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// Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qextrudedtextgeometry.h"
#include "qextrudedtextgeometry_p.h"
#include <Qt3DCore/qbuffer.h>
#include <Qt3DCore/qattribute.h>
#include <private/qtriangulator_p.h>
#include <qmath.h>
#include <QVector3D>
#include <QTextLayout>
#include <QTime>
#include <QPainterPath>
QT_BEGIN_NAMESPACE
namespace Qt3DExtras {
namespace {
static float edgeSplitAngle = 90.f * 0.1f;
using IndexType = unsigned int;
struct TriangulationData {
struct Outline {
int begin;
int end;
};
std::vector<QVector3D> vertices;
std::vector<IndexType> indices;
std::vector<Outline> outlines;
std::vector<IndexType> outlineIndices;
bool inverted;
};
TriangulationData triangulate(const QString &text, const QFont &font)
{
TriangulationData result;
int beginOutline = 0;
// Initialize path with text and extract polygons
QPainterPath path;
path.setFillRule(Qt::WindingFill);
path.addText(0, 0, font, text);
QList<QPolygonF> polygons = path.toSubpathPolygons(QTransform().scale(1., -1.));
// maybe glyph has no geometry
if (polygons.empty())
return result;
const size_t prevNumIndices = result.indices.size();
// Reset path and add previously extracted polygons (which where spatially transformed)
path = QPainterPath();
path.setFillRule(Qt::WindingFill);
for (QPolygonF &p : polygons)
path.addPolygon(p);
// Extract polylines out of the path, this allows us to retrieve indices for each glyph outline
QPolylineSet polylines = qPolyline(path);
std::vector<IndexType> tmpIndices;
tmpIndices.resize(size_t(polylines.indices.size()));
memcpy(tmpIndices.data(), polylines.indices.data(), size_t(polylines.indices.size()) * sizeof(IndexType));
int lastIndex = 0;
for (const IndexType idx : tmpIndices) {
if (idx == std::numeric_limits<IndexType>::max()) {
const int endOutline = lastIndex;
result.outlines.push_back({beginOutline, endOutline});
beginOutline = endOutline;
} else {
result.outlineIndices.push_back(idx);
++lastIndex;
}
}
// Triangulate path
const QTriangleSet triangles = qTriangulate(path);
// Append new indices to result.indices buffer
result.indices.resize(result.indices.size() + size_t(triangles.indices.size()));
memcpy(&result.indices[prevNumIndices], triangles.indices.data(), size_t(triangles.indices.size()) * sizeof(IndexType));
for (size_t i = prevNumIndices, m = result.indices.size(); i < m; ++i)
result.indices[i] += IndexType(result.vertices.size());
// Append new triangles to result.vertices
result.vertices.reserve(size_t(triangles.vertices.size()) / 2);
for (qsizetype i = 0, m = triangles.vertices.size(); i < m; i += 2)
result.vertices.push_back(QVector3D(triangles.vertices[i] / font.pointSizeF(), triangles.vertices[i + 1] / font.pointSizeF(), 0.0f));
return result;
}
inline QVector3D mix(const QVector3D &a, const QVector3D &b, float ratio)
{
return a + (b - a) * ratio;
}
} // anonymous namespace
QExtrudedTextGeometryPrivate::QExtrudedTextGeometryPrivate()
: QGeometryPrivate()
, m_font(QFont(QStringLiteral("Arial")))
, m_depth(1.f)
, m_positionAttribute(nullptr)
, m_normalAttribute(nullptr)
, m_indexAttribute(nullptr)
, m_vertexBuffer(nullptr)
, m_indexBuffer(nullptr)
{
m_font.setPointSize(4);
}
void QExtrudedTextGeometryPrivate::init()
{
