LIDAR Tutorial 1 – Creating Green Contours in QGIS

Share your designing tips with other Designer's. Find answers to your problems using the APCD.
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linkster
Posts: 26
Joined: Mon Jun 13, 2022 12:12 am

LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by linkster »

LIDAR Tutorial 1 Green Contours.pdf
(3.9 MiB) Downloaded 44 times

I started to put this tutorial in a post but quickly ran into the 6 attachments limit per post. So I printed the tutorial as a .pdf and was glad that it was under the 4MB file size limit. I hope those interested find it useful and informative. The next tutorial I will write is to make a full course terrain in the APCD from a QGIS output.

If anyone finds errors in the tutorial or has any other ideas related to using QGIS for green contours let me know!
hopeless@golf
Posts: 20
Joined: Thu Aug 29, 2019 9:51 pm
Location: Stoney Creek, Ontario, Canada

Re: LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by hopeless@golf »

Linkster a good tutorial would be how to Hex edit the APCD to accept more than a 100,000 verts
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Adelade
Posts: 1052
Joined: Tue Aug 27, 2019 9:24 am

Re: LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by Adelade »

Excellent! Thank you so much for making this green tutorial :clapping:

I dont plan on using it yet because I dont have a course in mind to work on that seems to have Lidar/DEM available, but I definitely might sometime in the future if certain course projects come up. I dont really plan on putting the green contours into APCD, but moreso using them as a guide to identify the main features of greens and then making the greens by my "own hand" in APCD, based on them. Because while I agree that the source data is very accurate, I still caution against trusting that their direct result in APCD/Links will turn out fully accurate in terms of details. Thats not saying I recommend against using them in APCD (seems like a good idea), just that it will not turn out anywhere near as accurate as if using Strackaline 1-inch charts for example. That said, I had expected the Chambers Bay 18th to have even more orange/red on the slope colour image than it did, so perhaps the method doesnt come that far behind green chart methods, but it also should be noted that more details will be lost in the conversion into APCD, since Vert height dont translate to exact ground level unless Edges are made sharp.

Anyway, I still went through the whole guide now to see if I'd understand, and I must admit I felt pretty confused through a lot of it. Not that the instructions were bad or anything, just that Im very unfamiliar with a lot of the stuff. Im thinking I should at least be able to copy everything later when I actually bother to get all the programs and have an actual green to work with, and I will probably understand everything better then.

I love the slope colours feature!

P.S. I think it is worth noting that Chambers Bay's 18th green, relatively speaking, is a VERY undulated one, both sitting on a great hillslope to begin with, and having a lot of features within it too, so Im speculating that most other greens might benefit from a finer density between contour lines, like for example 3 cm or 4 cm instead of 5 cm? But obviously that depends a lot on which course and green it is.

Thank you again for this :thumbup: :clapping:
Finished main APCD Projects: Amedal (own design), Nine Bridges (real course)
Other: Austin, Kauri Cliffs HD. Updates: Whirlpool, Royal Lytham, Royal St George's, Chicago, Chambers Bay
Working on: 2 fictional courses + a couple things...
Ian Wells
Posts: 377
Joined: Tue Aug 27, 2019 2:02 am

Re: LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by Ian Wells »

Linkster,
Thank you for the tutorial.
I have only scanned the content as I am busy trying to build Mountain Top Golf and Lake Club from the LIDAR download you kindly made for me.
After a couple of false starts I am up and "walking". Hopefully this is not another false start and I can complete the whole course.

Thanks again,
Ian
EDIT
Spoke too soon. After looking at my efforts in Links the last couple of holes I built are fine but the first couple are not so fine, and there is no way of deleting those bad holes and rebuilding them. I need to start again. :rant: :fcrossed:
Last edited by Ian Wells on Tue Aug 16, 2022 4:37 am, edited 1 time in total.
ponkey
Posts: 58
Joined: Sun Apr 05, 2020 9:28 am

Re: LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by ponkey »

Super tutorial ! Thanks a million.
I hope there's good enough data in the UK.
It would be great if you could do the tutorial about hexing the apcd too.
This method is going to be great fun !

Cheers. :cheers1:
Peter
linkster
Posts: 26
Joined: Mon Jun 13, 2022 12:12 am

Re: LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by linkster »

Thanks for the interest everyone! Here is a couple follow-ups to the conversation.

The 18th green at Chambers Bay is severely sloped and the slope map shows it. Yellow shows up at 4 percent slope and red at 10 percent. I try to avoid pins with more than 3 percent slope in Links ( 1/3 of the bottom of the break line indicator) so there is only a few places of that green suitable for pin locations. I find it amazing how well the mod green speeds match up with real life speeds and real life green slopes and how the green books and LIDAR data all work together with the ball physics in Links.

The vert density seems to play a large role in how well the LIDAR terrain matches real life terrain with soft edges in APCD. I have started to notice a big difference between 3m x 3m grids and 2m x 2m grids. Doesn't seem like much but the 2m grids pick up much more of the small details. The difference seems small but a 2m grid actually has about twice the number of verts as a 3m grid. I feel you pain Ian, I found a way to squeeze St Andrews Old Course into a 2m terrain grid and I am strongly considering a redo of my previous work. However, a trick I have learned is to draw lines for the fairway, tee, green, rough etc. edges and map a hole sized texture in APCD. This helps place the verts for the edges and then using Face Extrusions for the seam blends speeds up the process. If we all put our heads together I think there are lots of tricks we can come up with.

The APCD does not need to be hex edited to open a course with more than 100k verts, but it does need to be hex edited to import a .dem file with more than 100k verts. The process is straight forward as far as hex editing goes, open APCD.exe in a hex editor, search for the integer value of 100000, and change it to a higher number around 1 million or so. I have imported a 850k vert terrain with no problems but the plot needs to be trimmed to below 500k before saving. Something in the APCD makes it hang when trying to open a course with more than 500k verts.

APCD HEX 1.png
APCD HEX 1.png (264.44 KiB) Viewed 313 times
APCD HEX 2.png
APCD HEX 2.png (261.69 KiB) Viewed 313 times

Hey Peter, there is lots of good LIDAR data in the UK! I did 3 terrain imports for courses in the UK. If you can get some of the new 50cm LIDAR data it has incredible resolution for green contours. From my experience so far, England has the best LIDAR coverage of any area. Check out these websites for England and Scotland LIDAR data:

England - https://environment.data.gov.uk/DefraDa ... ode=survey
Scotland - https://remotesensingdata.gov.scot/data#/map

Cheers! :cheers1:
ponkey
Posts: 58
Joined: Sun Apr 05, 2020 9:28 am

Re: LIDAR Tutorial 1 – Creating Green Contours in QGIS

Post by ponkey »

Hi Linkster,
yes you are right about LIDAR in England, I've used those sites.... nothing for Carnoustie yet though.....not that I'm obsessed with that place!

A step by step guide of how you got St Andrews into APCD would be great, if you have the time.

I love the green contouring and think that will be what I'll do with Carnoustie when the LIDAR is available for that area.

Many thanks

Peter
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