Re: High spped drawing with MFC is it possible?

that I have is whenever window needs update it takes considerable time for
window to redraw(even on a very fast computer) and it can be frustrating for
user. Data drawing function first calculates the location of point on screen
then uses pDC->LineTo() and pDC->MoveTo() functions to draw the plot. Well,
because of amount of data many points will overlap. When I modified the
algorithm so that it first determines whether a point overlaps other points
and if it does, skip this point then performance improved but still not
satisfactory.

So, how many lines are you actually drawing with your refined
algorithm? Have you tried using PolylineTo rather than drawing them
all individually?

I suspect that you need to profile your application to determine where
the lack of speed derives from - it may not be in the drawing itself
since you indicate that your improved algorithm hasn't made a
substantial difference.

Dave
.

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