PACDisplay - Text/objects being covered up ? - old forum post


#1

ebahr

Joined on 06-24-2008
Posts 10
PACDisplay - Text/objects being covered up/erased by refreshing text or graphs?

I don’t know if anyone else is having a problem with this, but I just thought I would post my experience to hopefully help someone else out. The problem I was having is that whenever a graph or text block that refreshes periodically was in the vicinity of another text block or object, it would cover up or erase part of the stationary text even if the z-order of the stationary object was on top of the refreshing object. Here are some pictures of examples of what I am talking about

Refreshing Graph:

Good: http://lh5.ggpht.com/_DysGpEDSW-c/SW0IV0YYPOI/AAAAAAAAAFY/QF5XecpoSb4/s800/graph-good.JPG

Bad: http://lh5.ggpht.com/_DysGpEDSW-c/SW0IVyOsf3I/AAAAAAAAAFQ/yowKgFhU6DE/s800/graph-bad.JPG

Changing text (the word TESTING changes periodically):

Good: http://lh6.ggpht.com/_DysGpEDSW-c/SW0IWO8gNmI/AAAAAAAAAFo/uKj4gezZFwU/s800/text-good.JPG

Bad: http://lh6.ggpht.com/_DysGpEDSW-c/SW0IVxx9hQI/AAAAAAAAAFg/Q7s_l7YUR1M/s800/text-bad.JPG

I was told that this is a problem with Windows, and not PAC Display. The fix I have been using is to create a box with invisible fill and lines and have the z-order on top of everything and positioned on top of the objects. I then set the dynamic attributes of the box to Visibility/Blink and set it to Fast Blink for a dummy variable in PAC Control. This seems to keep all the z-order levels in check and if there are any cover-ups, they are fixed as fast as it takes for the box to blink again.

Hope this helps somebody.

-Eric

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01-16-2009, 10:55 AM

ben orchard

Joined on 12-08-2004
Posts 33
Re: PACDisplay - Text/objects being covered up/erased by refreshing text or graphs?

Eric,

Thanks for the tip. Pretty interesting work around.

The thing to keep in mind is that PAC Display adds 2-3 pixels (it depends on the original shape) to the edge of all its graphics.
It does this to keep Windows happy when it does a redraw of the screen.
So, if you allow for this by keeping 4-6 pixels between your shapes/text/images, you don’t see the overlap.

Just something to keep in mind when you are designing your screens.

Ben.