Rolfe wrote:
> I'm already using a picture data type with shift registers to
> incrementally add points. This is not a viable solution because, as
> you will see if you delve into the the picture function VIs, pictures
> merely consist of a series of concatenated strings which describe how
> to construct the desired image. Thus, a picture which contains
> thousands or millions of overlapping points explictly contains and
> must draw each and every one of those points, even if they only cover
> a small number of pixels. It is these overlapping points of a picture
> built using a shift register, and the slow speed at which they are
> rendered when the composite picture is displayed via a front-panel
> picture indicator, which is slowing down my a
pplication to an
> unworkable degree. Please refer to my original posting for a complete
> description of the problem.
The Picture Control has an update mode. A Property node "Erase First"
allows you to set if the Control should erase always, never or just this
single time. The pop-up for the Picture Control only has a checkmark for
this option mean ing erase always of never for obvious reasons. You can
set the Control to never clear its data, and then just adding the newly
added points (draw primitives) to the Picture Control will draw over all
previously painted data if necessary not cleaning the internal bitmap at
all before doing so.
Then whenever you decide you want to start completely new you execute
the Property Node "Erase First:Erase Once now".
Rolf Kalbermatter
Rolf Kalbermatter
My Blog 
DEMO, Electronic and Mechanical Support department, room 36.LB00.390