1// Copyright (C) 2015 Klaralvdalens Datakonsult AB (KDAB).
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#include "qplanegeometry.h"
5#include "qplanegeometry_p.h"
6
7#include <Qt3DCore/qattribute.h>
8#include <Qt3DCore/qbuffer.h>
9
10#include <limits>
11
12QT_BEGIN_NAMESPACE
13
14
15namespace Qt3DExtras {
16
17using namespace Qt3DCore;
18
19namespace {
20
21QByteArray createPlaneVertexData(float w, float h, const QSize &resolution, bool mirrored)
22{
23 Q_ASSERT(w > 0.0f);
24 Q_ASSERT(h > 0.0f);
25 Q_ASSERT(resolution.width() >= 2);
26 Q_ASSERT(resolution.height() >= 2);
27
28 const int nVerts = resolution.width() * resolution.height();
29
30 // Populate a buffer with the interleaved per-vertex data with
31 // vec3 pos, vec2 texCoord, vec3 normal, vec4 tangent
32 const quint32 elementSize = 3 + 2 + 3 + 4;
33 const quint32 stride = elementSize * sizeof(float);
34 QByteArray bufferBytes;
35 bufferBytes.resize(size: stride * nVerts);
36 float* fptr = reinterpret_cast<float*>(bufferBytes.data());
37
38 const float x0 = -w / 2.0f;
39 const float z0 = -h / 2.0f;
40 const float dx = w / (resolution.width() - 1);
41 const float dz = h / (resolution.height() - 1);
42 const float du = 1.0 / (resolution.width() - 1);
43 const float dv = 1.0 / (resolution.height() - 1);
44
45 // Iterate over z
46 for (int j = 0; j < resolution.height(); ++j) {
47 const float z = z0 + static_cast<float>(j) * dz;
48 const float v = static_cast<float>(j) * dv;
49
50 // Iterate over x
51 for (int i = 0; i < resolution.width(); ++i) {
52 const float x = x0 + static_cast<float>(i) * dx;
53 const float u = static_cast<float>(i) * du;
54
55 // position
56 *fptr++ = x;
57 *fptr++ = 0.0;
58 *fptr++ = z;
59
60 // texture coordinates
61 *fptr++ = u;
62 *fptr++ = mirrored ? 1.0f - v : v;
63
64 // normal
65 *fptr++ = 0.0f;
66 *fptr++ = 1.0f;
67 *fptr++ = 0.0f;
68
69 // tangent
70 *fptr++ = 1.0f;
71 *fptr++ = 0.0f;
72 *fptr++ = 0.0f;
73 *fptr++ = 1.0f;
74 }
75 }
76
77 return bufferBytes;
78}
79
80QByteArray createPlaneIndexData(const QSize &resolution)
81{
82 // Create the index data. 2 triangles per rectangular face
83 const int faces = 2 * (resolution.width() - 1) * (resolution.height() - 1);
84 const qsizetype indices = 3 * faces;
85 Q_ASSERT(indices < std::numeric_limits<quint16>::max());
86 QByteArray indexBytes;
87 indexBytes.resize(size: indices * sizeof(quint16));
88 quint16* indexPtr = reinterpret_cast<quint16*>(indexBytes.data());
89
90 // Iterate over z
91 for (int j = 0; j < resolution.height() - 1; ++j) {
92 const int rowStartIndex = j * resolution.width();
93 const int nextRowStartIndex = (j + 1) * resolution.width();
94
95 // Iterate over x
96 for (int i = 0; i < resolution.width() - 1; ++i) {
97 // Split quad into two triangles
98 *indexPtr++ = rowStartIndex + i;
99 *indexPtr++ = nextRowStartIndex + i;
100 *indexPtr++ = rowStartIndex + i + 1;
101
102 *indexPtr++ = nextRowStartIndex + i;
103 *indexPtr++ = nextRowStartIndex + i + 1;
104 *indexPtr++ = rowStartIndex + i + 1;
105 }
106 }
107
108 return indexBytes;
109}
110
111} // anonymous
112
113/*!
114 * \qmltype PlaneGeometry
115 * \nativetype Qt3DExtras::QPlaneGeometry
116 * \inqmlmodule Qt3D.Extras
117 * \brief PlaneGeometry allows creation of a plane in 3D space.
