TGeoMedium* KVMaterial::GetGeoMedium(const Char_t* med_name)
{
// By default, return pointer to TGeoMedium corresponding to this KVMaterial.
// If argument "med_name" is given and corresponds to the name of an already existing
// medium, we return a pointer to this medium, or 0x0 if it does not exist.
// med_name = "Vacuum" is a special case: if the "Vacuum" does not exist, we create it.
//
// Instance of geometry manager class TGeoManager must be created before calling this
// method, otherwise 0x0 will be returned.
// If the required TGeoMedium is not already available in the TGeoManager, we create
// a new TGeoMedium corresponding to the properties of this KVMaterial.
// The name of the TGeoMedium (and associated TGeoMaterial) is the name of the KVMaterial.
if (!gGeoManager) return NULL;
if (strcmp(med_name, "")) {
TGeoMedium* gmed = gGeoManager->GetMedium(med_name);
if (gmed) return gmed;
else if (!strcmp(med_name, "Vacuum")) {
// create material
TGeoMaterial* gmat = new TGeoMaterial("Vacuum", 0, 0, 0);
gmat->SetTitle("Vacuum");
gmed = new TGeoMedium("Vacuum", 0, gmat);
gmed->SetTitle("Vacuum");
return gmed;
}
return NULL;
}
// if object is a KVDetector, we return medium corresponding to the active layer
if (GetActiveLayer()) return GetActiveLayer()->GetGeoMedium();
// for gaseous materials, the TGeoMedium/Material name is of the form
// gasname_pressure
// e.g. C3F8_37.5 for C3F8 gas at 37.5 torr
// each gas with different pressure has to have a separate TGeoMaterial/Medium
TString medName;
if (IsGas()) medName.Form("%s_%f", GetName(), GetPressure());
else medName = GetName();
TGeoMedium* gmed = gGeoManager->GetMedium(medName);
if (gmed) return gmed;
TGeoMaterial* gmat = gGeoManager->GetMaterial(medName);
if (!gmat) {
// create material
gmat = GetRangeTable()->GetTGeoMaterial(GetName());
gmat->SetPressure(GetPressure());
gmat->SetTemperature(GetTemperature());
gmat->SetTransparency(0);
gmat->SetName(medName);
gmat->SetTitle(GetName());
}
// create medium
static Int_t numed = 1; // static counter variable used to number media
gmed = new TGeoMedium(medName, numed, gmat);
numed += 1;
return gmed;
}