Q_Q(QExtrudedTextGeometry);
m_positionAttribute = new Qt3DCore::QAttribute(q);
m_normalAttribute = new Qt3DCore::QAttribute(q);
m_indexAttribute = new Qt3DCore::QAttribute(q);
m_vertexBuffer = new Qt3DCore::QBuffer(q);
m_indexBuffer = new Qt3DCore::QBuffer(q);
const quint32 elementSize = 3 + 3;
const quint32 stride = elementSize * sizeof(float);
m_positionAttribute->setName(Qt3DCore::QAttribute::defaultPositionAttributeName());
m_positionAttribute->setVertexBaseType(Qt3DCore::QAttribute::Float);
m_positionAttribute->setVertexSize(3);
m_positionAttribute->setAttributeType(Qt3DCore::QAttribute::VertexAttribute);
m_positionAttribute->setBuffer(m_vertexBuffer);
m_positionAttribute->setByteStride(stride);
m_positionAttribute->setByteOffset(0);
m_positionAttribute->setCount(0);
m_normalAttribute->setName(Qt3DCore::QAttribute::defaultNormalAttributeName());
m_normalAttribute->setVertexBaseType(Qt3DCore::QAttribute::Float);
m_normalAttribute->setVertexSize(3);
m_normalAttribute->setAttributeType(Qt3DCore::QAttribute::VertexAttribute);
m_normalAttribute->setBuffer(m_vertexBuffer);
m_normalAttribute->setByteStride(stride);
m_normalAttribute->setByteOffset(3 * sizeof(float));
m_normalAttribute->setCount(0);
m_indexAttribute->setAttributeType(Qt3DCore::QAttribute::IndexAttribute);
m_indexAttribute->setVertexBaseType(Qt3DCore::QAttribute::UnsignedInt);
m_indexAttribute->setBuffer(m_indexBuffer);
m_indexAttribute->setCount(0);
q->addAttribute(m_positionAttribute);
q->addAttribute(m_normalAttribute);
q->addAttribute(m_indexAttribute);
update();
}
/*!
* \qmltype ExtrudedTextGeometry
* \nativetype Qt3DExtras::QExtrudedTextGeometry
* \inqmlmodule Qt3D.Extras
* \brief ExtrudedTextGeometry allows creation of a 3D text in 3D space.
*
* The ExtrudedTextGeometry type is most commonly used internally by the
* ExtrudedTextMesh type but can also be used in custom GeometryRenderer types.
*
* The origin of the geometry is the rear left end of the text's baseline.
*/
/*!
* \qmlproperty string ExtrudedTextGeometry::text
*
* Holds the text used for the mesh.
*/
/*!
* \qmlproperty font ExtrudedTextGeometry::font
*
* Holds the font of the text.
*
* The geometry is normalized by the font's pointSize, so a larger pointSize
* will result in smoother, rather than larger, text. pixelSize should not
* be used.
*/
/*!
* \qmlproperty real ExtrudedTextGeometry::depth
*
* Holds the extrusion depth of the text.
*/
/*!
* \qmlproperty Attribute ExtrudedTextGeometry::positionAttribute
*
* Holds the geometry position attribute.
*/
/*!
* \qmlproperty Attribute ExtrudedTextGeometry::normalAttribute
*
* Holds the geometry normal attribute.
*/
/*!
* \qmlproperty Attribute ExtrudedTextGeometry::indexAttribute
*
* Holds the geometry index attribute.
*/
/*!
* \class Qt3DExtras::QExtrudedTextGeometry
* \inheaderfile Qt3DExtras/QExtrudedTextGeometry
* \inmodule Qt3DExtras
* \brief The QExtrudedTextGeometry class allows creation of a 3D extruded text
* in 3D space.
* \since 5.9
* \ingroup geometries
* \inherits Qt3DCore::QGeometry
*
* The QExtrudedTextGeometry class is most commonly used internally by the QText3DMesh
* but can also be used in custom Qt3DRender::QGeometryRenderer subclasses.
*
* The origin of the geometry is the rear left end of the text's baseline.
*/
/*!
