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IeegContact

Namespace: IEEGLIB  ·  Library: iEEG Library

#include <ieeg/ieeg_implantation.h>

struct IEEGLIB::IeegContact

One recording contact.

src/examples/ex_ieeg/main.cpp
// Contacts of one depth lead, 3.5 mm apart, in metres; the lead comes from the names
QVector<IeegContact> contacts;
for (int k : {3, 1, 2}) {
    IeegContact contact;
    contact.name = QStringLiteral("LA%1").arg(k);
    contact.position = Eigen::Vector3f(-0.03f, 0.0f, 0.0035f * float(k - 1));
    contacts.append(contact);
}
const IeegImplantation implantation(contacts, QStringLiteral("ACPC"));
const IeegLead& lead = implantation.leads().first(); // contacts ordered LA1, LA2, LA3
// IeegImplantation::readBids("sub-01_electrodes.tsv") reads the same from BIDS iEEG

Example​

Used in examples​

ex_disp3d_scene​

Disp3D scene data: sensor-to-surface interpolation, electrodes, MRI slices, video overlay and layers.

src/examples/ex_disp3d_scene/main.cpp, line 134
QVector<IeegContact> shaft(4); // LH1..LH4, 3.5 mm apart: grouped into the sEEG depth lead "LH"
for (int k = 0; k < 4; ++k) {
    shaft[k].name = QString("LH%1").arg(k + 1);
    shaft[k].position = Eigen::Vector3f(0.010f + 0.0035f * float(k), -0.020f, 0.005f); // surface RAS, metres
}
ElectrodeObject electrodes; // a view of the implantation, drawn by BrainView::setElectrodes()
electrodes.setImplantation(IeegImplantation(shaft));
electrodes.selectContact("LH3");
float contactDistance = 0.0f;
const int pickedContact = electrodes.intersect(QVector3D(0.017f, -0.020f, 1.0f), QVector3D(0.0f, 0.0f, -1.0f), contactDistance);
ok &= expect(electrodes.totalContactCount() == 4 && electrodes.selectedContact() == "LH3" && electrodes.contactStreams().instanceCount == 4 && electrodes.bodyStreams().instanceCount == 1 && electrodes.contactLabel(pickedContact) == "LH3 (depth lead LH)",
             "ElectrodeObject: 4 contacts on one shaft, a ray through LH3 picks it");

ex_ieeg​

IEEG library: group sEEG contacts into a lead, derive a bipolar montage and paint contact values onto a surface.

src/examples/ex_ieeg/main.cpp, line 64
// Contacts of one depth lead, 3.5 mm apart, in metres; the lead comes from the names
QVector<IeegContact> contacts;
for (int k : {3, 1, 2}) {
    IeegContact contact;
    contact.name = QStringLiteral("LA%1").arg(k);
    contact.position = Eigen::Vector3f(-0.03f, 0.0f, 0.0035f * float(k - 1));
    contacts.append(contact);
}
const IeegImplantation implantation(contacts, QStringLiteral("ACPC"));
const IeegLead& lead = implantation.leads().first(); // contacts ordered LA1, LA2, LA3
// IeegImplantation::readBids("sub-01_electrodes.tsv") reads the same from BIDS iEEG
ok &= expect(implantation.leads().size() == 1 && lead.name == "LA" && lead.type == IeegLeadType::Depth && lead.contacts == QVector<int>({1, 2, 0}),
             "IeegImplantation: one depth lead LA, ordered by contact number");

Authors of this file​