFramebufferObject(int width, int height, Attachment attachment,
GLenum target, GLenum internal_format)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(QSize(width, height), attachment, target, internal_format);
}
#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
QGLFramebufferObject::QGLFramebufferObject(int width, int height, Attachment attachment,
QMacCompatGLenum target, QMacCompatGLenum internal_format)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(QSize(width, height), attachment, target, internal_format);
}
#endif
/*! \overload
Constructs an OpenGL framebuffer object and binds a texture to the
buffer of the given \a size.
The \a attachment parameter describes the depth/stencil buffer
configuration, \a target the texture target and \a internal_format
the internal texture format. The default texture target is \c
GL_TEXTURE_2D, while the default internal format is \c GL_RGBA8.
\sa size(), texture(), attachment()
*/
QGLFramebufferObject::QGLFramebufferObject(const QSize &size, Attachment attachment,
GLenum target, GLenum internal_format)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(size, attachment, target, internal_format);
}
#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
QGLFramebufferObject::QGLFramebufferObject(const QSize &size, Attachment attachment,
QMacCompatGLenum target, QMacCompatGLenum internal_format)
: d_ptr(new QGLFramebufferObjectPrivate)
{
Q_D(QGLFramebufferObject);
d->init(size, attachment, target, internal_format);
}
#endif
/*!
\fn QGLFramebufferObject::~QGLFramebufferObject()
Destroys the framebuffer object and frees any allocated resources.
*/
QGLFramebufferObject::~QGLFramebufferObject()
{
Q_D(QGLFramebufferObject);
QGL_FUNC_CONTEXT;
if (isValid()
&& (d->ctx == QGLContext::currentContext()
|| qgl_share_reg()->checkSharing(d->ctx, QGLContext::currentContext())))
{
glDeleteTextures(1, &d->texture);
if (d->color_buffer)
glDeleteRenderbuffers(1, &d->color_buffer);
if (d->depth_stencil_buffer)
glDeleteRenderbuffers(1, &d->depth_stencil_buffer);
glDeleteFramebuffers(1, &d->fbo);
}
}
/*!
\fn bool QGLFramebufferObject::isValid() const
Returns true if the framebuffer object is valid.
The framebuffer can become invalid if the initialization process
fails, the user attaches an invalid buffer to the framebuffer
object, or a non-power of 2 width/height is specified as the
texture size if the texture target is \c{GL_TEXTURE_2D}.
*/
bool QGLFramebufferObject::isValid() const
{
Q_D(const QGLFramebufferObject);
return d->valid;
}
/*!
\fn bool QGLFramebufferObject::bind()
Switches rendering from the default, windowing system provided
framebuffer to this framebuffer object.
Returns true upon success, false otherwise.
Since 4.6: if another QGLFramebufferObject instance was already bound
to the current context, then its handle() will be remembered and
automatically restored when release() is called. This allows multiple
framebuffer rendering targets to be stacked up. It is important that
release() is called on the stacked framebuffer objects in the reverse
order of the calls to bind().
\sa release()
*/
bool QGLFramebufferObject::bind()
{
if (!isValid())
return false;
Q_D(QGLFramebufferObject);
QGL_FUNC_CONTEXT;
glBindFramebuffer(GL_FRAMEBUFFER_EXT, d->fbo);
d->bound = d->valid = d->checkFramebufferStatus();
const QGLContext *context = QGLContext::currentContext();
if (d->valid && context) {
// Save the previous setting to automatically restore in release().
if (context->d_ptr->current_fbo != d->fbo) {
d->previous_fbo = context->d_ptr->current_fbo;
context->d_ptr->current_fbo = d->fbo;
}
}
return d->valid;
}
/*!
\fn bool QGLFramebufferObject::release()
Switches rendering back to the default, windowing system provided
framebuffer.
Returns true upon success, false otherwise.
Since 4.6: if another QGLFramebufferObject instance was already bound
to the current context when bind() was called, then this function will
automatically re-bind it to the current context.
\sa bind()
*/
bool QGLFramebufferObject::release()
{
if (!isValid())
return false;
Q_D(QGLFramebufferObject);
QGL_FUNC_CONTEXT;
d->bound = false;
const QGLContext *context = QGLContext::currentContext();
if (context) {
// Restore the previous setting for stacked framebuffer objects.
if (d->previous_fbo != context->d_ptr->current_fbo) {
context->d_ptr->current_fbo = d->previous_fbo;
glBindFramebuffer(GL_FRAMEBUFFER_EXT, d->previous_fbo);
}
d->previous_fbo = 0;
}
return true;
}
/*!
\fn GLuint QGLFramebufferObject::texture() const
Returns the texture id for the texture attached as the default
rendering target in this framebuffer object. This texture id can
be bound as a normal texture in your own GL code.