* Constructs a new QExtrudedTextGeometry with \a parent.
*/
QExtrudedTextGeometry::QExtrudedTextGeometry(Qt3DCore::QNode *parent)
: QGeometry(*new QExtrudedTextGeometryPrivate(), parent)
{
Q_D(QExtrudedTextGeometry);
d->init();
}
/*!
* \internal
*/
QExtrudedTextGeometry::QExtrudedTextGeometry(QExtrudedTextGeometryPrivate &dd, Qt3DCore::QNode *parent)
: QGeometry(dd, parent)
{
Q_D(QExtrudedTextGeometry);
d->init();
}
/*!
* \internal
*/
QExtrudedTextGeometry::~QExtrudedTextGeometry()
{}
/*!
* \internal
* Updates vertices based on text, font, extrusionLength and smoothAngle properties.
*/
void QExtrudedTextGeometryPrivate::update()
{
if (m_text.trimmed().isEmpty()) // save enough?
return;
TriangulationData data = triangulate(m_text, m_font);
const IndexType numVertices = IndexType(data.vertices.size());
const size_t numIndices = data.indices.size();
struct Vertex {
QVector3D position;
QVector3D normal;
};
std::vector<IndexType> indices;
std::vector<Vertex> vertices;
// TODO: keep 'vertices.size()' small when extruding
vertices.reserve(data.vertices.size() * 2);
for (QVector3D &v : data.vertices) // front face
vertices.push_back({ v, // vertex
QVector3D(0.0f, 0.0f, -1.0f) }); // normal
for (QVector3D &v : data.vertices) // front face
vertices.push_back({ QVector3D(v.x(), v.y(), m_depth), // vertex
QVector3D(0.0f, 0.0f, 1.0f) }); // normal
int verticesIndex = int(vertices.size());
for (size_t i = 0; i < data.outlines.size(); ++i) {
const int begin = data.outlines[i].begin;
const int end = data.outlines[i].end;
const int verticesIndexBegin = verticesIndex;
if (begin == end)
continue;
QVector3D prevNormal = QVector3D::crossProduct(
vertices[data.outlineIndices[end - 1] + numVertices].position - vertices[data.outlineIndices[end - 1]].position,
vertices[data.outlineIndices[begin]].position - vertices[data.outlineIndices[end - 1]].position).normalized();
for (int j = begin; j < end; ++j) {
const bool isLastIndex = (j == end - 1);
const IndexType cur = data.outlineIndices[j];
const IndexType next = data.outlineIndices[((j - begin + 1) % (end - begin)) + begin]; // normalize, bring in range and adjust
const QVector3D normal = QVector3D::crossProduct(vertices[cur + numVertices].position - vertices[cur].position, vertices[next].position - vertices[cur].position).normalized();
// use smooth normals in case of a short angle
const bool smooth = QVector3D::dotProduct(prevNormal, normal) > (90.0f - edgeSplitAngle) / 90.0f;
const QVector3D resultNormal = smooth ? mix(prevNormal, normal, 0.5f) : normal;
if (!smooth) {
vertices.push_back({vertices[cur].position, prevNormal});
vertices.push_back({vertices[cur + numVertices].position, prevNormal});
verticesIndex += 2;
}
vertices.push_back({vertices[cur].position, resultNormal});
vertices.push_back({vertices[cur + numVertices].position, resultNormal});
const int v0 = verticesIndex;
const int v1 = verticesIndex + 1;
const int v2 = isLastIndex ? verticesIndexBegin : verticesIndex + 2;
const int v3 = isLastIndex ? verticesIndexBegin + 1 : verticesIndex + 3;
indices.push_back(v0);
indices.push_back(v1);
indices.push_back(v2);
indices.push_back(v2);
indices.push_back(v1);
indices.push_back(v3);
verticesIndex += 2;
prevNormal = normal;
}
}
