Sketch Classes
In SeaSketch, sketch classes are the things you draw, such as zones, and potentially analyze as prospective plans.
Last updated
In SeaSketch, sketch classes are the things you draw, such as zones, and potentially analyze as prospective plans.
Last updated
Adding Sketch Classes
To add a sketch class click the "Add +" button. Sketch classes include Simple Polygons, Simple Lines, Marine Protected Areas and Collections. Collections are just as they sound like: collections of multiple sketches that can be analyzed as a whole. This is not to be confused with a simple folder which is just a bucket to hold muliple sketches or collections but cannot be analyzed. We cover creating folders in the End User Documentation.
Simple polygons could be any zone type, for example an "mariculture zone". The settings tab allows you to give it a name and limit who sees it (using Access Control).
After creating and using your sketch class, you may wish to hide it. Perhaps you no longer have a use for it and you don't want to confuse your users by having it persist in the Project. If this is the case, toggle the Archive to "on". You can always restore it in the future.
You may also choose to delete a sketch class but this is only possible if your users have created fewer than 10 sketches. This is to prevent "orphaned" shapes they may have drawn.
Create as many attributes for a sketch that are useful. Possible attribute fields include:
Multiple Choice (multiple or single selection)
Short Text
Text Area
Number
Rating (1-5 stars)
Statements (which can provide information to users)
Combo Box (similar to Multiple Choice but presented in a dropdown list).
Matrix
Notice that for any given attribute, you can edit the options associated with it by clicking the pencil icon next to the attribute in the form. In the example below, the Multipe Choice options include Required (on/off), Export ID (the column name used when exporting data), Change to Comobo Box and Options (for labels and values).
A sketch can be configured with a preprocessing service and geoprocessing service. A preprocessing service is used to transform or validate a sketch, for example erasing land from a polygon intended to overlap water or ensuring a zone falls within a nations exclusive economic zone (EEZ). A geoprocessing service defines the reporting tools that will appear when analyzing a sketch, such as calculating the amount of overlap with seafloor habitats or human activities.
Services are used by entering the URL of that service. For example, the following URL is a preprocessing service that removes land from a sketch using the Open Street Map land polygons:
Simply enter the above URL into the preprocessing service of your simple polygon
Click "Search"
And then choose the preprocessing service you would like to use. In this case, the name of the preprocessing service si called "eraseLand", a service thag was written by Chad Burt on May 5, 2020.
Geoprocessing services that are used to analyze sketches and generate reports are significantly more complicated to add. This is because, at the time of this writing, we do not have generic geoprocessing services you can use. These services must be written using our Geprocessing Framework which is documented here on GitHub.
We have an Application Programming Interface (API) that will allow 3rd party developers to create their own geoprocessing services and reports, then link them up to sketch classes in their own project. Our hope is that, over time, 3rd party developers will create custom reports and publish them as open source, creating a library of templates that could be used by others.
The style editor for Sketch classes is currently code based and uses the Mapbox GL Style language. In the near future, we will also have a graphical user interface (GUI) for modifying styles.
