summaryrefslogtreecommitdiffstats
path: root/src/extras/geometries/qspheregeometry.cpp
blob: 277d4fcb95fa63d8c41ecab51b096e627c6fb65b (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
/****************************************************************************
**
** Copyright (C) 2015 Klaralvdalens Datakonsult AB (KDAB).
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt3D 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 The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qspheregeometry.h"
#include "qspheregeometry_p.h"
#include <Qt3DRender/qbufferdatagenerator.h>
#include <Qt3DRender/qbuffer.h>
#include <Qt3DRender/qattribute.h>

#ifndef _USE_MATH_DEFINES
# define _USE_MATH_DEFINES // For MSVC
#endif

#include <qmath.h>

QT_BEGIN_NAMESPACE

using namespace Qt3DRender;

namespace  Qt3DExtras {

namespace {

QByteArray createSphereMeshVertexData(float radius, int rings, int slices)
{
    QByteArray bufferBytes;
    // vec3 pos, vec2 texCoord, vec3 normal, vec4 tangent
    const quint32 elementSize = 3 + 2 + 3 + 4;
    const quint32 stride = elementSize * sizeof(float);
    const int nVerts  = (slices + 1) * (rings + 1);
    bufferBytes.resize(stride * nVerts);

    float* fptr = reinterpret_cast<float*>(bufferBytes.data());

    const float dTheta = (M_PI * 2) / static_cast<float>( slices );
    const float dPhi = M_PI / static_cast<float>( rings );
    const float du = 1.0f / static_cast<float>( slices );
    const float dv = 1.0f / static_cast<float>( rings );

    // Iterate over latitudes (rings)
    for ( int lat = 0; lat < rings + 1; ++lat )
    {
        const float phi = M_PI_2 - static_cast<float>( lat ) * dPhi;
        const float cosPhi = qCos( phi );
        const float sinPhi = qSin( phi );
        const float v = 1.0f - static_cast<float>( lat ) * dv;

        // Iterate over longitudes (slices)
        for ( int lon = 0; lon < slices + 1; ++lon )
        {
            const float theta = static_cast<float>( lon ) * dTheta;
            const float cosTheta = qCos( theta );
            const float sinTheta = qSin( theta );
            const float u = static_cast<float>( lon ) * du;

            *fptr++ = radius * cosTheta * cosPhi;
            *fptr++ = radius * sinPhi;
            *fptr++ = radius * sinTheta * cosPhi;

            *fptr++ = u;
            *fptr++ = v;

            *fptr++   = cosTheta * cosPhi;
            *fptr++ = sinPhi;
            *fptr++ = sinTheta * cosPhi;

            *fptr++ = sinTheta;
            *fptr++ = 0.0;
            *fptr++ = -cosTheta;
            *fptr++ = 1.0;
        }
    }
    return bufferBytes;
}

QByteArray createSphereMeshIndexData(int rings, int slices)
{
    int faces = (slices * 2) * (rings - 2); // two tris per slice, for all middle rings
    faces += 2 * slices; // tri per slice for both top and bottom

    QByteArray indexBytes;
    const int indices = faces * 3;
    Q_ASSERT(indices < 65536);
    indexBytes.resize(indices * sizeof(quint16));
    quint16 *indexPtr = reinterpret_cast<quint16*>(indexBytes.data());

    // top cap
    {
        const int nextRingStartIndex = slices + 1;
        for ( int j = 0; j < slices; ++j )
        {
            *indexPtr++ = nextRingStartIndex + j;
            *indexPtr++ = 0;
            *indexPtr++ = nextRingStartIndex + j + 1;
        }
    }

    for ( int i = 1; i < (rings - 1); ++i )
    {
        const int ringStartIndex = i * ( slices + 1 );
        const int nextRingStartIndex = ( i + 1 ) * ( slices + 1 );

        for ( int j = 0; j < slices; ++j )
        {
            // Split the quad into two triangles
            *indexPtr++ = ringStartIndex + j;
            *indexPtr++ = ringStartIndex + j + 1;
            *indexPtr++ = nextRingStartIndex + j;
            *indexPtr++ = nextRingStartIndex + j;
            *indexPtr++ = ringStartIndex + j + 1;
            *indexPtr++ = nextRingStartIndex + j + 1;
        }
    }

