QPlaneGeometry refactored into a public class

Change-Id: I16e2a3a70f7f70c6ad42034a4d57bf2b6031400c
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

1 files changed, 378 insertions, 0 deletions

diff --git a/src/render/geometry/qplanegeometry.cpp b/src/render/geometry/qplanegeometry.cpp
new file mode 100644
index 000000000..58b87797b
--- /dev/null
+++ b/src/render/geometry/qplanegeometry.cpp
@@ -0,0 +1,378 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://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.LGPLv3 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.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 later 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 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qplanegeometry.h"
+#include "qplanegeometry_p.h"
+#include <Qt3DRenderer/qattribute.h>
+#include <Qt3DRenderer/qbuffer.h>
+#include <Qt3DRenderer/qbufferfunctor.h>
+#include <limits>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3DRender {
+
+namespace {
+
+QByteArray createPlaneVertexData(float w, float h, const QSize &resolution)
+{
+    Q_ASSERT(w > 0.0f);
+    Q_ASSERT(h > 0.0f);
+    Q_ASSERT(resolution.width() >= 2);
+    Q_ASSERT(resolution.height() >= 2);
+
+    const int nVerts = resolution.width() * resolution.height();
+
+    // Populate a buffer with the interleaved per-vertex data with
+    // vec3 pos, vec2 texCoord, vec3 normal, vec4 tangent
+    const quint32 elementSize = 3 + 2 + 3 + 4;
+    const quint32 stride = elementSize * sizeof(float);
+    QByteArray bufferBytes;
+    bufferBytes.resize(stride * nVerts);
+    float* fptr = reinterpret_cast<float*>(bufferBytes.data());
+
+    const float x0 = -w / 2.0f;
+    const float z0 = -h / 2.0f;
+    const float dx = w / (resolution.width() - 1);
+    const float dz = h / (resolution.height() - 1);
+    const float du = 1.0 / (resolution.width() - 1);
+    const float dv = 1.0 / (resolution.height() - 1);
+
+    // Iterate over z
+    for (int j = 0; j < resolution.height(); ++j) {
+        const float z = z0 + static_cast<float>(j) * dz;
+        const float v = static_cast<float>(j) * dv;
+
+        // Iterate over x
+        for (int i = 0; i < resolution.width(); ++i) {
+            const float x = x0 + static_cast<float>(i) * dx;
+            const float u = static_cast<float>(i) * du;
+
+            // position
+            *fptr++ = x;
+            *fptr++ = 0.0;
+            *fptr++ = z;
+
+            // texture coordinates
+            *fptr++ = u;
+            *fptr++ = v;
+
+            // normal
+            *fptr++ = 0.0f;
+            *fptr++ = 1.0f;
+            *fptr++ = 0.0f;
+
+            // tangent
+            *fptr++ = 1.0f;
+            *fptr++ = 0.0f;
+            *fptr++ = 0.0f;
+            *fptr++ = 1.0f;
+        }
+    }
+
+    return bufferBytes;
+}
+
+QByteArray createPlaneIndexData(const QSize &resolution)
+{
+    // Create the index data. 2 triangles per rectangular face
+    const int faces = 2 * (resolution.width() - 1) * (resolution.height() - 1);
+    const int indices = 3 * faces;
+    Q_ASSERT(indices < std::numeric_limits<quint16>::max());
+    QByteArray indexBytes;
+    indexBytes.resize(indices * sizeof(quint16));
+    quint16* indexPtr = reinterpret_cast<quint16*>(indexBytes.data());
+
+    // Iterate over z
+    for (int j = 0; j < resolution.height() - 1; ++j) {
