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

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