gridentity.cpp

//  gamma-viewer-3d - 3d visualization of sessions generated by gamma-analyzer
//  Copyright (C) 2017  Dag Robole
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.

#include "gridentity.h"

GridEntityXZ::GridEntityXZ(float y,
                           unsigned int count,
                           float interval,
                           const QColor &color,
                           Qt3DCore::QEntity *parent)
    :
      Qt3DCore::QEntity(parent),
      mMesh(new Qt3DRender::QGeometryRenderer(this)),
      mGeometry(new Qt3DRender::QGeometry(this)),
      mDataBuffer(new Qt3DRender::QBuffer(Qt3DRender::QBuffer::VertexBuffer, this)),
      mPositionAttribute(new Qt3DRender::QAttribute(this)),
      mMaterial(new Qt3DExtras::QPhongMaterial(this))
{
    int halfCount = count / 2;
    int numVerts = halfCount * 4 * 2; // number of lines * number of points per line
    float halfLength = interval * (float)halfCount;

    QByteArray vertexBuffer;
    vertexBuffer.resize(numVerts * 3 * sizeof(float));
    float *ptr = reinterpret_cast<float*>(vertexBuffer.data());

    int i = 0;
    float x = -interval * (float)halfCount;
    for(; i < (numVerts * 3) / 2; i += 6)
    {
        ptr[i] = x;
        ptr[i+1] = y;
        ptr[i+2] = -halfLength;

        ptr[i+3] = x;
        ptr[i+4] = y;
        ptr[i+5] = halfLength - interval;

        x += interval;
    }

    float z = -interval * (float)halfCount;
    for(; i < numVerts * 3; i += 6)
    {
        ptr[i] = -halfLength;
        ptr[i+1] = y;
        ptr[i+2] = z;

        ptr[i+3] = halfLength - interval;
        ptr[i+4] = y;
        ptr[i+5] = z;

        z += interval;
    }

    mDataBuffer->setData(vertexBuffer);

    mPositionAttribute->setAttributeType(Qt3DRender::QAttribute::VertexAttribute);
    mPositionAttribute->setBuffer(mDataBuffer);
    mPositionAttribute->setVertexBaseType(Qt3DRender::QAttribute::Float);
    mPositionAttribute->setVertexSize(3);
    mPositionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());

    mGeometry->addAttribute(mPositionAttribute);

    mMesh->setInstanceCount(1);
    mMesh->setIndexOffset(0);
    mMesh->setFirstInstance(0);
    mMesh->setVertexCount(numVerts);
    mMesh->setPrimitiveType(Qt3DRender::QGeometryRenderer::Lines);
    mMesh->setGeometry(mGeometry);
    addComponent(mMesh);

    mMaterial->setAmbient(color);
    addComponent(mMaterial);
}

GridEntityXZ::~GridEntityXZ()
{
    for(auto *node : childNodes())
    {
        if(auto entity = qobject_cast<Qt3DCore::QEntity *>(node))
        {
            entity->components().clear();
            entity->deleteLater();
        }
    }

    mMaterial->deleteLater();
    mPositionAttribute->deleteLater();
    mDataBuffer->deleteLater();
    mGeometry->deleteLater();
    mMesh->deleteLater();
}