118 *
119 * The PlaneGeometry type is most commonly used internally by the PlaneMesh type
120 * but can also be used in custom GeometryRenderer types.
121 */
122
123/*!
124 * \qmlproperty real PlaneGeometry::width
125 *
126 * Holds the plane width.
127 */
128
129/*!
130 * \qmlproperty real PlaneGeometry::height
131 *
132 * Holds the plane height.
133 */
134
135/*!
136 * \qmlproperty size PlaneGeometry::resolution
137 *
138 * Holds the plane resolution.
139 */
140
141/*!
142 * \qmlproperty bool PlaneGeometry::mirrored
143 * \since 5.9
144 *
145 * Controls if the UV coordinates of the plane should be flipped vertically.
146 */
147
148/*!
149 * \qmlproperty Attribute PlaneGeometry::positionAttribute
150 *
151 * Holds the geometry position attribute.
152 */
153
154/*!
155 * \qmlproperty Attribute PlaneGeometry::normalAttribute
156 *
157 * Holds the geometry normal attribute.
158 */
159
160/*!
161 * \qmlproperty Attribute PlaneGeometry::texCoordAttribute
162 *
163 * Holds the geometry texture coordinate attribute.
164 */
165
166/*!
167 * \qmlproperty Attribute PlaneGeometry::tangentAttribute
168 *
169 * Holds the geometry tangent attribute.
170 */
171
172/*!
173 * \qmlproperty Attribute PlaneGeometry::indexAttribute
174 *
175 * Holds the geometry index attribute.
176 */
177
178/*!
179 * \class Qt3DExtras::QPlaneGeometry
180 * \ingroup qt3d-extras-geometries
181 * \inheaderfile Qt3DExtras/QPlaneGeometry
182 * \inmodule Qt3DExtras
183 * \brief The QPlaneGeometry class allows creation of a plane in 3D space.
184 * \since 5.7
185 * \ingroup geometries
186 *
187 * The QPlaneGeometry class is most commonly used internally by the QPlaneMesh
188 * but can also be used in custom Qt3DRender::QGeometryRenderer subclasses.
189 */
190
191/*!
192 * \fn Qt3DExtras::QPlaneGeometry::QPlaneGeometry(QNode *parent)
193 *
194 * Constructs a new QPlaneGeometry with \a parent.
195 */
196QPlaneGeometry::QPlaneGeometry(QPlaneGeometry::QNode *parent)
197 : QGeometry(*new QPlaneGeometryPrivate(), parent)
198{
199 Q_D(QPlaneGeometry);
200 d->init();
201}
202
203/*!
204 * \internal
205 */
206QPlaneGeometry::QPlaneGeometry(QPlaneGeometryPrivate &dd, QNode *parent)
207 : QGeometry(dd, parent)
208{
209 Q_D(QPlaneGeometry);
210 d->init();
211}
212
213/*!
214 * \internal
215 */
216QPlaneGeometry::~QPlaneGeometry()
217{
218}
219
220/*!
221 * Updates vertices based on mesh resolution, width, and height properties.
222 */
223void QPlaneGeometry::updateVertices()
224{
225 Q_D(QPlaneGeometry);
226 const int nVerts = d->m_meshResolution.width() * d->m_meshResolution.height();
227
228 d->m_positionAttribute->setCount(nVerts);
229 d->m_normalAttribute->setCount(nVerts);
230 d->m_texCoordAttribute->setCount(nVerts);
231 d->m_tangentAttribute->setCount(nVerts);
232 d->m_vertexBuffer->setData(d->generateVertexData());
233}
234
235/*!
236 * Updates indices based on mesh resolution.
