void Histogram::add(const Histogram& hist)
{
assert(hist.getBins() == m_bins);
assert(hist.getBinSize() == -1); // assume log histogram
assert(m_binsize == -1);
for (int j = 0; j < hist.getData(0); j++) {
add(0);
}
for (int i = 1; i < m_bins; i++) {
for (int j = 0; j < hist.getData(i); j++) {
add(1<<(i-1)); // account for the + 1 index
}
}
}
void execute(const FutureMap& input, PromiseMap& output) const
{
const auto& frustums = input.get<Frustum>("Frustum");
const auto& viewports = input.get<Viewport>("RelativeViewport");
auto dataSourceRange = input.get<Vector2f>("DataSourceRange").front();
const auto& frustum = frustums.front();
const auto& viewport = viewports.front();
Histogram histogramAccumulated;
for (const auto& cacheObjects : input.getFutures("CacheObjects"))
for (const auto& cacheObject :
cacheObjects.get<ConstCacheObjects>())
{
const CacheId& cacheId = cacheObject->getId();
// Hist cache object expands the data source range if data has
// larger values
ConstHistogramObjectPtr histCacheObject =
_histogramCache.load<HistogramObject>(cacheId, _dataCache,
_dataSource,
dataSourceRange);
if (!histCacheObject)
continue;
const Vector2f& currentRange =
histCacheObject->getHistogram().getRange();
if (currentRange[0] < dataSourceRange[0])
dataSourceRange[0] = currentRange[0];
histogramAccumulated.setMin(dataSourceRange[0]);
if (currentRange[1] > dataSourceRange[1])
dataSourceRange[1] = currentRange[1];
histogramAccumulated.setMax(dataSourceRange[1]);
const size_t currentBinCount =
histCacheObject->getHistogram().getBins().size();
if (histogramAccumulated.getBins().empty())
histogramAccumulated.resize(currentBinCount);
// When a frame is rendered in multi-channel, multi-node, etc
// config, some nodes are rendered twice in sort-first
// renderings
// To avoid counting nodes twice, we check if the center of the
// node is in
// this frustum (because it can only be in one tile at a time).
// For viewports
// on the border of the absolute viewport, the frustum is
// virtually extended
// to infinity on the boundary.
try
{
const LODNode& lodNode =
_dataSource.getNode(NodeId(cacheId));
if (isCenterInViewport(frustum, lodNode.getWorldBox(),
viewport))
histogramAccumulated += histCacheObject->getHistogram();
}
catch (const std::runtime_error&)
{
// Only compatible histograms can be added.( i.e same data
// range and number of
// bins.) Until data range converges to the full data range
// combined from other
// rendering clients, the cache objects are purged from the
// cache.
_histogramCache.purge(cacheId);
}
}
output.set("Histogram", histogramAccumulated);
}