    // bottom cap
    {
        const int ringStartIndex = (rings - 1) * ( slices + 1);
        const int nextRingStartIndex = (rings) * ( slices + 1);
        for ( int j = 0; j < slices; ++j )
        {
            *indexPtr++ = ringStartIndex + j + 1;
            *indexPtr++ = nextRingStartIndex;
            *indexPtr++ = ringStartIndex + j;
        }
    }

    return indexBytes;
}

} // anonymous

class SphereVertexDataFunctor : public QBufferDataGenerator
{
public:
    SphereVertexDataFunctor(int rings, int slices, float radius)
        : m_rings(rings)
        , m_slices(slices)
        , m_radius(radius)
    {
    }

    QByteArray operator ()() Q_DECL_OVERRIDE
    {
        return createSphereMeshVertexData(m_radius, m_rings, m_slices);
    }

    bool operator ==(const QBufferDataGenerator &other) const Q_DECL_OVERRIDE
    {
        const SphereVertexDataFunctor *otherFunctor = functor_cast<SphereVertexDataFunctor>(&other);
        if (otherFunctor != nullptr)
            return (otherFunctor->m_rings == m_rings &&
                    otherFunctor->m_slices == m_slices &&
                    otherFunctor->m_radius == m_radius);
        return false;
    }

    QT3D_FUNCTOR(SphereVertexDataFunctor)

private:
    int m_rings;
    int m_slices;
    float m_radius;
};

class SphereIndexDataFunctor : public QBufferDataGenerator
{
public:
    SphereIndexDataFunctor(int rings, int slices)
        : m_rings(rings)
        , m_slices(slices)
    {
    }

    QByteArray operator ()() Q_DECL_OVERRIDE
    {
        return createSphereMeshIndexData(m_rings, m_slices);
    }

    bool operator ==(const QBufferDataGenerator &other) const Q_DECL_OVERRIDE
    {
        const SphereIndexDataFunctor *otherFunctor = functor_cast<SphereIndexDataFunctor>(&other);
        if (otherFunctor != nullptr)
            return (otherFunctor->m_rings == m_rings &&
                    otherFunctor->m_slices == m_slices);
        return false;
    }

    QT3D_FUNCTOR(SphereIndexDataFunctor)

private:
    int m_rings;
    int m_slices;
};

QSphereGeometryPrivate::QSphereGeometryPrivate()
    : QGeometryPrivate()
    , m_generateTangents(false)
    , m_rings(16)
    , m_slices(16)
    , m_radius(1.0f)
    , m_positionAttribute(nullptr)
    , m_normalAttribute(nullptr)
    , m_texCoordAttribute(nullptr)
    , m_tangentAttribute(nullptr)
    , m_indexAttribute(nullptr)
    , m_vertexBuffer(nullptr)
    , m_indexBuffer(nullptr)
{
}

void QSphereGeometryPrivate::init()
{
    Q_Q(QSphereGeometry);
    m_positionAttribute = new QAttribute(q);
    m_normalAttribute = new QAttribute(q);
    m_texCoordAttribute = new QAttribute(q);
    m_tangentAttribute = new QAttribute(q);
    m_indexAttribute = new QAttribute(q);
    m_vertexBuffer = new Qt3DRender::QBuffer(Qt3DRender::QBuffer::VertexBuffer, q);
    m_indexBuffer = new Qt3DRender::QBuffer(Qt3DRender::QBuffer::IndexBuffer, q);

    // vec3 pos, vec2 tex, vec3 normal, vec4 tangent
    const quint32 elementSize = 3 + 2 + 3 + 4;
    const quint32 stride = elementSize * sizeof(float);
    const int nVerts = (m_slices + 1) * (m_rings + 1);
    const int faces = (m_slices * 2) * (m_rings - 2) + (2 * m_slices);

    m_positionAttribute->setName(QAttribute::defaultPositionAttributeName());
    m_positionAttribute->setVertexBaseType(QAttribute::Float);
    m_positionAttribute->setVertexSize(3);
    m_positionAttribute->setAttributeType(QAttribute::VertexAttribute);
    m_positionAttribute->setBuffer(m_vertexBuffer);
    m_positionAttribute->setByteStride(stride);
    m_positionAttribute->setCount(nVerts);

    m_texCoordAttribute->setName(QAttribute::defaultTextureCoordinateAttributeName());
    m_texCoordAttribute->setVertexBaseType(QAttribute::Float);
    m_texCoordAttribute->setVertexSize(2);
    m_texCoordAttribute->setAttributeType(QAttribute::VertexAttribute);
    m_texCoordAttribute->setBuffer(m_vertexBuffer);
    m_texCoordAttribute->setByteStride(stride);
    m_texCoordAttribute->setByteOffset(3 * sizeof(float));
    m_texCoordAttribute->setCount(nVerts);