237 */
238void QPlaneGeometry::updateIndices()
239{
240 Q_D(QPlaneGeometry);
241 const int faces = 2 * (d->m_meshResolution.width() - 1) * (d->m_meshResolution.height() - 1);
242 // Each primitive has 3 vertices
243 d->m_indexAttribute->setCount(faces * 3);
244 d->m_indexBuffer->setData(d->generateIndexData());
245
246}
247
248void QPlaneGeometry::setResolution(const QSize &resolution)
249{
250 Q_D(QPlaneGeometry);
251 if (d->m_meshResolution == resolution)
252 return;
253 d->m_meshResolution = resolution;
254 updateVertices();
255 updateIndices();
256 emit resolutionChanged(resolution);
257}
258
259void QPlaneGeometry::setWidth(float width)
260{
261 Q_D(QPlaneGeometry);
262 if (width == d->m_width)
263 return;
264 d->m_width = width;
265 updateVertices();
266 emit widthChanged(width);
267}
268
269void QPlaneGeometry::setHeight(float height)
270{
271 Q_D(QPlaneGeometry);
272 if (height == d->m_height)
273 return;
274 d->m_height = height;
275 updateVertices();
276 emit heightChanged(height);
277}
278
279void QPlaneGeometry::setMirrored(bool mirrored)
280{
281 Q_D(QPlaneGeometry);
282 if (mirrored == d->m_mirrored)
283 return;
284 d->m_mirrored = mirrored;
285 updateVertices();
286 emit mirroredChanged(mirrored);
287}
288
289/*!
290 * \property Qt3DExtras::QPlaneGeometry::resolution
291 *
292 * Holds the plane resolution.
293 */
294QSize QPlaneGeometry::resolution() const
295{
296 Q_D(const QPlaneGeometry);
297 return d->m_meshResolution;
298}
299
300/*!
301 * \property Qt3DExtras::QPlaneGeometry::width
302 *
303 * Holds the plane width.
304 */
305float QPlaneGeometry::width() const
306{
307 Q_D(const QPlaneGeometry);
308 return d->m_width;
309}
310
311/*!
312 * \property Qt3DExtras::QPlaneGeometry::height
313 *
314 * Holds the plane height.
315 */
316float QPlaneGeometry::height() const
317{
318 Q_D(const QPlaneGeometry);
319 return d->m_height;
320}
321
322/*!
323 * \property Qt3DExtras::QPlaneGeometry::mirrored
324 * \since 5.9
325 *
326 * Controls if the UV coordinates of the plane should be flipped vertically.
327 */
328bool QPlaneGeometry::mirrored() const
329{
330 Q_D(const QPlaneGeometry);
331 return d->m_mirrored;
332}
333
334/*!
335 * \property Qt3DExtras::QPlaneGeometry::positionAttribute
336 *
337 * Holds the geometry position attribute.
338 */
339QAttribute *QPlaneGeometry::positionAttribute() const
340{
341 Q_D(const QPlaneGeometry);
342 return d->m_positionAttribute;
343}
344
345/*!
346 * \property Qt3DExtras::QPlaneGeometry::normalAttribute
347 *
348 * Holds the geometry normal attribute.
349 */
350QAttribute *QPlaneGeometry::normalAttribute() const
351{
352 Q_D(const QPlaneGeometry);
353 return d->m_normalAttribute;
354}
355
356/*!
357 * \property Qt3DExtras::QPlaneGeometry::texCoordAttribute
358 *
359 * Holds the geometry texture coordinate attribute.
360 */
361QAttribute *QPlaneGeometry::texCoordAttribute() const
362{
363 Q_D(const QPlaneGeometry);
364 return d->m_texCoordAttribute;
365}
366
367/*!
368 * \property Qt3DExtras::QPlaneGeometry::tangentAttribute
369 *
370 * Holds the geometry tangent attribute.
371 */
372QAttribute *QPlaneGeometry::tangentAttribute() const
373{
374 Q_D(const QPlaneGeometry);
375 return d->m_tangentAttribute;
376}
377
378/*!
379 * \property Qt3DExtras::QPlaneGeometry::indexAttribute
380 *
381 * Holds the geometry index attribute.
