Visible lag while drawing line with the digitizer tool

vax

Hi Mike,

recently I noticed that drawing a line with the digitizer tool is much slower compared to what it was before.

There is definitely a visible lag if you click and draw a new line quickly. A dot-style cursor appears up to 1 cm ahead from the line that is drawn. This lag also affects precision as some clicks are lost on the way.

global_mapper

This was an issue in the v13.2.0 release when clicking near complex lines due to the new "snap to intersection" functionality. This is now significantly improved and shouldn't be noticeable anymore in the v13.2.2 release, which is available from the links below:

32-bit: http://www.globalmapper.com/downloads/global_mapper_setup.exe
64-bit: http://www.globalmapper.com/downloads/global_mapper_setup_64bit.exe

Thanks,

Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com

vax

Hello Mike,

I installed the new build from the link you gave me but I could not see significant difference.
I suspect that the problem is not exactly you speak about.

Lagging is present near lines, but they are not complex. They are not also intersecting, etc.
I also cannot see some dependency if there is a raster visible or only vector objects. Simply the line drawn lags behind the cursor 1-2 cm and clicking vertices doesn't catch every click but miss some.

global_mapper

Is it just snapping in general that is the cause of confusion? Whenever your cursor is near a line, area, or point it will tend to snap to that point and you will see a little dot where the snap would go. If you don't want the snapping to occur you can hold down the ALT key or disable it by default on the Vector Display tab of the Configuration dialog. The snapping behavior has always been there, it can just now also snap to intersections and you also get a little dot to show you where the snap would be to. I suspect it is the new little snap locator dot that is causing the confusion.

Thanks,

Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com

vax

Hm I think I've got the steps to reproduce the problem.

Here what I did - I make a rough sketch of the river and stream network using 1:50000 maps, all in vectors.
Then I open this vector sketch with a ortophoto raster behind and begin drawing the real river & stream network from the photos. The sketch I use is only as a reminder where the rivers pass according to the 1:50k maps.

I usually hold ALT while drawing to avoid new line snap to the sketched river vectors. My newly drawn river lines are usually nearby the sketch lines.

The lag problem is very pronounced when the cursor is close to the sketch vector line. I even made a test to draw a quick zig-zag around the sketch line and guess what - the real drawing appeared several seconds after I clicked all around.

It is interesting, that this problem is also present in v.12.2, just tested it.

Here is a screenshot of what I did. Just try to click the zig-zag line in 2-3 seconds:

Clipboard15.jpg

global_mapper

I am so far unable to reproduce any lag in v13.2.2 when tracing near existing features with another image layer loaded as background, whether snapping is enabled or not. If you are seeing the same thing in v12.02 then the new 'snap to intersection' functionality couldn't be the culprit anyway. Do you have a very large amount of vector data loaded? What is the format of your background imagery and is that all that you have loaded in the background? Are there any large background polygons or anything like that?

Thanks,

Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
http://www.globalmapper.com