Feature Request: Make manual entry of lat-long more obvious

[richb-hanover]

I created a report (#182) because, as a newbie to Mapwarper, I didn't realize how to enter lat-long manually for the control points. I was confused by the GUI - I didn't understand what I was seeing. Here is what ran through my mind when I first saw the Rectify page after importing my PNG file:

1. I saw my image on the left, and the world map on the right. I wondered why the world was shown there.
2. I saw the instruction to double-click both maps, but didn't realize what else I was supposed to do.
3. As noted in #182, I didn't see a way to enter my lat-long info.
4. I worried about how much I would have to learn to create a map successfully.

I have been speculating what might have "un-confused" me. Let me make a few suggestions:

1. The page needs a little more explanation of the process. Instruct the viewer that they need to create several control points and then click the "Warp Image" button.
2. I think the instructions should distinguish between Automatic and Manual control point creation. It's almost as if radio buttons could control whether Automatic or Manual instructions are shown (the other would be hidden).
3. For Automatic: the instructions could say:

Automatically create control points: Zoom both maps above (left and right) to show the same locale. Then press "1" (to select the "Add control point" tool) and click the matching locations on each map. Then click the "Add Control Point" button. This locks the X&Y location on the left to the longitude and latitude of the world map on the right. Do this for at least three points on the map.

4. For Manual, the "Automatic" text would be hidden, and maybe hide the OSM map on the right, as well. An (initially empty) Control Points list would appear. The text could say:

Manually create control points: Press "1" (to select the "Add control point" tool) and click a point on the image. Then click the "Add Control Point" button, and enter the known longitude and latitude for that point in the list below. Do this for at least three points on the map.

5. I think you can then get rid of the "Add control point manually" button. People could simply switch to Manual, create a new control point, and edit the image X&Y as well as long-lat manually.
6. I would be tempted to move "Add control points from CSV", "Download points as CSV", and the Map Mask options into the Advanced Options, since I suspect they are less frequently used.

I apologize for the length of this note, and I want to say how powerful this tool is. Thanks.

[timwaters]

Thanks for the issue. As your comment indicates, the instructions are quite lengthy. Where to put these on the interface is another issue, both are not simple things to resolve.

Did you look in the help page? Maybe thats where this should go.

Pull requests are open if someone else encounters this and has a solution

[richb-hanover]

OK. I am taking up your challenge. :-) I crocked up a potential GUI in a paint program. The three images show:

1. Automatic mode - letting people set the lat-long of the control points from corresponding points in the world map
2. Manual mode - letting people set the lat-long for control points by typing them in
3. Advanced options - put all the rest of the controls in a separate place, hidden by the disclosure triangle.

I intended that these changes are mostly a re-arrangement of items that are already present. With the exception of adding some text blocks for the instructions, I hope that not much needs to be modified.

Thanks for considering these changes!

Automatic Entry: Show both maps, with instructions for clicking the "same point" in each.

Manual Entry: Hide the world map (on the right) and show the current (possibly empty) list of control points.

Advanced Options: Whether Automatic or Manual is selected, the disclosure triangle can be clicked to show all the options.

[richb-hanover]

Update: I found my original report, and provide this updated description so I remember how to enter points manually...

Manually create control points:

• Press "1" (to select the "Add control point" tool)
• Click the desired location on the image on the left; click anywhere on the map on the right.
• Click the "Add Control Point" button. This will create a manual entry, with the X/Y position of the control point on the left, and (bogus) data into the Long/Lat fields
• Enter the known/correct longitude and latitude for that point in the Long/Lat fields.
• Do this for at least three points on the map.
• Click Rectify to "warp" the map to these coordinates