If a multisample framebuffer object is used then the value returned
from this function will be invalid.
*/
GLuint QGLFramebufferObject::texture() const
{
Q_D(const QGLFramebufferObject);
return d->texture;
}
/*!
\fn QSize QGLFramebufferObject::size() const
Returns the size of the texture attached to this framebuffer
object.
*/
QSize QGLFramebufferObject::size() const
{
Q_D(const QGLFramebufferObject);
return d->size;
}
/*!
Returns the format of this framebuffer object.
*/
const QGLFramebufferObjectFormat &QGLFramebufferObject::format() const
{
Q_D(const QGLFramebufferObject);
return d->format;
}
/*!
\fn QImage QGLFramebufferObject::toImage() const
Returns the contents of this framebuffer object as a QImage.
*/
QImage QGLFramebufferObject::toImage() const
{
Q_D(const QGLFramebufferObject);
if (!d->valid)
return QImage();
const_cast<QGLFramebufferObject *>(this)->bind();
QImage image = qt_gl_read_framebuffer(d->size, d->ctx->format().alpha(), true);
const_cast<QGLFramebufferObject *>(this)->release();
return image;
}
#if !defined(QT_OPENGL_ES_1) && !defined(QT_OPENGL_ES_1_CL)
Q_GLOBAL_STATIC(QGL2PaintEngineEx, qt_buffer_2_engine)
#endif
#ifndef QT_OPENGL_ES_2
Q_GLOBAL_STATIC(QOpenGLPaintEngine, qt_buffer_engine)
#endif
/*! \reimp */
QPaintEngine *QGLFramebufferObject::paintEngine() const
{
#if defined(QT_OPENGL_ES_1) || defined(QT_OPENGL_ES_1_CL)
return qt_buffer_engine();
#elif defined(QT_OPENGL_ES_2)
return qt_buffer_2_engine();
#else
Q_D(const QGLFramebufferObject);
if (d->ctx->d_func()->internal_context || qt_gl_preferGL2Engine())
return qt_buffer_2_engine();
else
return qt_buffer_engine();
#endif
}
/*!
\fn bool QGLFramebufferObject::hasOpenGLFramebufferObjects()
Returns true if the OpenGL \c{GL_EXT_framebuffer_object} extension
is present on this system; otherwise returns false.
*/
bool QGLFramebufferObject::hasOpenGLFramebufferObjects()
{
QGLExtensions::init();
return (QGLExtensions::glExtensions & QGLExtensions::FramebufferObject);
}
/*!
\since 4.4
Draws the given texture, \a textureId, to the given target rectangle,
\a target, in OpenGL model space. The \a textureTarget should be a 2D
texture target.
The framebuffer object should be bound when calling this function.
Equivalent to the corresponding QGLContext::drawTexture().
*/
void QGLFramebufferObject::drawTexture(const QRectF &target, GLuint textureId, GLenum textureTarget)
{
Q_D(QGLFramebufferObject);
d->ctx->drawTexture(target, textureId, textureTarget);
}
#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
void QGLFramebufferObject::drawTexture(const QRectF &target, QMacCompatGLuint textureId, QMacCompatGLenum textureTarget)
{
Q_D(QGLFramebufferObject);
d->ctx->drawTexture(target, textureId, textureTarget);
}
#endif
/*!
\since 4.4
Draws the given texture, \a textureId, at the given \a point in OpenGL
model space. The \a textureTarget should be a 2D texture target.
The framebuffer object should be bound when calling this function.
Equivalent to the corresponding QGLContext::drawTexture().
*/
void QGLFramebufferObject::drawTexture(const QPointF &point, GLuint textureId, GLenum textureTarget)
{
Q_D(QGLFramebufferObject);
d->ctx->drawTexture(point, textureId, textureTarget);
}
#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
void QGLFramebufferObject::drawTexture(const QPointF &point, QMacCompatGLuint textureId, QMacCompatGLenum textureTarget)
{
Q_D(QGLFramebufferObject);
d->ctx->drawTexture(point, textureId, textureTarget);
}
#endif
extern int qt_defaultDpiX();
extern int qt_defaultDpiY();
/*! \reimp */
int QGLFramebufferObject::metric(PaintDeviceMetric metric) const
{
Q_D(const QGLFramebufferObject);
float dpmx = qt_defaultDpiX()*100./2.54;
float dpmy = qt_defaultDpiY()*100./2.54;
int w = d->size.width();
int h = d->size.height();
switch (metric) {
case PdmWidth:
return w;
case PdmHeight:
return h;
case PdmWidthMM:
return qRound(w * 1000 / dpmx);
case PdmHeightMM:
return qRound(h * 1000 / dpmy);
case PdmNumColors:
return 0;
case PdmDepth:
return 32;//d->depth;
case PdmDpiX:
return qRound(dpmx * 0.0254);
case PdmDpiY:
return qRound(dpmy * 0.0254);
case PdmPhysicalDpiX:
return qRound(dpmx * 0.0254);
case PdmPhysicalDpiY:
return qRound(dpmy * 0.0254);
default:
qWarning("QGLFramebufferObject::metric(), Unhandled metric type: %d.\n", metric);
break;
}
return 0;
}
/*!