{ // upload vertices
QByteArray data;
data.resize(vertices.size() * sizeof(Vertex));
memcpy(data.data(), vertices.data(), vertices.size() * sizeof(Vertex));
m_vertexBuffer->setData(data);
m_positionAttribute->setCount(int(vertices.size()));
m_normalAttribute->setCount(int(vertices.size()));
}
// resize for following insertions
const int indicesOffset = int(indices.size());
indices.resize(indices.size() + numIndices * 2);
// copy values for back faces
IndexType *indicesFaces = indices.data() + indicesOffset;
memcpy(indicesFaces, data.indices.data(), numIndices * sizeof(IndexType));
// insert values for front face and flip triangles
for (size_t j = 0; j < numIndices; j += 3) {
indicesFaces[numIndices + j ] = indicesFaces[j ] + numVertices;
indicesFaces[numIndices + j + 1] = indicesFaces[j + 2] + numVertices;
indicesFaces[numIndices + j + 2] = indicesFaces[j + 1] + numVertices;
}
{ // upload indices
QByteArray data;
data.resize(indices.size() * sizeof(IndexType));
memcpy(data.data(), indices.data(), indices.size() * sizeof(IndexType));
m_indexBuffer->setData(data);
m_indexAttribute->setCount(uint(indices.size()));
}
}
void QExtrudedTextGeometry::setText(const QString &text)
{
Q_D(QExtrudedTextGeometry);
if (d->m_text != text) {
d->m_text = text;
d->update();
emit textChanged(text);
}
}
void QExtrudedTextGeometry::setFont(const QFont &font)
{
Q_D(QExtrudedTextGeometry);
if (d->m_font != font) {
d->m_font = font;
d->update();
emit fontChanged(font);
}
}
void QExtrudedTextGeometry::setDepth(float depth)
{
Q_D(QExtrudedTextGeometry);
if (d->m_depth != depth) {
d->m_depth = depth;
d->update();
emit depthChanged(depth);
}
}
/*!
* \property Qt3DExtras::QExtrudedTextGeometry::text
*
* Holds the text used for the mesh.
*/
QString QExtrudedTextGeometry::text() const
{
Q_D(const QExtrudedTextGeometry);
return d->m_text;
}
/*!
* \property Qt3DExtras::QExtrudedTextGeometry::font
*
* Holds the font of the text.
*
* The geometry is normalized by the font's pointSize, so a larger pointSize
* will result in smoother, rather than larger, text. pixelSize should not
* be used.
*/
QFont QExtrudedTextGeometry::font() const
{
Q_D(const QExtrudedTextGeometry);
return d->m_font;
}
/*!
* \property Qt3DExtras::QExtrudedTextGeometry::extrusionLength
*
* Holds the extrusion length of the text.
*/
float QExtrudedTextGeometry::extrusionLength() const
{
Q_D(const QExtrudedTextGeometry);
return d->m_depth;
}
/*!
* \property Qt3DExtras::QExtrudedTextGeometry::positionAttribute
*
* Holds the geometry position attribute.
*/
Qt3DCore::QAttribute *QExtrudedTextGeometry::positionAttribute() const
{
Q_D(const QExtrudedTextGeometry);
return d->m_positionAttribute;
}
/*!
* \property Qt3DExtras::QExtrudedTextGeometry::normalAttribute
*
* Holds the geometry normal attribute.
*/
Qt3DCore::QAttribute *QExtrudedTextGeometry::normalAttribute() const
{
Q_D(const QExtrudedTextGeometry);
return d->m_normalAttribute;
}
/*!
* \property Qt3DExtras::QExtrudedTextGeometry::indexAttribute
*
* Holds the geometry index attribute.
*/
Qt3DCore::QAttribute *QExtrudedTextGeometry::indexAttribute() const
{
Q_D(const QExtrudedTextGeometry);
return d->m_indexAttribute;
}
} // Qt3DExtras
QT_END_NAMESPACE
#include "moc_qextrudedtextgeometry.cpp"