+        const int rowStartIndex = j * resolution.width();
+        const int nextRowStartIndex = (j + 1) * resolution.width();
+
+        // Iterate over x
+        for (int i = 0; i < resolution.width() - 1; ++i) {
+            // Split quad into two triangles
+            *indexPtr++ = rowStartIndex + i;
+            *indexPtr++ = nextRowStartIndex + i;
+            *indexPtr++ = rowStartIndex + i + 1;
+
+            *indexPtr++ = nextRowStartIndex + i;
+            *indexPtr++ = nextRowStartIndex + i + 1;
+            *indexPtr++ = rowStartIndex + i + 1;
+        }
+    }
+
+    return indexBytes;
+}
+
+} // anonymous
+
+class PlaneVertexBufferFunctor : public QBufferFunctor
+{
+public:
+    explicit PlaneVertexBufferFunctor(float w, float h, const QSize &resolution)
+        : m_width(w)
+        , m_height(h)
+        , m_resolution(resolution)
+    {}
+
+    ~PlaneVertexBufferFunctor() {}
+
+    QByteArray operator()() Q_DECL_FINAL
+    {
+        return createPlaneVertexData(m_width, m_height, m_resolution);
+    }
+
+    bool operator ==(const QBufferFunctor &other) const Q_DECL_FINAL
+    {
+        const PlaneVertexBufferFunctor *otherFunctor = functor_cast<PlaneVertexBufferFunctor>(&other);
+        if (otherFunctor != Q_NULLPTR)
+            return (otherFunctor->m_width == m_width &&
+                    otherFunctor->m_height == m_height &&
+                    otherFunctor->m_resolution == m_resolution);
+        return false;
+    }
+
+    QT3D_FUNCTOR(PlaneVertexBufferFunctor)
+
+    private:
+        float m_width;
+    float m_height;
+    QSize m_resolution;
+};
+
+class PlaneIndexBufferFunctor : public QBufferFunctor
+{
+public:
+    explicit PlaneIndexBufferFunctor(const QSize &resolution)
+        : m_resolution(resolution)
+    {}
+
+    ~PlaneIndexBufferFunctor() {}
+
+    QByteArray operator()() Q_DECL_FINAL
+    {
+        return createPlaneIndexData(m_resolution);
+    }
+
+    bool operator ==(const QBufferFunctor &other) const Q_DECL_FINAL
+    {
+        const PlaneIndexBufferFunctor *otherFunctor = functor_cast<PlaneIndexBufferFunctor>(&other);
+        if (otherFunctor != Q_NULLPTR)
+            return (otherFunctor->m_resolution == m_resolution);
+        return false;
+    }
+
+    QT3D_FUNCTOR(PlaneIndexBufferFunctor)
+
+    private:
+        QSize m_resolution;
+};
+
+QPlaneGeometry::QPlaneGeometry(QPlaneGeometry::QNode *parent)
+    : QGeometry(*new QPlaneGeometryPrivate(), parent)
+{
+    Q_D(QPlaneGeometry);
+    d->init();
+}
+
+QPlaneGeometry::QPlaneGeometry(QPlaneGeometryPrivate &dd, QNode *parent)
+    : QGeometry(dd, parent)
+{
+    Q_D(QPlaneGeometry);
+    d->init();
+}
+
+QPlaneGeometry::~QPlaneGeometry()
+{
+    QGeometry::cleanup();
+}
+
+void QPlaneGeometry::updateVertices()
+{
+    Q_D(QPlaneGeometry);
+    const int nVerts = d->m_meshResolution.width() * d->m_meshResolution.height();
+
+    d->m_positionAttribute->setCount(nVerts);
+    d->m_normalAttribute->setCount(nVerts);
+    d->m_texCoordAttribute->setCount(nVerts);
+    d->m_tangentAttribute->setCount(nVerts);
+    d->m_vertexBuffer->setBufferFunctor(QBufferFunctorPtr(new PlaneVertexBufferFunctor(d->m_width, d->m_height, d->m_meshResolution)));
+}
+
+void QPlaneGeometry::updateIndices()
+{
+    Q_D(QPlaneGeometry);
+    const int faces = 2 * (d->m_meshResolution.width() - 1) * (d->m_meshResolution.height() - 1);
