summaryrefslogtreecommitdiffstats
path: root/src/opengl/qglpixelbuffer.cpp
blob: fab6efc8e53b5bd7bc2f61ec9818caf991a88b71 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** 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 Technology Preview License Agreement accompanying
** this package.
**
** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

/*!
    \class QGLPixelBuffer
    \brief The QGLPixelBuffer class encapsulates an OpenGL pbuffer.
    \since 4.1

    \ingroup painting-3D

    Rendering into a pbuffer is normally done using full hardware
    acceleration. This can be significantly faster than rendering
    into a QPixmap.

    There are three approaches to using this class:

    \list 1
    \o \bold{We can draw into the pbuffer and convert it to a QImage
       using toImage().} This is normally much faster than calling
       QGLWidget::renderPixmap().

    \o \bold{We can draw into the pbuffer and copy the contents into
       an OpenGL texture using updateDynamicTexture().} This allows
       us to create dynamic textures and works on all systems
       with pbuffer support.

    \o \bold{On systems that support it, we can bind the pbuffer to
       an OpenGL texture.} The texture is then updated automatically
       when the pbuffer contents change, eliminating the need for
       additional copy operations. This is supported only on Windows
       and Mac OS X systems that provide the \c render_texture
       extension.
    \endlist

    Pbuffers are provided by the OpenGL \c pbuffer extension; call
    hasOpenGLPbuffer() to find out if the system provides pbuffers.

    \sa {opengl/pbuffers}{Pbuffers Example}
*/

#include <QtCore/qglobal.h>

#if !defined(QT_OPENGL_ES_1) && !defined(QT_OPENGL_ES_1_CL)
#include <private/qpaintengineex_opengl2_p.h>
#endif

#include <qglpixelbuffer.h>
#include <private/qglpixelbuffer_p.h>
#include <qimage.h>

#ifndef QT_OPENGL_ES_2
#include <private/qpaintengine_opengl_p.h>
#endif

QT_BEGIN_NAMESPACE

#if !defined(QT_OPENGL_ES_2)
extern void qgl_cleanup_glyph_cache(QGLContext *);
#else
void qgl_cleanup_glyph_cache(QGLContext *) {}
#endif

extern QImage qt_gl_read_framebuffer(const QSize&, bool, bool);


QGLContext* QGLPBufferGLPaintDevice::context() const
{
    return pbuf->d_func()->qctx;
}

void QGLPBufferGLPaintDevice::endPaint() {
    glFlush();
    QGLPaintDevice::endPaint();
}

void QGLPBufferGLPaintDevice::setPBuffer(QGLPixelBuffer* pb)
{
    pbuf = pb;
}

void QGLPixelBufferPrivate::common_init(const QSize &size, const QGLFormat &format, QGLWidget *shareWidget)
{
    Q_Q(QGLPixelBuffer);
    if(init(size, format, shareWidget)) {
        req_size = size;
        req_format = format;
        req_shareWidget = shareWidget;
        invalid = false;
        qctx = new QGLContext(format);
        qctx->d_func()->sharing = (shareWidget != 0);
        if (shareWidget != 0 && shareWidget->d_func()->glcx) {
            QGLContextGroup::addShare(qctx, shareWidget->d_func()->glcx);
            shareWidget->d_func()->glcx->d_func()->sharing = true;
        }

        glDevice.setPBuffer(q);
        qctx->d_func()->paintDevice = q;
        qctx->d_func()->valid = true;
#if defined(Q_WS_WIN) && !defined(QT_OPENGL_ES)
        qctx->d_func()->dc = dc;
        qctx->d_func()->rc = ctx;
#elif (defined(Q_WS_X11) && !defined(QT_OPENGL_ES))
        qctx->d_func()->cx = ctx;
        qctx->d_func()->pbuf = (void *) pbuf;
        qctx->d_func()->vi = 0;
#elif defined(Q_WS_MAC)
        qctx->d_func()->cx = ctx;
        qctx->d_func()->vi = 0;
#elif defined(QT_OPENGL_ES)
        qctx->d_func()->eglContext = ctx;
        qctx->d_func()->eglSurface = pbuf;
#endif
    }
}

/*!
    Constructs an OpenGL pbuffer of the given \a size. If no \a
    format is specified, the \l{QGLFormat::defaultFormat()}{default
    format} is used. If the \a shareWidget parameter points to a
    valid QGLWidget, the pbuffer will share its context with \a
    shareWidget.

