开云体育

Alas, I suspect that you're not being patient enough for topo lines to be rendered. I just tried it as well, and found that it took 336 seconds (!) on my older server computer to render over a view spanning 0.7x0.4 degrees. Apparently, the Graphics2D.drawPolyline() method in the Java runtime library has slowed down immensely, and that is what is used to draw all the squiggly contour lines. And, if you pan or zoom the map, all the incomplete work put into rendering for the previous map is tossed out and started over for the new map coverage.

Just out of curiosity, what version of the Java runtime are you using? And how much RAM does your computer have?

Of course, it doesn't help that the process of rendering vector contour lines from raster elevation data is computationally intensive as well, because that is also a contributor, though I have done everything I can to make that part of the algorithm faster (since that, at least, is in my code in YAAC rather than in Oracle's Java libraries or your operating system's graphics subsystem).

I would recommend that you switch to using topographic contour regions rather than lines; they are much faster to compute. In the meantime, I will look at ways to improve the performance of this code.

Andrew, KA2DDO
author of YAAC

________________________________________
From: [email protected] <[email protected]> on behalf of David Lowry via groups.io <huskyrunnr@...>
Sent: Tuesday, December 31, 2024 12:56 PM
To: [email protected]
Subject: [yaac-users] Can’t get topo lines

I’m running YAAC 1.0-beta205 on Windows 10, but a previous version behaved the same. I can successfully download pre-imported OSM tiles. I can successfully download a small radius of the NASA topo data. I have correct lat/lon entered in the download dialog. When I toggle on view>layers>show topography>show topographic contour lines I get the citation to NASA in the lower right corner of the map but I can’t see any contour lines. I’m wondering what I’m missing. Thanks for any advice.
David

Contour regions are easy. Right above the menu choice to draw contour lines is the choice to fill contour regions. So uncheck contour lines and check contour regions instead. You might also want to edit the contour ranges (third choice on the submenu where you check and uncheck drawing topo contours) to get more contrast in the color changes between different elevation levels.

Hope this helps.

Andrew, KA2DDO
author of YAAC

________________________________________
From: [email protected] <[email protected]> on behalf of David Lowry via groups.io <huskyrunnr@...>
Sent: Tuesday, December 31, 2024 1:46 PM
To: [email protected]
Subject: Re: [yaac-users] Can’t get topo lines

Thank you! I’ll study how to implement contour regions. My Toughpad is 8 GB and Java is 23.0.1.
Best wishes for the new year!
David

Thank you for finding a bug in the OSM tile downloader. planet.ways.gz should have been named planet.ways; it's gzipped for transmission over the Internet and unzipped on reception (just like the other .ways files in the tiledir hierarchy), except that the renaming didn't happen upon the download of this particular file. This file is just a coarser version of the other .ways files so rendering can be much faster when zoomed way out (covering more than 60 square degrees of the planet).

Still working on optimizations for contour lines.

Andrew, KA2DDO
author of YAAC

________________________________________
From: [email protected] <[email protected]> on behalf of David Lowry via groups.io <huskyrunnr@...>
Sent: Tuesday, December 31, 2024 3:51 PM
To: [email protected]
Subject: Re: [yaac-users] Can’t get topo lines

Hmm, still no go. I went to tiledir and saw a 23 MB planet.ways.gz so I tried to extract it and got error ‘not an archive’. Also tried to repair the .gz with WinRAR and it just spits out a small .gz file with nothing in it when I try to extract it.

Not sure if planet.ways should remain zipped or if this is my issue.

A few other things to look at regarding rendering topographic contour lines:

Where are you trying to look at the map (geographically speaking)? You didn't specify your callsign so I couldn't guess at where you are located to see what kind of slopes you have in your area. The vertical spacing between contour lines is not dynamically computed, but rather set manually in the View->Layers->Show Topography->Edit Topographic Colors dialog box. So if you are:
a. zoomed out a lot, and
b. have steep slopes in the area to be rendered, and
c. have a small value for the contour interval setting,
the contour lines on those steep slopes will be mashed together because the horizontal distance between contour lines (in screen pixels) will be less than the pixel size. Also, the renderer has to check rendering lines for every possible contour line between the minimum and maximum elevations on the screen, so the smaller the spacing between contour lines, the longer it will take to compute the contour lines because more levels of them will have to be computed. And more uneven terrain will guarantee that more lines will be crossing slopes, increasing the computation for those additional contour lines.

So, if it is just taking forever to render the contour lines and you are looking at hilly terrain, try enlarging the contour interval to reduce the computation.

Hope this helps.

Andrew, KA2DDO
author of YAAC


________________________________________
From: [email protected] <[email protected]> on behalf of David Lowry via groups.io <huskyrunnr@...>
Sent: Tuesday, December 31, 2024 6:57 PM
To: [email protected]
Subject: Re: [yaac-users] Can’t get topo lines

Resolved. Wrong password to reach the NASA data, yet looked like it was downloading so didn’t think to check. Thank you again, your words explained a lot that I did not know about using this function. I also got the repeater finder working. No window would pop up until I moved from the toughpad “recommended” resolution of 150% to 100%.
David