[vtkusers] abnormal chart using scatter points

[liuxy]

I used vtkChart API to draw a line: y=sin(x) using "scatter points",

the chart is abnormal when the number of points are more than 40,000.

just like pictrue a.jpg in enclosure.

but if the points are less than 40,000 or using "Line" to draw y=sin(x),

the chart is correct. Just like pictrue b.jpg.

I want to know how to use "scatter points" in drawing charts with huge scale
of points ?

or vtkChart may be not applicable in this situation ?


P.S:

By reading the source Code of vtkChart,

I found when drawing in "scatter points",

it used function 'DrawPointSprites'.

if replaced it with function 'DrawPoints',the chart shows correctly,

even number of points more than 40,000.
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