SampleInfo getSampleInfo
(
double iFrame,
Alembic::AbcCoreAbstract::TimeSamplingPtr iTime,
size_t numSamps
)
{
ESS_PROFILE_SCOPE("getSampleInfo");
SampleInfo result;
if (numSamps == 0)
numSamps = 1;
std::pair<Alembic::AbcCoreAbstract::index_t, double> floorIndex = iTime->getFloorIndex(iFrame, numSamps);
result.floorIndex = floorIndex.first;
result.ceilIndex = result.floorIndex;
if (fabs(iFrame - floorIndex.second) < 0.0001) {
result.alpha = 0.0f;
return result;
}
std::pair<Alembic::AbcCoreAbstract::index_t, double> ceilIndex =
iTime->getCeilIndex(iFrame, numSamps);
if (fabs(iFrame - ceilIndex.second) < 0.0001) {
result.floorIndex = ceilIndex.first;
result.ceilIndex = result.floorIndex;
result.alpha = 0.0f;
return result;
}
if (result.floorIndex == ceilIndex.first) {
result.alpha = 0.0f;
return result;
}
result.ceilIndex = ceilIndex.first;
result.alpha = (iFrame - floorIndex.second) / (ceilIndex.second - floorIndex.second);
return result;
}
double getWeightAndIndex(double iFrame,
Alembic::AbcCoreAbstract::TimeSamplingPtr iTime, size_t numSamps,
Alembic::AbcCoreAbstract::index_t & oIndex,
Alembic::AbcCoreAbstract::index_t & oCeilIndex)
{
if (numSamps == 0)
numSamps = 1;
std::pair<Alembic::AbcCoreAbstract::index_t, double> floorIndex =
iTime->getFloorIndex(iFrame, numSamps);
oIndex = floorIndex.first;
oCeilIndex = oIndex;
if (fabs(iFrame - floorIndex.second) < 0.0001)
return 0.0;
std::pair<Alembic::AbcCoreAbstract::index_t, double> ceilIndex =
iTime->getCeilIndex(iFrame, numSamps);
if (oIndex == ceilIndex.first)
return 0.0;
oCeilIndex = ceilIndex.first;
double alpha = (iFrame - floorIndex.second) /
(ceilIndex.second - floorIndex.second);
// we so closely match the ceiling so we'll just use it
if (fabs(1.0 - alpha) < 0.0001)
{
oIndex = oCeilIndex;
return 0.0;
}
return alpha;
}