    If you intend to bind this pbuffer as a dynamic texture, the width
    and height components of \c size must be powers of two (e.g., 512
    x 128).

    \sa size(), format()
*/
QGLPixelBuffer::QGLPixelBuffer(const QSize &size, const QGLFormat &format, QGLWidget *shareWidget)
    : d_ptr(new QGLPixelBufferPrivate(this))
{
    Q_D(QGLPixelBuffer);
    d->common_init(size, format, shareWidget);
}


/*! \overload

    Constructs an OpenGL pbuffer with the \a width and \a height. If
    no \a format is specified, the
    \l{QGLFormat::defaultFormat()}{default format} is used. If the \a
    shareWidget parameter points to a valid QGLWidget, the pbuffer
    will share its context with \a shareWidget.

    If you intend to bind this pbuffer as a dynamic texture, the width
    and height components of \c size must be powers of two (e.g., 512
    x 128).

    \sa size(), format()
*/
QGLPixelBuffer::QGLPixelBuffer(int width, int height, const QGLFormat &format, QGLWidget *shareWidget)
    : d_ptr(new QGLPixelBufferPrivate(this))
{
    Q_D(QGLPixelBuffer);
    d->common_init(QSize(width, height), format, shareWidget);
}


/*! \fn QGLPixelBuffer::~QGLPixelBuffer()

    Destroys the pbuffer and frees any allocated resources.
*/
QGLPixelBuffer::~QGLPixelBuffer()
{
    Q_D(QGLPixelBuffer);

    // defined in qpaintengine_opengl.cpp
    QGLContext *current = const_cast<QGLContext *>(QGLContext::currentContext());
    if (current != d->qctx)
        makeCurrent();
    qgl_cleanup_glyph_cache(d->qctx);
    d->cleanup();
    delete d->qctx;
    if (current && current != d->qctx)
        current->makeCurrent();
}

/*! \fn bool QGLPixelBuffer::makeCurrent()

    Makes this pbuffer the current OpenGL rendering context. Returns
    true on success; otherwise returns false.

    \sa QGLContext::makeCurrent(), doneCurrent()
*/

bool QGLPixelBuffer::makeCurrent()
{
    Q_D(QGLPixelBuffer);
    if (d->invalid)
        return false;
    d->qctx->makeCurrent();
    return true;
}

/*! \fn bool QGLPixelBuffer::doneCurrent()

    Makes no context the current OpenGL context. Returns true on
    success; otherwise returns false.
*/

bool QGLPixelBuffer::doneCurrent()
{
    Q_D(QGLPixelBuffer);
    if (d->invalid)
        return false;
    d->qctx->doneCurrent();
    return true;
}

/*!
    Generates and binds a 2D GL texture that is the same size as the
    pbuffer, and returns the texture's ID. This can be used in
    conjunction with bindToDynamicTexture() and
    updateDynamicTexture().

    \sa size()
*/

#if (defined(Q_WS_X11) || defined(Q_WS_WIN)) && !defined(QT_OPENGL_ES)
GLuint QGLPixelBuffer::generateDynamicTexture() const
{
    Q_D(const QGLPixelBuffer);
    GLuint texture;
    glGenTextures(1, &texture);
    glBindTexture(GL_TEXTURE_2D, texture);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, d->req_size.width(), d->req_size.height(), 0, GL_RGBA, GL_FLOAT, 0);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    return texture;
}
#endif

/*! \fn bool QGLPixelBuffer::bindToDynamicTexture(GLuint texture_id)

    Binds the texture specified by \a texture_id to this pbuffer.
    Returns true on success; otherwise returns false.

    The texture must be of the same size and format as the pbuffer.

    To unbind the texture, call releaseFromDynamicTexture(). While
    the texture is bound, it is updated automatically when the
    pbuffer contents change, eliminating the need for additional copy
    operations.

