Panels and/or layers
Ronald Wiemer
RWIEM at archis.nl
Thu Jun 29 08:00:00 EDT 1995
> Greetings,
>
> I'm looking for a way to set up a series of GRASS panels or layers
> that can somehow be defined to the driver and subsequently
> re-displayed quickly.
>
> The need for this arises from a requirement that I display a large
> number of icons (hundreds of thousands) against a background of mainly
> vector data, but also potentially raster images. Currently, if I
> change the background, I do it by erasing and re-drawing raster
> images, then vectors, and finally icons.
>
> Re-drawing hundreds of thousands of icons (from data extracted from a
> binary file) can take several minutes. Since this involves re-drawing
> data that hasn't changed, it seems like there should be a fast way to
> do it, by exploiting power available in the GRASS driver.
>
> In poking around the GRASS source code, I found C procedures to save
> and restore panels. But the save_panel procedure seems to save only
> that data currently on the screen. I need to save/redraw some of the
> data and re-generate other data. Or better: I need to segment the
> data into different panels or layers and be able re-display them at
> will.
>
> My goals may be achievable if I could do something like this:
>
> draw vectors to a panel
> display vector panel
> draw icons to a panel
> display icon panel
>
> later:
>
> erase screen
> draw new vectors to the vector panel
> display vector panel
> re-display existing icon panel
>
> Can anyone offer helpful suggestions? Thanks.
>
> - Bob
>
> ---
> Robert A. Black
> Principal Engineer
> Calspan Advanced Technology Center
> Calspan Corporation
> 4455 Genesee St.
> Buffalo, NY 14120
>
What you can do, is converting the sites to raster and then use
d.rast -o to display them on any background you like.
Ronald Wiemer
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