diff options
Diffstat (limited to 'src/threed/math3d/qtriangle3d.cpp')
| -rw-r--r-- | src/threed/math3d/qtriangle3d.cpp | 379 |
1 files changed, 0 insertions, 379 deletions
diff --git a/src/threed/math3d/qtriangle3d.cpp b/src/threed/math3d/qtriangle3d.cpp deleted file mode 100644 index ac1f0898..00000000 --- a/src/threed/math3d/qtriangle3d.cpp +++ /dev/null @@ -1,379 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). -** All rights reserved. -** Contact: Nokia Corporation ([email protected]) -** -** This file is part of the QtQuick3D module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** GNU Lesser General Public License Usage -** 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. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU General -** Public License version 3.0 as published by the Free Software Foundation -** and appearing in the file LICENSE.GPL included in the packaging of this -** file. Please review the following information to ensure the GNU General -** Public License version 3.0 requirements will be met: -** http://www.gnu.org/copyleft/gpl.html. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms and -** conditions contained in a signed written agreement between you and Nokia. -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -#include "qtriangle3d.h" -#include <QtGui/qmatrix4x4.h> -#include <QtCore/qnumeric.h> - -QT_BEGIN_NAMESPACE - -/*! - \class QTriangle3D - \brief The QTriangle3D class represents a triangle as three points in 3D space. - \since 4.8 - \ingroup qt3d - \ingroup qt3d::math - - A triangle is defined by 3 points in 3D space. Since any 3 points define - a plane, the triangle can be thought of as defining a plane, and forming a - geometric region in that plane. - - If you need a simple plane, with no particular geometry, then - QPlane3D is a more compact and mathematically sufficient class. - - The three points are labelled p(), q() and r() for consistency with - textbook treatments. It is recommended that the points be supplied - in counter-clockwise order for correct orientation of the - triangle's plane(). - - \sa QPlane3D -*/ - -/*! - \fn QTriangle3D::QTriangle3D() - - Constructs a default triangle which lies in the x-z plane, - with the three vertices (0, 0, 0), (1, 0, 0), and (0, 1, 0). -*/ - -/*! - \fn QTriangle3D::QTriangle3D(const QVector3D &p, const QVector3D &q, const QVector3D &r) - - Constructs a triangle with the supplied \a p, \a q and \a r vertices. -*/ - -/*! - \fn QVector3D QTriangle3D::p() const - - Returns the value of the P vertex on the triangle. - - \sa q(), r(), setP() -*/ - -/*! - \fn void QTriangle3D::setP(const QVector3D &point) - - Sets the value of the P vertex on the triangle to \a point. - - \sa setQ(), setR(), p() -*/ - -/*! - \fn QVector3D QTriangle3D::q() const - - Returns the value of the Q vertex on the triangle. - - \sa p(), r(), setQ() -*/ - -/*! - \fn void QTriangle3D::setQ(const QVector3D &point) - - Sets the value of the Q vertex on the triangle \a point. - - \sa setP(), setR(), q() -*/ - - -/*! - \fn QVector3D QTriangle3D::r() const - - Returns the value of the R vertex on the triangle. - - \sa p(), q(), setR() -*/ - -/*! - \fn void QTriangle3D::setR(const QVector3D &point) - - Sets the value of the R vertex on the triangle \a point. - - \sa setP(), setQ(), r() -*/ - -/*! - \fn QPlane3D QTriangle3D::plane() const - - Returns the plane in which the triangle lies. - - \sa QPlane3D -*/ - -/*! - \fn QVector3D QTriangle3D::center() const - - Returns the center of the triangle, which is the geometric average of the - three vertices. -*/ - -/*! - \fn QVector3D QTriangle3D::faceNormal() const - - Returns the vector normal to this triangle, computed from the - cross-product of P-Q and Q-R. The result is not normalized. -*/ - -/*! - Returns true if this triangle contains \a point; false otherwise. - To contain the \a point means that: - \list - \o the point lies on the same plane as the triangle, and - \o the point - \list - \o lies either wholly within the triangle, or - \o lies on one of the sides, or - \o coincides with one of the 3 vertices - \endlist - \endlist - - \sa intersects() -*/ -bool QTriangle3D::contains(const QVector3D &point) const -{ - // Check if the point is on the triangle's plane first. - QVector3D normal = QVector3D::crossProduct(m_q - m_p, m_r - m_q); - if (!qFuzzyIsNull(float(QVector3D::dotProduct(normal, m_p - point)))) - return false; - - // Compute the barycentric co-ordinates and use them to determine - // if the point is within the triangle. - QVector2D c = uv(point); - if (c.x() < 0.0f || c.x() > 1.0f) - return false; - if (c.y() < 0.0f || c.y() > 1.0f) - return false; - if ((c.x() + c.y()) > 1.0f) - return false; - return true; -} - -/*! - Returns true if the \a ray intersects this triangle; false otherwise. - - This function will return false if the triangle is degenerate. - - \sa contains(), intersection() -*/ -bool QTriangle3D::intersects(const QRay3D &ray) const -{ - qreal t = plane().intersection(ray); - if (qIsNaN(t)) - return false; - return