382 */
383QAttribute *QPlaneGeometry::indexAttribute() const
384{
385 Q_D(const QPlaneGeometry);
386 return d->m_indexAttribute;
387}
388
389QPlaneGeometryPrivate::QPlaneGeometryPrivate()
390 : QGeometryPrivate()
391 , m_width(1.0f)
392 , m_height(1.0f)
393 , m_meshResolution(QSize(2, 2))
394 , m_mirrored(false)
395 , m_positionAttribute(nullptr)
396 , m_normalAttribute(nullptr)
397 , m_texCoordAttribute(nullptr)
398 , m_tangentAttribute(nullptr)
399 , m_indexAttribute(nullptr)
400 , m_vertexBuffer(nullptr)
401 , m_indexBuffer(nullptr)
402{
403}
404
405void QPlaneGeometryPrivate::init()
406{
407 Q_Q(QPlaneGeometry);
408 m_positionAttribute = new QAttribute(q);
409 m_normalAttribute = new QAttribute(q);
410 m_texCoordAttribute = new QAttribute(q);
411 m_tangentAttribute = new QAttribute(q);
412 m_indexAttribute = new QAttribute(q);
413 m_vertexBuffer = new Qt3DCore::QBuffer(q);
414 m_indexBuffer = new Qt3DCore::QBuffer(q);
415
416 const int nVerts = m_meshResolution.width() * m_meshResolution.height();
417 const int stride = (3 + 2 + 3 + 4) * sizeof(float);
418 const int faces = 2 * (m_meshResolution.width() - 1) * (m_meshResolution.height() - 1);
419
420 m_positionAttribute->setName(QAttribute::defaultPositionAttributeName());
421 m_positionAttribute->setVertexBaseType(QAttribute::Float);
422 m_positionAttribute->setVertexSize(3);
423 m_positionAttribute->setAttributeType(QAttribute::VertexAttribute);
424 m_positionAttribute->setBuffer(m_vertexBuffer);
425 m_positionAttribute->setByteStride(stride);
426 m_positionAttribute->setCount(nVerts);
427
428 m_texCoordAttribute->setName(QAttribute::defaultTextureCoordinateAttributeName());
429 m_texCoordAttribute->setVertexBaseType(QAttribute::Float);
430 m_texCoordAttribute->setVertexSize(2);
431 m_texCoordAttribute->setAttributeType(QAttribute::VertexAttribute);
432 m_texCoordAttribute->setBuffer(m_vertexBuffer);
433 m_texCoordAttribute->setByteStride(stride);
434 m_texCoordAttribute->setByteOffset(3 * sizeof(float));
435 m_texCoordAttribute->setCount(nVerts);
436
437 m_normalAttribute->setName(QAttribute::defaultNormalAttributeName());
438 m_normalAttribute->setVertexBaseType(QAttribute::Float);
439 m_normalAttribute->setVertexSize(3);
440 m_normalAttribute->setAttributeType(QAttribute::VertexAttribute);
441 m_normalAttribute->setBuffer(m_vertexBuffer);
442 m_normalAttribute->setByteStride(stride);
443 m_normalAttribute->setByteOffset(5 * sizeof(float));
444 m_normalAttribute->setCount(nVerts);
445
446 m_tangentAttribute->setName(QAttribute::defaultTangentAttributeName());
447 m_tangentAttribute->setVertexBaseType(QAttribute::Float);
448 m_tangentAttribute->setVertexSize(4);
449 m_tangentAttribute->setAttributeType(QAttribute::VertexAttribute);
450 m_tangentAttribute->setBuffer(m_vertexBuffer);
451 m_tangentAttribute->setByteStride(stride);
452 m_tangentAttribute->setByteOffset(8 * sizeof(float));
453 m_tangentAttribute->setCount(nVerts);
454
455 m_indexAttribute->setAttributeType(QAttribute::IndexAttribute);
456 m_indexAttribute->setVertexBaseType(QAttribute::UnsignedShort);
457 m_indexAttribute->setBuffer(m_indexBuffer);
458
459 // Each primitive has 3 vertives
460 m_indexAttribute->setCount(faces * 3);
461
462 m_vertexBuffer->setData(generateVertexData());
463 m_indexBuffer->setData(generateIndexData());
464
465 q->addAttribute(attribute: m_positionAttribute);
466 q->addAttribute(attribute: m_texCoordAttribute);
467 q->addAttribute(attribute: m_normalAttribute);
468 q->addAttribute(attribute: m_tangentAttribute);
469 q->addAttribute(attribute: m_indexAttribute);
470}
471
472QByteArray QPlaneGeometryPrivate::generateVertexData() const
473{
474 return createPlaneVertexData(w: m_width, h: m_height, resolution: m_meshResolution, mirrored: m_mirrored);
475}
476
477QByteArray QPlaneGeometryPrivate::generateIndexData() const
478{
479 return createPlaneIndexData(resolution: m_meshResolution);
480}
481
482} // Qt3DExtras
483
484QT_END_NAMESPACE
485
486#include "moc_qplanegeometry.cpp"
487

source code of qt3d/src/extras/geometries/qplanegeometry.cpp