Gerhardus Geldenhuis's Diary Comments

Diary Comments added by Gerhardus Geldenhuis

Post When Comment
Editing on steroids? about 9 years ago

Hi skorasaurs, The tool you mentioned is called “Improve Way Accuracy”. Firefishy introduced me to it and I can’t manage without it any more. You can also use Shift to lock the node you want to move, I find it useful when there is a large number of nodes in a small area.

I’ll work through the Advanced Tricks page.


Editing on steroids? about 9 years ago

Thanks Vincent! The trackball is a great idea I am going to try that out.

Did you meant to type straightforward plugin? If so I will give it a go too.

I have tried one of the lakes plugins but could not get it to work and it is not great. It would have been brilliant if one could integrate something like ENVI with JOSM. I also think that JOSM should more easily make available settings of various tools. For example the simplify tool to customize the parameters. It would make it a lot easier to experiment with various options.

I’ve not used the search functionality as you suggest but I do activate a filter while editing rivers for example which only shows rivers and new data, making it a lot easier to work with. There is also a shortcut that I used to select all nodes which I have momentarily forgotten which is very useful to set power=tower on a long power line.

I have been mapping a lot of rivers and riverbanks lately as well as power lines, which means a lot of scrolling in which case I think the trackball suggestion would be good to try out. I have also recently did a lot of buildings in the Philippines for which I used a buildings plugin which is very handy.


Quality of river mapping about 10 years ago

Thanks HeBri, the imagery you mention is the CD:NGI imagery I referred to.

Severe flooding about 10 years ago

I agree that the normal river bank should be tagged and should be the one that gets displayed. However I believe OSM is about more than just a pretty map and a potentially very powerfull future data source and in that regard it would be useful to have more river bank information.

JOSM about 10 years ago

Yes, I have already reached that step. I can’t imagine why I have not done it sooner. I can’t seem to convince JOSM to make multiple holes in a polygon, one yes but not multiple but I will figure it out. The caching of imagery means I can be a lot more productive, I have yet to figure out how to download all zoom levels for a chosen area.

I also love the display as it really clearly shows were I have been and what areas I am busy with. I have some suggestions for improvements but will live with the editor a little while longer before making them. Mainly it would be nice to have the frequently used tags be persistent after program restart and the ability to single click select the frequently set tags rather than the 3 clicks it currently takes.

Dyke? over 10 years ago

Hi Alexz, The Vaal Barrage is still very much standing and is further east from the location we are discussing. It has 9m high sluice gates that can be lifted completely out of the water to let water through. 1996 was the only year that I saw all of the gates completely lifted out of the water. Normally if you lift one of the gates 2m it causes significant rise downstream and the police drive from resort to resort warning the fishermen. If you are lucky and get permission to go on the Barrage while they open a sluice gate you might sometimes see very big catfish swimming in the stream of water gushing out from underneath the sluice gate. They hover there to catch smaller fish that got sucked in.

Your comment about the impact crater reminded me that one of my friends has spend several weeks mapping parts of the crater close to the town of Parys. She is much more familiar with the geology and I have asked her for an expert opinion.

I have extended your trace slightly to the south east and added two more traces to the north east and south west of your trace for illustration purposes of other similar features.


Dyke? over 10 years ago

Hmmm, I gave your suggestions serious consideration. I compared the Google Maps images, the South Africa CD:NGI Aerial and the Bing imagery to be sure. What convinces me that it is geological rather than the remains of a road or railway is the following: * It’s only visible in the vicinity of the river, if it were a road or railway I would have expected it to be visible a lot further away from the river.

  • It forms a prominent ridge and casts a shadow in some places in the Bing imagery which would support it being a natural ridge rather than a old road.

  • The vegetation is more dense and differently coloured on these features which would suggest a difference in soil and thus underlying geology. If it is such an old road then it is unlikely that there were money or equipment to bring in “foreign” rock and material from other areas to build the road/railway which could account for the difference in vegetation.

  • The “lines” cross the river twice in short succession. By moving the it slightly north you could have build only one bridge. I am generally fairly optimistic about the level of intelligence of railway engineers that build South African railways and I don’t think they would have made such a mistake.

All that being said I would still be open to convincing otherwise. I do think it is rather academic at this stage as it is not worth mapping for OSM and would require a site visit to be sure. I will try and visit the location when I am in South Africa in January.