|
Welcome to the Import Guide. This page and its direct links are the main point to actively participate in this buildings import. To know what the project is, its motivation and how it is developed, you can watch this short video available at YouTube.
You can collaborate through the projects published in the Task Manager. If there are no projects published in your province, you may be interested in studying how to prepare one.
In case of doubts you can ask for help through the Talk-es list, Telegram/Matrix or the forum.
Preliminary steps
These are the steps to take before you start.
- The tasks are of an intermediate/advanced level, read the documentation in these pages Buildings, Simple 3D buildings, Key:building, Lifecycle prefix and Addresses.
- Create a dedicated user account to work exclusively on imports, separate from your normal account. In the description for the account profile write that it is used for the Buildings Import described in https://wiki.openstreetmap.org/wiki/Spanish_Cadastre/Buildings_Import, source: General Directorate of Cadastre.
- Install JOSM, the recommended editor for this import, if you have not already done so.
Using the Task Manager
You can find general information about using the Task Manager in this Wiki or in the tutorial in learnOSM
- Allow use of your OSM user account in gestor de tareas clicking in login to OpenStreetMap.
- Choose a project, read the Instructions,
- Click on Contribute.
- Select a free task area manually from the map. If you are a beginner, it is advisable to start selecting tasks for which there are no buildings drawn in OSM and thus avoid the worst part of data conflation.
- Click on Start mapping.
- Click on the provided links to download the task file or open it directly in JOSM.
- Choose the proper image layers available in the Images menu: generally use PNOA, or any better regional image source, never use Bing or others (low resolution and may be displaced).
- Star now to edit the task.
Editing tasks in JOSM
Each task is formed by the set of buildings, their parts and pools within an urban block or a rustic polygon. They can contain from a single building to a hundred or two hundred. The background aerial image and the facade photos are used as support.
To show the building image, use the Point info tool in the More tools menu (Ctrl-Shift-X). Make clic in any building.
This part of the work comprises reviewing each object and following the procedure described below.
Correct problems
You have to look for problems that need editing to correct them. Read in this this section the list of possible cases and how to correct them. To keep track of which objects are reviewed or not you can follow these instructions.
- Install the TODO list plugin, if you haven't done so yet.
- Select the swimming pools (Ctrl-F, write this search term leisure=* and click on Start searching).
- Click on the Add button in the TODO list dialog.
- Select the buildings (Ctrl-F, write this search term building=* and click on Start searching).
- Click on the Add button in the TODO list dialog.
- Click on the Zoom button of the plugin to go over the first object to review.
- Did the element match with the background image? Consider deleting false buildings or moving the geometry if necessary.
- If it's a pool with the tag location=roof, is it really located over a building or inside it? If necessary change the value roof for indoor and delete the layer tag.
- If it's a building, is its use (residential, industrial) coherent with what you see in the background image and in the facade image? Consider the case when many buildings are placed in the same parcel. Maybe there is a main building with a use (residential for example), but the other could have a more precise value like garage or shed. Generally, Cadastre data includes a limited set of values, while the building key admits many more. Try to use a more precise value like apartments, detached, terrace, house. If you have doubts about the real building use change to the generic building=yes.
- If the building have tags from the Lifecycle prefix check with the facade image if they are correct.
- In the buildings, check also the building parts. Do the levels values seems to be correct? Give special attention to balconies and roofs and a possible improvement of the tagging. If you have doubts delete them.
- Buildings could have addresses tags in the way or relation that represent them or in entrance nodes. Check using your on the ground knowledge and the facade image.
- When you finish with this element, if every thing is ok click on the Mark button in the TODO list.
- Repeat the process for each element in the list.
- When the list is empty go to the next section.
Validating Cadastre data
Run the JOSM validator (Shift-V) and fix all the errors and warnings. In this phase few problems should appear .
Data conflation
In this section you will merge the data to import with the existing ones.
- To keep track of which objects are reviewed or not add to the TODO list the swimming pools and the buildings as in the previous section.
- Download the OSM data in the layer to import. If it correspond to an urban block you can do it for the whole set, if it is a rustic polygon (larger), you can download only the data around each building or pool.
- Iterate over each object in the TODO list.
- If the object to import is already drawn in OSM:
- Keep the existing building/pool if it is more detailed, copy the tags from Cadastre (levels if not present and the value of the building tag if it's more precise) and delete the one from Cadastre. If the building doesn't have building parts drawn in OSM consider reusing those from Cadastre. You should take into account that the ways for common walls must share their nodes and merge them.
- If the building/pool in Cadastre is more detailed than the existing one in OSM, replace the geometry keeping the history with the Replace geometry (Ctrl+Shift+G) option and combine their tags.
- Consider also the OSM objects placed around the object to import. Areas (such as squares or other building) must not overlap, they must share nodes for the common limits. Ways such as streets or roads must not overlap either, they must be traced over the middle of the thoroughfare surface.
- When you finish with this element, if every thing is ok click on the Mark button in the TODO list.
- Repeat the process for each element in the list.
- When the list is empty go to the next section.
Validating conflated data
Run the data validation (Shift-V) and fix those errors and warnings related to the data conflation. Those not directly related should be resolved at another time, with your normal OSM user account.
Data upload
Once all the objects in the task have been corrected and combined , you can upload it to the server remembering to:
- Check once more time that you are authenticated with the dedicated user account and not with your usual OSM account.
- In case you have used any background imagery to edit, add its name to the predefined source tag in the changeset separated by a semicolon (";"), for example "Dirección General del Catastro; PNOA".
- You can now mark this task as done in the Task Manager. Thank you for your contribution and continue with the next.
Validation of tasks
An important phase in the process of a project in the task manager is the cross-validation of tasks. In addition to the fact that each task can be carried out by an editor and marked as completed, the work will be much more reliable if it is reviewed by a different editor and marked as validated. Following the workflow defined by the manager, select a task marked as completed and click on the Validate button. Download the data uploaded to OSM in that area and check following steps similar to those for the edition phase that there is no failure. Correct them, if necessary and mark the task as validated.
|