    Example:

    \snippet doc/src/snippets/code/src_opengl_qglpixelbuffer.cpp 0

    \warning This function uses the \c {render_texture} extension,
    which is currently not supported under X11. An alternative that
    works on all systems (including X11) is to manually copy the
    pbuffer contents to a texture using updateDynamicTexture().

    \warning For the bindToDynamicTexture() call to succeed on the
    Mac OS X, the pbuffer needs a shared context, i.e. the
    QGLPixelBuffer must be created with a share widget.

    \sa generateDynamicTexture(), releaseFromDynamicTexture()
*/

/*! \fn void QGLPixelBuffer::releaseFromDynamicTexture()

    Releases the pbuffer from any previously bound texture.

    \sa bindToDynamicTexture()
*/

/*! \fn bool QGLPixelBuffer::hasOpenGLPbuffers()

    Returns true if the OpenGL \c pbuffer extension is present on
    this system; otherwise returns false.
*/

/*!
    Copies the pbuffer contents into the texture specified with \a
    texture_id.

    The texture must be of the same size and format as the pbuffer.

    Example:

    \snippet doc/src/snippets/code/src_opengl_qglpixelbuffer.cpp 1

    An alternative on Windows and Mac OS X systems that support the
    \c render_texture extension is to use bindToDynamicTexture() to
    get dynamic updates of the texture.

    \sa generateDynamicTexture(), bindToDynamicTexture()
*/
void QGLPixelBuffer::updateDynamicTexture(GLuint texture_id) const
{
    Q_D(const QGLPixelBuffer);
    if (d->invalid)
        return;
    glBindTexture(GL_TEXTURE_2D, texture_id);
#ifndef QT_OPENGL_ES
    glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 0, 0, d->req_size.width(), d->req_size.height(), 0);
#else
    glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 0, 0, d->req_size.width(), d->req_size.height(), 0);
#endif
}

#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
void QGLPixelBuffer::updateDynamicTexture(QMacCompatGLuint texture_id) const
{
    updateDynamicTexture(GLuint(texture_id));
}
#endif

/*!
    Returns the size of the pbuffer.
*/
QSize QGLPixelBuffer::size() const
{
    Q_D(const QGLPixelBuffer);
    return d->req_size;
}

/*!
    Returns the contents of the pbuffer as a QImage.
*/
QImage QGLPixelBuffer::toImage() const
{
    Q_D(const QGLPixelBuffer);
    if (d->invalid)
        return QImage();

    const_cast<QGLPixelBuffer *>(this)->makeCurrent();
    return qt_gl_read_framebuffer(d->req_size, d->format.alpha(), true);
}

/*!
    Returns the native pbuffer handle.
*/
Qt::HANDLE QGLPixelBuffer::handle() const
{
    Q_D(const QGLPixelBuffer);
    if (d->invalid)
        return 0;
    return (Qt::HANDLE) d->pbuf;
}

/*!
    Returns true if this pbuffer is valid; otherwise returns false.
*/
bool QGLPixelBuffer::isValid() const
{
    Q_D(const QGLPixelBuffer);
    return !d->invalid;
}

#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 *QGLPixelBuffer::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
    if (qt_gl_preferGL2Engine())
        return qt_buffer_2_engine();
    else
        return qt_buffer_engine();
#endif
}

extern int qt_defaultDpiX();
extern int qt_defaultDpiY();

/*! \reimp */
int QGLPixelBuffer::metric(PaintDeviceMetric metric) const
{
    Q_D(const QGLPixelBuffer);

    float dpmx = qt_defaultDpiX()*100./2.54;
    float dpmy = qt_defaultDpiY()*100./2.54;
    int w = d->req_size.width();
    int h = d->req_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("QGLPixelBuffer::metric(), Unhandled metric type: %d\n", metric);
        break;
    }
    return 0;
}

/*!
    Generates and binds a 2D GL texture to the current context, based
    on \a image. The generated texture id is returned and can be used
    in later glBindTexture() calls.

    The \a target parameter specifies the texture target.

    Equivalent to calling QGLContext::bindTexture().