\fn GLuint QGLFramebufferObject::handle() const
Returns the GL framebuffer object handle for this framebuffer
object (returned by the \c{glGenFrameBuffersEXT()} function). This
handle can be used to attach new images or buffers to the
framebuffer. The user is responsible for cleaning up and
destroying these objects.
*/
GLuint QGLFramebufferObject::handle() const
{
Q_D(const QGLFramebufferObject);
return d->fbo;
}
/*! \fn int QGLFramebufferObject::devType() const
\reimp
*/
/*!
Returns the status of the depth and stencil buffers attached to
this framebuffer object.
*/
QGLFramebufferObject::Attachment QGLFramebufferObject::attachment() const
{
Q_D(const QGLFramebufferObject);
if (d->valid)
return d->fbo_attachment;
return NoAttachment;
}
/*!
\since 4.5
Returns true if the framebuffer object is currently bound to a context,
otherwise false is returned.
*/
bool QGLFramebufferObject::isBound() const
{
Q_D(const QGLFramebufferObject);
return d->bound;
}
/*!
\fn bool QGLFramebufferObject::hasOpenGLFramebufferBlit()
\since 4.6
Returns true if the OpenGL \c{GL_EXT_framebuffer_blit} extension
is present on this system; otherwise returns false.
*/
bool QGLFramebufferObject::hasOpenGLFramebufferBlit()
{
QGLExtensions::init();
return (QGLExtensions::glExtensions & QGLExtensions::FramebufferBlit);
}
/*!
\since 4.6
Blits from the \a sourceRect rectangle in the \a source framebuffer
object to the \a targetRect rectangle in the \a target framebuffer object.
If \a source or \a target is 0, the default framebuffer will be used
instead of a framebuffer object as source or target respectively.
The \a buffers parameter should be a mask consisting of any combination of
COLOR_BUFFER_BIT, DEPTH_BUFFER_BIT, and STENCIL_BUFFER_BIT. Any buffer type
that is not present both in the source and target buffers is ignored.
The \a sourceRect and \a targetRect rectangles may have different sizes;
in this case \a buffers should not contain DEPTH_BUFFER_BIT or
STENCIL_BUFFER_BIT. The \a filter parameter should be set to GL_LINEAR or
GL_NEAREST, and specifies whether linear or nearest interpolation should
be used when scaling is performed.
If \a source equals \a target a copy is performed within the same buffer.
Results are undefined if the source and target rectangles overlap and
have different sizes. The sizes must also be the same if any of the
framebuffer objects are multisample framebuffers.
Note that the scissor test will restrict the blit area if enabled.
This function will have no effect unless hasOpenGLFramebufferBlit() returns
true.
*/
void QGLFramebufferObject::blitFramebuffer(QGLFramebufferObject *target, const QRect &targetRect,
QGLFramebufferObject *source, const QRect &sourceRect,
GLbitfield buffers,
GLenum filter)
{
if (!(QGLExtensions::glExtensions & QGLExtensions::FramebufferBlit))
return;
const QGLContext *ctx = QGLContext::currentContext();
if (!ctx)
return;
const int height = ctx->device()->height();
const int sh = source ? source->height() : height;
const int th = target ? target->height() : height;
const int sx0 = sourceRect.left();
const int sx1 = sourceRect.left() + sourceRect.width();
const int sy0 = sh - (sourceRect.top() + sourceRect.height());
const int sy1 = sh - sourceRect.top();
const int tx0 = targetRect.left();
const int tx1 = targetRect.left() + targetRect.width();
const int ty0 = th - (targetRect.top() + targetRect.height());
const int ty1 = th - targetRect.top();
glBindFramebuffer(GL_READ_FRAMEBUFFER_EXT, source ? source->handle() : 0);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER_EXT, target ? target->handle() : 0);
glBlitFramebufferEXT(sx0, sy0, sx1, sy1,
tx0, ty0, tx1, ty1,
buffers, filter);
glBindFramebuffer(GL_FRAMEBUFFER_EXT, ctx->d_ptr->current_fbo);
}
QT_END_NAMESPACE
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