Thanks for turning greens/fairways into proper multipolygons!

Not cool. Don't do this again.

Hey there ER, thanks for working on golf course contributions for OSM. We appreciate the map getting filled out.

There is a problem with how you're mapping though (e.g. osm.org/way/1363133822). You are making the fairway (and rough) intersect/partial-overlap with the green which isn't how they are supposed to be mapped. You either need to butt the fairway up against the green and share common nodes, or you need to surround the green (if there is visible fringe matching the fairway) and turn the fairway/green pair into a multipolygon ("Merge" features in iD). Please see the wiki for more information: osm.wiki/Tag:leisure%3Dgolf_course and feel free to reach out with any questions you have. Thanks.

Hi golfboy,

Why did you add a second, nearly identical green here: osm.org/way/1363208624 ?

Also, you put two fairway areas next to each other. These should be a single object and the fairway/green should be combined/merged into a multipolygon. Check out the wiki at osm.wiki/Tag:leisure%3Dgolf_course for how to properly map these together. Let me know if you have any questions.

Thanks for getting back to me mech32. Can you confirm with me that you understand how relationships and multipolygons work? It wasn't quite clear from your comment that you understood that and how to avoid breaking them. Thanks.

On Hole 11, you shouldn't use multiple polygons to make up a single fairway. Read the wiki (osm.wiki/Tag:leisure%3Dgolf_course) for how to map bunkers and fairways and green properly using multipolygons with inner/outer relationships. If you have any questions, please feel free to reach out and I'll help clarify.

Hey there mech32, thanks for helping out with golf course mapping. We appreciate the work, but I wanted to point out some issues.

You have breaking relationships between features. This is caused by you deleting something like a fairway boundary that is part of a multipolygon and then recreating, but leaving the relationship around with only the green as part of it.

It's a bad idea to delete features and recreate them from scratch. They should be modified if at all possible. If this is too difficult with the iD editor, maybe use something like JOSM. And if you must delete something, make sure it isn't part of a multipolygon first and if it is, properly recreate the multipolygon after your edits.

Please read up on osm.wiki/Tag:leisure%3Dgolf_course#Common_mapping_pitfalls to better understand. If you have any comments, please reach out and I'll clarify. Thanks.

Hi Averytt10, thanks for contributing to OSM and improving golf course maps. I wanted to let you know about some best practices before you do any more mapping.

You shouldn't create bunkers that intersect with fairways. By doing so, you are saying that any area that they overlap is somehow considered both sand and grass, which doesn't make sense. The fairway needs to be adjusted to no intersect. Depending on what you see in imagery, the fairway should go around in such a way as to include or exclude the bunker. If the fairway completely surrounds the bunker, you need to combine the two objects into a multipolygon.

The same thing can be said about greens and fairways. They shouldn't be intersecting and partially overlapping.

You might want to read over the wiki to see examples of how to map golf course features: osm.wiki/Tag:leisure%3Dgolf_course

Thanks.

Thank you! Thank you for reusing old features instead of deleting and recreating. I've been chasing down others this morning that have been breaking things when they delete features improperly.

Good morning J,

It's a bad idea to delete golf course elements that you simply want to modify the geometry of. It's best to preserve the history and attributes whenever possible. For example, you deleted the fairway on Hole 10 and then recreated a nearly identical object. The problem is that the fairway was part of a multipolygon relationship the included the fairway and the green, but now that relationship is broken and the green remains in an error state.

Please be careful not to break relationships/multipolygons in the future. Or if you do, make sure you recreate them in the end. Thanks!

Those are some good looking golf course edits! In chance you want to help me with more golf courses? Check out mpr.lt/c/50926

Hi there Course,

I noticed that you tried to make the fairway and green get very close to each other without actually touching. It is very important that they don't overlap, but it is equally important that there is no gap between them (except for those golf courses where the greens are specifically manicured to be separated from the fairway). But in the case of this particular hole, the fairway and greens should be sharing the same nodes at their boundary, not inches away from each other.

For more information, see the wiki page for golf courses at osm.wiki/Tag:leisure%3Dgolf_course#Common_mapping_pitfalls

Thanks.

Thanks for responding to the feedback. Overlapping is bad, but so is "almost touching". What you should be doing is sharing the nodes between the green and the fairway. Take a look at the wiki (osm.wiki/Tag:leisure%3Dgolf_course#Common_mapping_pitfalls) for examples. I've gone ahead and fixed osm.org/way/1361164081 if you want to look at that for an example.

Can you show me where you were advised to do the overlapping? We're trying to catch bad instructions going out at the source so we can get things done correctly from the start. When someone says to do something because it "shows better", that is called "mapping for the renderer" and not necessarily mapping correctly. We want to make sure the map is correct, not just that it "looks good".

Thanks.

Very cool. We always appreciate good golf course mapping. Be sure and read the wiki to find other great tips on mapping courses: osm.wiki/Tag:leisure%3Dgolf_course

Thanks for the contributions Ratelimiter. FYI, greens that don't have specific names (very rare) shouldn't have "#2 Green" added to them. The name should be left unset. You can put "ref=2" on the feature, but if there is already the straight line golf "hole" with proper "ref" tagging, putting one on the green is redundant. Thanks.

Hey there mbuenger,

Please see the OSM wiki on mapping golf courses. You shouldn't have fairways and green intersecting or partially overlapping each other.

osm.wiki/Tag:leisure%3Dgolf_course#Common_mapping_pitfalls

Thanks.

Hi Yuliya,

Why remove the service=parking_aisle tag on what is clearly a route through rows of parking spots?

Thanks for helping clean up some bad golf mapping!

Hi Bobby,

Thanks for helping the OSM community improve golf course mapping. There's a small problem with how you mapped the first hole (and possibly others) that I wanted to let you know about so that you change how you do it in the future.

The way that it was before is super-wrong, so I'm glad you're working on improving it. The fairway had been marked in such a way that it intersected the green and partially overlapped it. What you did was made the fairway go all the way around the green and you reused the nodes of the green. The problem with what you did is that it isn't topologically correct. There are two ways to handle the green. The first is that, if you can see it in satellite imagery, leave room between the fairway and green. This is called the "fringe" and isn't always obvious from imagery. And when the fairway fully surrounds the green, it should be turned into a multipolygon. The second way is to make the fairway butt up against the green by sharing nodes between them, but exclude the area of the green instead of surrounding it.

This is a wiki page that describes how to do the above: osm.wiki/Tag:leisure%3Dgolf_course

Let me know if you have any questions.

On rereading your sentence, if you are selecting multiple greens and multiple fairways and grouping them once, that won’t work. You need to select one enclosing fairway, and anything that is fully contained within that fairway and group just those together.