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Coordinates arrow cursor - vector graphics

Posted: Thu Jul 23, 2020 1:30 am
by Victorio
Hi.
I am simple creating viewer/editor for digital maps and have some problems with justify coordinates.
I must recalculating coordinates from screen pixels to cadastral coordinates, this works correct.

But I do not know how I can programatically change cursor type arrow to cross. I know this can change in windows settings but can this change from my app ?
And other problem when I have cursor type arrow and pict to some point, his coordinates is not direct on spike arrow, but some in arrow. How can calculate exactly where is center of arrow ?
Now I must use some coeficient to modify pick point, but this can be not same on other PC with other screen resolution.

Re: Coordinates arrow cursor - vector graphics

Posted: Mon Jul 27, 2020 1:19 pm
by rdonnay
You need to add your cross cursor to your .ARC file.

Look at \exp20\lib\express.arc to see how pointers are added.
You will need to fine the appropriate *.CUR file for your cross.

If you are using eXpress++ commands to make your parent object for your vector graphics, then use the CURSOR clause of the DC* command to assign the cursor, otherwise you will need to use <obj>:setPointer(nCursor).

If using eXpress++, you would use a custom handler with the DCREAD GUI .. HANDLER clause, to test the xbeM_Motion event, otherwise if you have your own event loop you can do it with the AppEvent() function. This would give you the cursor coordinates.

Re: Coordinates arrow cursor - vector graphics

Posted: Tue Jul 28, 2020 12:49 am
by Victorio
Roger, thank you very much, this (express.arc) I am searching.
I will try it.