Method GenerateLookupTable

Modules/Multilabel/src/mitkLabelSetImageVtkMapper2D.cpp:99–163

}

void mitk::LabelSetImageVtkMapper2D::GenerateLookupTable(mitk::BaseRenderer* renderer)
{
  LocalStorage* localStorage = m_LSH.GetLocalStorage(renderer);
  mitk::DataNode* node = this->GetDataNode();
  auto* image = dynamic_cast<mitk::MultiLabelSegmentation*>(node->GetData());
  assert(image && image->IsInitialized());

  localStorage->m_LabelLookupTable = image->GetLookupTable()->Clone();
  auto lookUpTable = localStorage->m_LabelLookupTable->GetVtkLookupTable();
  const auto labelValues = image->GetAllLabelValues();

  mitk::IntVectorProperty::Pointer prop = dynamic_cast<mitk::IntVectorProperty*>(node->GetNonConstProperty(LabelHighlightGuard::PROPERTY_NAME_LABELS_HIGHLIGHTED()));
  const auto highlightedLabelValues = prop.IsNotNull() ? prop->GetValue() : std::vector<int>({});
  const auto highlightEnd = highlightedLabelValues.cend();
  const bool highlightingActive = !highlightedLabelValues.empty();

  mitk::BoolProperty::Pointer boolProp = dynamic_cast<mitk::BoolProperty*>(node->GetNonConstProperty(LabelHighlightGuard::PROPERTY_NAME_HIGHLIGHT_INVISIBLE()));
  const bool highlightInvisibleLabels = boolProp.IsNull() ? false : boolProp->GetValue();

  float nodeOpacity = 1.0f;
  node->GetOpacity(nodeOpacity, renderer, "opacity");
  const float opacityFactor = this->GetOpacityFactor();

  // Node "opacity" times the "opacity factor" preference define the base (normal)
  // opacity. It is baked into the LUT alpha here rather than applied at the layer actor,
  // so a hovered label can be spotlit above the base (see GenerateDataForRenderer, which
  // keeps the actor opacity fixed at 1.0).
  const double base = static_cast<double>(nodeOpacity) * opacityFactor;

  double rgba[4];
  for (const auto& value : labelValues)
  {
    lookUpTable->GetTableValue(value, rgba);

    // The segmentation LUT stores each label's own opacity in alpha (0 = hidden).
    const double labelOpacity = rgba[3];
    const double normalOpacity = labelOpacity * base;

    if (highlightingActive)
    {
      const bool isHighlightedValue = highlightEnd != std::find(highlightedLabelValues.begin(), highlightedLabelValues.end(), value);
      if (isHighlightedValue)
      {
        // Spotlight the hovered label at full opacity, decoupled from the base so it
        // pops regardless of how transparent the segmentation is. A hidden label is
        // only revealed when explicitly requested (Shift-highlight of invisible labels).
        rgba[3] = (labelOpacity != 0.0 || highlightInvisibleLabels) ? HIGHLIGHTED_LABEL_OPACITY : 0.0;
      }
      else
      {
        // Fade the other labels to a low floor, but never above their normal appearance.
        rgba[3] = std::min(FADED_LABEL_OPACITY, normalOpacity);
      }
    }
    else
    {
      rgba[3] = normalOpacity;
    }