Potlatch

From OpenStreetMap Wiki

Potlatch is a Flash-based OpenStreetMap editor, found on the 'Edit' tab of the main site.

New version! Potlatch 1.4 has been released. Intended to be the last point release before Potlatch_2, it has one notable enhancement - command "D" works like Caps Lock for dimming the foreground. These pages will be updated in time (and you can help) - but until then, check with Potlatch's online help by clicking 'Help' at the bottom left of your editing window.

The Potlatch Screen

When you first sign on to Open Street Map, typically you will see the Potlatch screen with Yahoo! aerial photography and, possibly, some mapped roads. At the bottom are some grey icons that are mapping tools and colored icons used to "tag" nodes on a map. More about that later.

You can zoom in and out using the plus "+" and minus "-" signs at the upper left of the image.

Carefully click on a "way" (a road, path or area) or a "node" (a specific spot), and it will be highlighted. Click anywhere else on the map to unhighlight it. In the example screen the highlighted road is outlined in yellow. When you highlight something, notice that the colored icons at the bottom of the screen are replaced by a kind of grid of light and dark grey boxes. You can see that these boxes contain information about the map item that you have highlighted. IMPORTANT: Look over the information but do not change anything yet until you have learned more about Potlatch.

This area at the bottom of the screen, called the Edit Panel, shows vital data about each "way" and "node" on the screen. This data is called "tags." Soon you will be adding your own "tags," but for now you need to become familiar with all the elements in the screen before you start editing.

Below the screenshot of Potlatch is a version of the Edit Panel with numbers on each element.
--1 and 2: When you select an item, this tells its basic type and its number in the OSM database
--3 through 9: These are basic tools that you will use to edit the map
--10: Template: In this case, the word "template" refers to a broad category of tags, such as "highway." "tourist" or "amenity."
--11: Relations: This refers to how each element is related to a larger road system. This is not always present on U.S. areas.
--12: Object tag: There are 7 "tags" or "object tags" in this example screen shot, starting with "highway." This element also introduces the terms "key" and "value." A "key" is a category of tags, such as "sport" or "railway." A "value" is a specific tag. For example, "highway" can be a key and "residential" is the value, or "sport" is the key and "tennis" is the value. Using multiple keys and values you can build up data for each item on the map.
--13: Delete tags: Use with caution because it does not ask you to confirm
--14: Copy tags: A handy tool for when you are making a lot of repetitive edits
--15: Open relation editor: In some cases a node or way may be part of a larger entity. For example, Historic Route 66 sometimes follows routes that today have different names or numbers. You can create a relation of the current way to the historic route. See "Relations" for other examples.
--16: Add a tag: If you need more tags to describe a way or node fully
--17: Help: a link to the Potlatch help page
--17.5?: Find Tag: A recent and welcome addition to Potlatch that provides a list of possible tags, if you are not sure which tag is right. Type in a possible tag, for example, "national park," and it provides a long list of acceptable tags for parks.
--18: Advanced menu: More editing tools. Read the Wiki for each before using them.
--19: Edit mode: Usually it is green and says "editing offline." This is the only mode a beginner should use. Make your edits, the click the next button, "Save."
--20: Save (not displayed when live edit mode): Saves changes you have made. Like anything else, the best method is to save often.
--21: Scroll bar for tags: This appears if you have added so many tags that the bottom Edit Panel is full, not likely, nor recommended, for a beginner.

After you are familiar with the screen, proceed to the Potlatch Primer [1] for the next steps.

Typical screen with Yahoo! Aerial Imagery:

Edit Panel:

Sometimes Yahoo! imagery is not available, so you will see only mapped items

Without Yahoo! Aerial Imagery:

Why Potlatch? (and why not?)

Potlatch is intended as an easy-to-learn editing environment for drawing ways and adding metadata to existing ways. It is the best way for new members to start contributing to OSM, particularly in locations where there is good aerial photography. A clear, uncluttered user interface is paramount for newer users, and the Potlatch layout draws on the familiar conventions of the existing Slippy Map.

It's not intended for power users (who are already excellently served by JOSM and Merkaartor), people who want the speed of a desktop client, or those who don't like Flash. Nonetheless, since Potlatch, Merkaartor, and JOSM are developed separately, some innovations do make their way into Potlatch first, ranging from the simple (remove a node from one way alone) to the complex (editing history). An increasing number of experienced OSMers use Potlatch as a supplement to JOSM for instant editing, and a few use it as their principal editor.

As a very rough rule of thumb, Potlatch is easier for quick edits, and better for edits which range over a wide area (e.g. cycle routes). JOSM is better for heavy-duty editing in a concentrated area (e.g. housing estates) and offers facilities for audio and photo surveying. But everyone will have their own preferences.

See also

• Comparison of editors
• OpenStreetMap component overview
• Potlatch blog
• Localizing potlatch on Translatewiki
• Potlatch Cheatsheet
• Potlatch/Keyboard_shortcuts