C++ (Cpp) Sample::setVals Examples

Example #1

File: Emitter.cpp Project: NCCA/SimulationExports

void Emitter::exportFrame()
{
  static int frame=0;
  ++frame;
  // this is the data we are going to store, alembic uses Imath
  // internally so we convert from ngl
  // this is the array of particle positions for the frame
  std::vector<Imath::V3f> positions(m_numParticles);
  // these are the particle id's which are required so use use index no
  std::vector<Alembic::Util::uint64_t> id(m_numParticles);
  // set this to push back into the array
  Imath::V3f data;
  // colour values
  std::vector<Imath::V3f> colours(m_numParticles);

  std::vector<Imath::V3f> velocities(m_numParticles);
  std::vector< Alembic::Util::float32_t > widths;
  AbcG::OFloatGeomParam::Sample widthSamp;
  widthSamp.setScope(Alembic::AbcGeom::kVertexScope);
  widthSamp.setVals(Alembic::Abc::FloatArraySample(widths));

  for(size_t  i=0; i<m_numParticles; ++i)
  {
    positions[i]=Imath::V3f(m_particles[i].m_px,m_particles[i].m_py,m_particles[i].m_pz);
    id[i]=i;
    colours[i]=Imath::V3f(m_particles[i].m_r,m_particles[i].m_g,m_particles[i].m_b);
    velocities[i]=Imath::V3f(m_particles[i].m_r,m_particles[i].m_g,m_particles[i].m_b);
  }
  // create as samples we need to do this else we get a most vexing parse
  // https://en.wikipedia.org/wiki/Most_vexing_parse using below
  // psamp(V3fArraySample( positions),UInt64ArraySample(id))
  AbcG::V3fArraySample pos(positions);
  AbcG::UInt64ArraySample ids(id);
  AbcG::OPointsSchema::Sample psamp( pos,ids,velocities );
  AbcG::OPointsSchema &pSchema = m_partsOut->getSchema();
  std::cout<<"Schema "<<pSchema.getNumSamples()<<" "<<pSchema.valid()<<"\n";

  pSchema.set( psamp );
  AbcG::V3fArraySample colourArray(colours);


  m_rgbOut->set(colourArray);

}

Example #2

File: MayaPointPrimitiveWriter.cpp Project: alembic/alembic

void MayaPointPrimitiveWriter::write(double iFrame)
{
    MStatus status;
    std::vector<float> position;
    std::vector<float> velocity;
    std::vector< Alembic::Util::uint64_t > particleIds;
    std::vector<float> width;

    bool runupFromStart = false;
    MTime to(iFrame, MTime::kSeconds);

    // need to force re-evaluation
    MFnParticleSystem particle(mDagPath);
    particle.evaluateDynamics(to, runupFromStart);

    unsigned int size = particle.count();

    Alembic::AbcGeom::OPointsSchema::Sample samp;

    if (size == 0)
    {
        samp.setPositions(Alembic::Abc::V3fArraySample(NULL, 0));
        samp.setVelocities(Alembic::Abc::V3fArraySample(NULL, 0));
        samp.setIds(Alembic::Abc::UInt64ArraySample(NULL, 0));

        mSchema.set(samp);
        return;
    }

    position.reserve(size*3);
    velocity.reserve(size*3);
    particleIds.reserve(size);
    width.reserve(size);

    // get particle position
    MVectorArray posArray;
    particle.position(posArray);
    for (unsigned int i = 0; i < size; i++)
    {
        MVector vec = posArray[i];
        position.push_back(static_cast<float>(vec.x));
        position.push_back(static_cast<float>(vec.y));
        position.push_back(static_cast<float>(vec.z));
    }
    samp.setPositions(
        Alembic::Abc::P3fArraySample((const Imath::V3f *) &position.front(),
            position.size() / 3) );

    // get particle velocity
    MVectorArray vecArray;
    particle.velocity(vecArray);
    for (unsigned int i = 0; i < size; i++)
    {
        MVector vec = vecArray[i];
        velocity.push_back(static_cast<float>(vec.x));
        velocity.push_back(static_cast<float>(vec.y));
        velocity.push_back(static_cast<float>(vec.z));
    }
    if (!velocity.empty())
    {
        samp.setVelocities(
            Alembic::Abc::V3fArraySample((const Imath::V3f *) &velocity.front(),
                velocity.size() / 3) );
    }

    // get particleIds
    MIntArray idArray;
    particle.particleIds(idArray);
    for (unsigned int i = 0; i < size; i++)
    {
        particleIds.push_back(idArray[i]);
    }
    samp.setIds(
        Alembic::Abc::UInt64ArraySample(&(particleIds.front()),
            particleIds.size()) );

    // assume radius is width
    MDoubleArray radiusArray;
    MPlug radius = particle.findPlug("radiusPP", true, &status);
    AbcGeom::GeometryScope widthScope = AbcGeom::kUnknownScope;
    if ( status == MS::kSuccess)
    {
        // RadiusPP exists, get all particles value
        widthScope = AbcGeom::kVaryingScope;
        particle.radius(radiusArray);
        for (unsigned int i = 0; i < size; i++)
        {
            float radius = static_cast<float>(radiusArray[i]);
            width.push_back(radius);
        }
    }
    else
    {
        // Get the value of the radius attribute
        widthScope = AbcGeom::kUniformScope;
        width.push_back( particle.findPlug("radius").asDouble() );
    }


    if (!width.empty())
    {
        Alembic::AbcGeom::OFloatGeomParam::Sample widthSamp;
        widthSamp.setVals(width);
        widthSamp.setScope(widthScope);
        samp.setWidths( widthSamp );
    }

    mSchema.set(samp);
}