contains(ray.point(t)); -} - -/*! - Returns the t value at which \a ray intersects this triangle, or - not-a-number if there is no intersection. - - When the \a ray intersects this triangle, the return value is a - parametric value that can be passed to QRay3D::point() to determine - the actual intersection point, as shown in the following example: - - \code - qreal t = triangle.intersection(ray); - QVector3D pt; - if (qIsNaN(t)) { - qWarning("no intersection occurred"); - else - pt = ray.point(t); - \endcode - - \sa intersects(), contains(), QRay3D::point() - */ -qreal QTriangle3D::intersection(const QRay3D &ray) const -{ - qreal t = plane().intersection(ray); - if (qIsNaN(t) || contains(ray.point(t))) - return t; - return qSNaN(); -} - -/*! - Transforms the points of this triangle according to \a matrix. - - \sa transformed() -*/ -void QTriangle3D::transform(const QMatrix4x4 &matrix) -{ - m_p = matrix * m_p; - m_q = matrix * m_q; - m_r = matrix * m_r; -} - -/*! - Returns a new triangle that results from transforming this - one using \a matrix. - - \sa transform() -*/ -QTriangle3D QTriangle3D::transformed(const QMatrix4x4 &matrix) const -{ - return QTriangle3D(matrix * m_p, matrix * m_q, matrix * m_r); -} - -/*! - Returns the (u, v) barycentric co-ordinates of \a point within - this triangle. - - The returned barycentric co-ordinates will be (1, 0) at p(), - (0, 1) at q(), and (0, 0) at r(). Technically, barycentric - co-ordinates have three components with the corners at - (1, 0, 0), (0, 1, 0), and (0, 0, 1). However, the third - component is always equal to (1 - u - v) so we do not return it. - - The typical use case for this function is to convert an intersection - point on a triangle into the texture co-ordinate corresponding to - that point. If \c p, \c q, and \c r are the points on the triangle, - with corresponding texture co-ordinates \c tp, \c tq, and \c tr, - then the texture co-ordinate \c tc of \a point can be determined - by the following code: - - \code - QTriangle3D triangle(p, q, r); - QVector2D uv = triangle.uv(point); - QVector2D tc = uv.x() * tp + uv.y() * tq + (1 - uv.x() - uv.y()) * tr; - \endcode - - \sa contains(), intersection() -*/ -QVector2D QTriangle3D::uv(const QVector3D &point) const -{ - // Algorithm from: http://www.blackpawn.com/texts/pointinpoly/default.html - // More: http://en.wikipedia.org/wiki/Barycentric_coordinates_(mathematics) - QVector3D rq = m_q - m_r; - QVector3D rp = m_p - m_r; - QVector3D pp = point - m_r; - qreal dot_rq_rq = QVector3D::dotProduct(rq, rq); - qreal dot_rq_rp = QVector3D::dotProduct(rq, rp); - qreal dot_rq_pp = QVector3D::dotProduct(rq, pp); - qreal dot_rp_rp = QVector3D::dotProduct(rp, rp); - qreal dot_rp_pp = QVector3D::dotProduct(rp, pp); - qreal det = dot_rq_rq * dot_rp_rp - dot_rq_rp * dot_rq_rp; - if (qFuzzyIsNull(float(det))) { - // The point is probably not in the triangle, or the triangle - // is degenerate. Return an out of range value for (u, v) so - // that contains() will fail when this case happens. - return QVector2D(-1.0f, -1.0f); - } - return QVector2D((dot_rq_rq * dot_rp_pp - dot_rq_rp * dot_rq_pp) / det, - (dot_rp_rp * dot_rq_pp - dot_rq_rp * dot_rp_pp) / det); -} - -/*! - \fn bool QTriangle3D::operator==(const QTriangle3D &other) - - Returns true if this triangle is the same as \a other; false otherwise. - - \sa operator!=() -*/ - -/*! - \fn bool QTriangle3D::operator!=(const QTriangle3D &other) - - Returns true if this triangle is not the same as \a other; false otherwise. - - \sa operator==() -*/ - -/*! - \fn bool qFuzzyCompare(const QTriangle3D &triangle1, const QTriangle3D &triangle2) - \relates QTriangle3D - - Returns true if \a triangle1 and \a triangle2 are almost equal; - false otherwise. -*/ - -#ifndef QT_NO_DEBUG_STREAM - -QDebug operator<<(QDebug dbg, const QTriangle3D &triangle) -{ - dbg.nospace() << "QTriangle3D((" - << triangle.p().x() << ", " << triangle.p().y() << ", " - << triangle.p().z() << "), (" - << triangle.q().x() << ", " << triangle.q().y() << ", " - << triangle.q().z() << "), (" - << triangle.r().x() << ", " << triangle.r().y() << ", " - << triangle.r().z() << "))"; - return dbg.space(); -} - -#endif - -#ifndef QT_NO_DATASTREAM - -/*! - \fn QDataStream &operator<<(QDataStream &stream, const QTriangle3D &triangle) - \relates QTriangle3D - - Writes the given \a triangle to the given \a stream and returns a - reference to the stream. -*/ - -QDataStream &operator<<(QDataStream &stream, const QTriangle3D &triangle) -{ - stream << triangle.p(); - stream << triangle.q(); - stream << triangle.r(); - return stream; -} - -/*! - \fn QDataStream &operator>>(QDataStream &stream, QTriangle3D &triangle) - \relates QTriangle3D - - Reads a 3D triangle from the given \a stream into the given \a triangle - and returns a reference to the stream. -*/ - -QDataStream &operator>>(QDataStream &stream, QTriangle3D &triangle) -{ - QVector3D p, q, r; - stream >> p; - stream >> q; - stream >> r; - triangle = QTriangle3D(p, q, r); - return stream; -} - -#endif // QT_NO_DATASTREAM - -QT_END_NAMESPACE |