    m_normalAttribute->setName(QAttribute::defaultNormalAttributeName());
    m_normalAttribute->setVertexBaseType(QAttribute::Float);
    m_normalAttribute->setVertexSize(3);
    m_normalAttribute->setAttributeType(QAttribute::VertexAttribute);
    m_normalAttribute->setBuffer(m_vertexBuffer);
    m_normalAttribute->setByteStride(stride);
    m_normalAttribute->setByteOffset(5 * sizeof(float));
    m_normalAttribute->setCount(nVerts);

    m_tangentAttribute->setName(QAttribute::defaultTangentAttributeName());
    m_tangentAttribute->setVertexBaseType(QAttribute::Float);
    m_tangentAttribute->setVertexSize(4);
    m_tangentAttribute->setAttributeType(QAttribute::VertexAttribute);
    m_tangentAttribute->setBuffer(m_vertexBuffer);
    m_tangentAttribute->setByteStride(stride);
    m_tangentAttribute->setByteOffset(8 * sizeof(float));
    m_tangentAttribute->setCount(nVerts);

    m_indexAttribute->setAttributeType(QAttribute::IndexAttribute);
    m_indexAttribute->setVertexBaseType(QAttribute::UnsignedShort);
    m_indexAttribute->setBuffer(m_indexBuffer);

    m_indexAttribute->setCount(faces * 3);

    m_vertexBuffer->setDataGenerator(QSharedPointer<SphereVertexDataFunctor>::create(m_rings, m_slices, m_radius));
    m_indexBuffer->setDataGenerator(QSharedPointer<SphereIndexDataFunctor>::create(m_rings, m_slices));

    q->addAttribute(m_positionAttribute);
    q->addAttribute(m_texCoordAttribute);
    q->addAttribute(m_normalAttribute);
    if (m_generateTangents)
        q->addAttribute(m_tangentAttribute);
    q->addAttribute(m_indexAttribute);
}

/*!
 * \qmltype SphereGeometry
 * \instantiates Qt3DExtras::QSphereGeometry
 * \inqmlmodule Qt3D.Extras
 * \brief SphereGeometry allows creation of a sphere in 3D space.
 *
 * The SphereGeometry type is most commonly used internally by the SphereMesh type
 * but can also be used in custom GeometryRenderer types.
 */

/*!
 * \qmlproperty int SphereGeometry::rings
 *
 * Holds the number of rings in the sphere.
 */

/*!
 * \qmlproperty int SphereGeometry::slices
 *
 * Holds the number of slices in the sphere.
 */

/*!
 * \qmlproperty real SphereGeometry::radius
 *
 * Holds the radius of the sphere.
 */

/*!
 * \qmlproperty bool SphereGeometry::generateTangents
 *
 * Holds the value of the automatic tangent vectors generation flag.
 * Tangent vectors are orthogonal to normal vectors.
 */

/*!
 * \qmlproperty Attribute SphereGeometry::positionAttribute
 *
 * Holds the geometry position attribute.
 */

/*!
 * \qmlproperty Attribute SphereGeometry::normalAttribute
 *
 * Holds the geometry normal attribute.
 */

/*!
 * \qmlproperty Attribute SphereGeometry::texCoordAttribute
 *
 * Holds the geometry texture coordinate attribute.
 */

/*!
 * \qmlproperty Attribute SphereGeometry::tangentAttribute
 *
 * Holds the geometry tangent attribute.
 */

/*!
 * \qmlproperty Attribute SphereGeometry::indexAttribute
 *
 * Holds the geometry index attribute.
 */

/*!
 * \class Qt3DExtras::QSphereGeometry
 * \inmodule Qt3DExtras
 * \brief The QSphereGeometry class allows creation of a sphere in 3D space.
 * \since 5.7
 * \ingroup geometries
 * \inherits Qt3DRender::QGeometry
 *
 * The QSphereGeometry class is most commonly used internally by the QSphereMesh
 * but can also be used in custom Qt3DRender::QGeometryRenderer subclasses.
 */

/*!
 * Constructs a new QSphereGeometry with \a parent.
 */
QSphereGeometry::QSphereGeometry(QNode *parent)
    : QGeometry(*new QSphereGeometryPrivate(), parent)
{
    Q_D(QSphereGeometry);
    d->init();
}

/*!
 * \internal
 */
QSphereGeometry::QSphereGeometry(QSphereGeometryPrivate &dd, QNode *parent)
    : QGeometry(dd, parent)
{
    Q_D(QSphereGeometry);
    d->init();
}

