Hi, My colleague has met the problem that the performance of event display is very low. Up to now a two dimensional histogram (TH2S, with channels and samples as histogram bins and the signal amplitude, for a given channel and sample, as a weight for the histogram entry) is used for the event display. The problem is that in case of a large amount of channels and samples (and this is the usual case) this method is very slow, and one as to wait several minutes to have the histogram plotted (almost independently from the machine, single and double PIII up to 750 MHz and ATHLON 1.2 GHz give the same result). We are looking for a way to improve it (significantly). We think that, most probably, the best thing to do is to create a pixmap or bitmap image, and plot it directly . There are methods like "CreatePictureFromData", "CreatePixmap" and "CreateBitmap"in the TGX11/TVirtualX (with the implementation in GX11Gui.cxx). Do you have any hints on how to integrate this approach with ROOT ? Or maybe you have any other suggestions ? Thanks in advance, Best regards, Jacek.
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