    \sa deleteTexture()
*/
GLuint QGLPixelBuffer::bindTexture(const QImage &image, GLenum target)
{
    Q_D(QGLPixelBuffer);
#ifndef QT_OPENGL_ES
    return d->qctx->bindTexture(image, target, GLint(GL_RGBA8));
#else
    return d->qctx->bindTexture(image, target, GL_RGBA);
#endif
}

#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
GLuint QGLPixelBuffer::bindTexture(const QImage &image, QMacCompatGLenum target)
{
    Q_D(QGLPixelBuffer);
    return d->qctx->bindTexture(image, target, QMacCompatGLint(GL_RGBA8));
}
#endif

/*! \overload

    Generates and binds a 2D GL texture based on \a pixmap.

    Equivalent to calling QGLContext::bindTexture().

    \sa deleteTexture()
*/
GLuint QGLPixelBuffer::bindTexture(const QPixmap &pixmap, GLenum target)
{
    Q_D(QGLPixelBuffer);
#ifndef QT_OPENGL_ES
    return d->qctx->bindTexture(pixmap, target, GLint(GL_RGBA8));
#else
    return d->qctx->bindTexture(pixmap, target, GL_RGBA);
#endif
}

#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
GLuint QGLPixelBuffer::bindTexture(const QPixmap &pixmap, QMacCompatGLenum target)
{
    Q_D(QGLPixelBuffer);
    return d->qctx->bindTexture(pixmap, target, QMacCompatGLint(GL_RGBA8));
}
#endif

/*! \overload

    Reads the DirectDrawSurface (DDS) compressed file \a fileName and
    generates a 2D GL texture from it.

    Equivalent to calling QGLContext::bindTexture().

    \sa deleteTexture()
*/
GLuint QGLPixelBuffer::bindTexture(const QString &fileName)
{
    Q_D(QGLPixelBuffer);
    return d->qctx->bindTexture(fileName);
}

/*!
    Removes the texture identified by \a texture_id from the texture cache.

    Equivalent to calling QGLContext::deleteTexture().
 */
void QGLPixelBuffer::deleteTexture(GLuint texture_id)
{
    Q_D(QGLPixelBuffer);
    d->qctx->deleteTexture(texture_id);
}

#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
void QGLPixelBuffer::deleteTexture(QMacCompatGLuint texture_id)
{
    Q_D(QGLPixelBuffer);
    d->qctx->deleteTexture(texture_id);
}
#endif

/*!
    \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.

    Equivalent to the corresponding QGLContext::drawTexture().
*/
void QGLPixelBuffer::drawTexture(const QRectF &target, GLuint textureId, GLenum textureTarget)
{
    Q_D(QGLPixelBuffer);
    d->qctx->drawTexture(target, textureId, textureTarget);
}

#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
void QGLPixelBuffer::drawTexture(const QRectF &target, QMacCompatGLuint textureId, QMacCompatGLenum textureTarget)
{
    Q_D(QGLPixelBuffer);
    d->qctx->drawTexture(target, textureId, textureTarget);
}
#endif

/*!
    \since 4.4

    Draws the given texture, \a textureId, at the given \a point in OpenGL model
    space. The textureTarget parameter should be a 2D texture target.

    Equivalent to the corresponding QGLContext::drawTexture().
*/
void QGLPixelBuffer::drawTexture(const QPointF &point, GLuint textureId, GLenum textureTarget)
{
    Q_D(QGLPixelBuffer);
    d->qctx->drawTexture(point, textureId, textureTarget);
}

#ifdef Q_MAC_COMPAT_GL_FUNCTIONS
/*! \internal */
void QGLPixelBuffer::drawTexture(const QPointF &point, QMacCompatGLuint textureId, QMacCompatGLenum textureTarget)
{
    Q_D(QGLPixelBuffer);
    d->qctx->drawTexture(point, textureId, textureTarget);
}
#endif

/*!
    Returns the format of the pbuffer. The format may be different
    from the one that was requested.
*/
QGLFormat QGLPixelBuffer::format() const
{
    Q_D(const QGLPixelBuffer);
    return d->format;
}

/*! \fn int QGLPixelBuffer::devType() const
    \internal
*/

QT_END_NAMESPACE