BCGControlBar Pro for MFC
void CBCGPChartLongSeries::SetFilterSimilarXValues ( BOOL  bSet = TRUE)

Optimizes performance by displaying average calculated among all Y values falling on the same pixel.

Call this method to optimize performance and reduce some "noise" on the diagram, which appears as a result of several Y values being displayed on the same pixel.

bSetTRUE - turn the optimization on; FALSE - turn the optimization off.