/*!
 * \internal
 */
QSphereGeometry::~QSphereGeometry()
{
}

/*!
 * Updates vertices based on rings, slices, and radius properties
 */
void QSphereGeometry::updateVertices()
{
    Q_D(QSphereGeometry);
    const int nVerts = (d->m_slices + 1) * (d->m_rings + 1);
    d->m_positionAttribute->setCount(nVerts);
    d->m_texCoordAttribute->setCount(nVerts);
    d->m_normalAttribute->setCount(nVerts);
    d->m_tangentAttribute->setCount(nVerts);
    d->m_vertexBuffer->setDataGenerator(QSharedPointer<SphereVertexDataFunctor>::create(d->m_rings, d->m_slices, d->m_radius));
}

/*!
 * Updates indices based on rings and slices properties.
 */
void QSphereGeometry::updateIndices()
{
    Q_D(QSphereGeometry);
    const int faces = (d->m_slices * 2) * (d->m_rings - 2) + (2 * d->m_slices);
    d->m_indexAttribute->setCount(faces * 3);
    d->m_indexBuffer->setDataGenerator(QSharedPointer<SphereIndexDataFunctor>::create(d->m_rings, d->m_slices));

}

void QSphereGeometry::setRings(int rings)
{
    Q_D(QSphereGeometry);
    if (rings != d->m_rings) {
        d->m_rings = rings;
        updateVertices();
        updateIndices();
        emit ringsChanged(rings);
    }
}

void QSphereGeometry::setSlices(int slices)
{
    Q_D(QSphereGeometry);
    if (slices != d->m_slices) {
        d->m_slices = slices;
        updateVertices();
        updateIndices();
        emit slicesChanged(slices);
    }
}

void QSphereGeometry::setRadius(float radius)
{
    Q_D(QSphereGeometry);
    if (radius != d->m_radius) {
        d->m_radius = radius;
        updateVertices();
        emit radiusChanged(radius);
    }
}

void QSphereGeometry::setGenerateTangents(bool gen)
{
    Q_D(QSphereGeometry);
    if (d->m_generateTangents != gen) {
        if (d->m_generateTangents)
            removeAttribute(d->m_tangentAttribute);
        d->m_generateTangents = gen;
        if (d->m_generateTangents)
            addAttribute(d->m_tangentAttribute);
        emit generateTangentsChanged(gen);
    }
}

/*!
 * \property QSphereGeometry::generateTangents
 *
 * Holds the value of the automatic tangent vectors generation flag.
 * Tangent vectors are orthogonal to normal vectors.
 */
bool QSphereGeometry::generateTangents() const
{
    Q_D(const QSphereGeometry);
    return d->m_generateTangents;
}

/*!
 * \property QSphereGeometry::rings
 *
 * Holds the number of rings in the sphere.
 */
int QSphereGeometry::rings() const
{
    Q_D(const QSphereGeometry);
    return d->m_rings;
}

/*!
 * \property QSphereGeometry::slices
 *
 * Holds the number of slices in the sphere.
 */
int QSphereGeometry::slices() const
{
    Q_D(const QSphereGeometry);
    return d->m_slices;
}

/*!
 * \property QSphereGeometry::radius
 *
 * Holds the radius of the sphere.
 */
float QSphereGeometry::radius() const
{
    Q_D(const QSphereGeometry);
    return d->m_radius;
}

/*!
 * \property QSphereGeometry::positionAttribute
 *
 * Holds the geometry position attribute.
 */
QAttribute *QSphereGeometry::positionAttribute() const
{
    Q_D(const QSphereGeometry);
    return d->m_positionAttribute;
}

/*!
 * \property QSphereGeometry::normalAttribute
 *
 * Holds the geometry normal attribute.
 */
QAttribute *QSphereGeometry::normalAttribute() const
{
    Q_D(const QSphereGeometry);
    return d->m_normalAttribute;
}

/*!
 * \property QSphereGeometry::texCoordAttribute
 *
 * Holds the geometry texture coordinate attribute.
 */
QAttribute *QSphereGeometry::texCoordAttribute() const
{
    Q_D(const QSphereGeometry);
    return d->m_texCoordAttribute;
}

/*!
 * \property QSphereGeometry::tangentAttribute
 *
 * Holds the geometry tangent attribute.
 */
QAttribute *QSphereGeometry::tangentAttribute() const
{
    Q_D(const QSphereGeometry);
    return d->m_tangentAttribute;
}

/*!
 * \property QSphereGeometry::indexAttribute
 *
 * Holds the geometry index attribute.
 */
QAttribute *QSphereGeometry::indexAttribute() const
{
    Q_D(const QSphereGeometry);
    return d->m_indexAttribute;
}

} //  Qt3DExtras

QT_END_NAMESPACE