+    // Each primitive has 3 vertices
+    d->m_indexAttribute->setCount(faces * 3);
+    d->m_indexBuffer->setBufferFunctor(QBufferFunctorPtr(new PlaneIndexBufferFunctor(d->m_meshResolution)));
+
+}
+
+void QPlaneGeometry::setResolution(const QSize &resolution)
+{
+    Q_D(QPlaneGeometry);
+    if (d->m_meshResolution == resolution)
+        return;
+    d->m_meshResolution = resolution;
+    updateVertices();
+    updateIndices();
+    emit resolutionChanged();
+}
+
+void QPlaneGeometry::setWidth(float width)
+{
+    Q_D(QPlaneGeometry);
+    if (width == d->m_width)
+        return;
+    d->m_width = width;
+    updateVertices();
+    emit widthChanged();
+}
+
+void QPlaneGeometry::setHeight(float height)
+{
+    Q_D(QPlaneGeometry);
+    if (height == d->m_height)
+        return;
+    d->m_height = height;
+    updateVertices();
+    emit heightChanged();
+}
+
+QSize QPlaneGeometry::resolution() const
+{
+    Q_D(const QPlaneGeometry);
+    return d->m_meshResolution;
+}
+
+int QPlaneGeometry::width() const
+{
+    Q_D(const QPlaneGeometry);
+    return d->m_width;
+}
+
+int QPlaneGeometry::height() const
+{
+    Q_D(const QPlaneGeometry);
+    return d->m_height;
+}
+
+QPlaneGeometryPrivate::QPlaneGeometryPrivate()
+    : QGeometryPrivate()
+    , m_width(1.0f)
+    , m_height(1.0f)
+    , m_meshResolution(QSize(2, 2))
+    , m_positionAttribute(Q_NULLPTR)
+    , m_normalAttribute(Q_NULLPTR)
+    , m_texCoordAttribute(Q_NULLPTR)
+    , m_tangentAttribute(Q_NULLPTR)
+    , m_indexAttribute(Q_NULLPTR)
+    , m_vertexBuffer(Q_NULLPTR)
+    , m_indexBuffer(Q_NULLPTR)
+{
+}
+
+void QPlaneGeometryPrivate::init()
+{
+    Q_Q(QPlaneGeometry);
+    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 QBuffer(QBuffer::VertexBuffer, q);
+    m_indexBuffer = new QBuffer(QBuffer::IndexBuffer, q);
+
+    const int nVerts = m_meshResolution.width() * m_meshResolution.height();
+    const int stride = (3 + 2 + 3 + 4) * sizeof(float);
+    const int faces = 2 * (m_meshResolution.width() - 1) * (m_meshResolution.height() - 1);
+
+    m_positionAttribute->setName(QAttribute::defaultPositionAttributeName());
+    m_positionAttribute->setDataType(QAttribute::Float);
+    m_positionAttribute->setDataSize(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->setDataType(QAttribute::Float);
+    m_texCoordAttribute->setDataSize(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->setDataType(QAttribute::Float);
+    m_normalAttribute->setDataSize(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->setDataType(QAttribute::Float);
+    m_tangentAttribute->setDataSize(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->setDataType(QAttribute::UnsignedShort);
+    m_indexAttribute->setBuffer(m_indexBuffer);
+
+    // Each primitive has 3 vertives
+    m_indexAttribute->setCount(faces * 3);
+
+    m_vertexBuffer->setBufferFunctor(QBufferFunctorPtr(new PlaneVertexBufferFunctor(m_width, m_height, m_meshResolution)));
+    m_indexBuffer->setBufferFunctor(QBufferFunctorPtr(new PlaneIndexBufferFunctor(m_meshResolution)));
+
+    q->addAttribute(m_positionAttribute);
+    q->addAttribute(m_texCoordAttribute);
+    q->addAttribute(m_normalAttribute);
+    q->addAttribute(m_tangentAttribute);
+    q->addAttribute(m_indexAttribute);
+}
+
+} // Qt3DRender
+
+QT_END_NAMESPACE