"North" direction on maps needs to be updated for 1.9pre4/release 1.0.0

As of 1.9pre4, and in the final release, it seems the sun and moon were changed to rise in a different direction. This means that if we still use them to define east and west, then the direction that used to be called "north" is now "west". If I generate a map with north_direction = 'upper-right', the map is actually generated with the new "north" pointing to the lower right. Will the north_direction option and the compass rose be updated to match the new definition of directions?

[CounterPillow]

As there are many servers which have not yet updated to 1.0.0, it wouldn't be a good idea to already update it as it would cause major headaches for server admins. Maybe we should update it so that on a fresh render, the map would be rotated differently, and maybe print out a little notice.
The process of changing the code to use new directions shouldn't be too hard, as it mainly involves changing code comments and renaming the options. :)

Good point; what about adding a new option like "use_old_north" that defaults to true?

[CounterPillow]

That's not a good idea as overviewer already has many options, and this one will just clutter the docs and will be deprecated really soon.
But I barely develop anything on overviewer, this is just my own opinion.

[brownan]

A use_old_north may be our only or best choice, even though I dislike adding new options unless necessary. My first thought is that we could just re-name the option to "west direction" and call it a day.

If we wanted to continue to call it north-direction, people would have to change their configuration to have their maps continue to point in the same direction.

How about this: We change the meaning of the north direction option, which will break people's configs. However, if the overviewer.dat has recorded a different direction, we don't fail, but just print a warning and render with the same orientation that it was.

[CounterPillow]

@brownan: I like your idea. Maybe we should solve this with the overviewer.dat, maybe after rendering the old direction, update it with the new direction it would be for that orientation. I'm not sure though how we'd detect whether it's an old or a new direction - maybe a new value that is written into overviewer.dat.

[brownan]

exactly. We can solve this by adding a new value to the overviewer.dat. Since that file is opaque to users, they don't have to do anything but pay attention to the warning we print when they haven't updated their configs. The first run would change the overviewer.dat north direction to the proper one and add a boolean "updated_north_direction = True" or something.

[agrif]

We've done this sort of automatic-update business before with overviewer.dat, and it's a little bit tricky. It'd be a lot easier if the dat file was versioned somehow, like with a 'version' key.

[tswsl1989]

A version key seems sensible, as any compatibility checks can be kept in one place under an if/select on the version number to perform any updates.

We're bound to run into incompatibilities in the future - either due to minecraft updates or updates to overviewer itself.
Might be possible to tie into the version used for the extension? Not sure how that's set/generated at the moment though.

[brownan]

I don't think it'll be tricky.

• User renders a map without an overviewer.dat - first render ever, no previous render to worry about. Render with the direction they actually requested. Write that direction to overviewer.dat and set updated_north_direction to True
• User renders a map with an overviewer.dat without updated_north_direction set - first render after update. Take the north_direction from the file, rotate it to the right, and pretend that was what's actually in the file. Proceed with the render as normal using the (adjusted) direction from the dat file. At the end, write out the adjusted north direction and set updated_north_direction to True. Print a warning to the user if the requested north direction doesn't match the adjusted north direction.
• User renders a map with an overviewer.dat file with updated_north_direction set - Render the map with the north_direction from the file. Print a warning to the user if the requested north direction doesn't match the rendered north direction.

Edit: A version key in the file would work the exact same way, just check if the version key exists and is at least a certain number instead of the existence of that flag.

[agrif]

Edit: A version key in the file would work the exact same way, just check if the version key exists and is at least a certain number instead of the existence of that flag.

That's what I was thinking. A version key would also lead to less clutter in the future if something like this happens again.

[brownan]

Then it's settled, that's what we'll do. Now someone just needs to do it. We really should have been working on this beforehand... we knew it was coming =)

[Fenixin]

I'd like to throw another idea for the north variable in the code:

At the moment we are using text string for the option north direction. It seems that Minecraft uses a number for every direction (Minepedia do that also), so, for Minecraft version 1.0.0, north is f=2, you can see the direction be pressing the F3 key in game. This numbers are probably harder to change than the position in the sun in Minecraft. We can change the north varialbe in overviewer's code to direction-in-upper-left-corner and make it contain the number that uses Minecraft for that direction. In this way overviewer would be more independent of sun-rising changes. Not sure if it's worth the change, the sun isn't probably going to change once more his rising direction.

Users don't have to worry about this, the option --north-direction can be kept and overviewer can do all needed conversions.

Please, tell me what you think.

[agrif]

I'd love to turn north-direction into an integer. Right now there are a ton of string comparisons all over the place, and those are easy to mess up. IMO it's one of the last bits of unnecessarily ugly code left in textures.py.

[ardichoke]

Has the fix for this been merged into master yet? If not, is there any eta on when it will be?

I have an Overviewer map for a community server that I run. I have the north direction set to upper right. Overviewer is rendering the west to the upper right, however, but putting the compass the way I requested. This is causing some confusion for the players. The render was done with a fully updated Overviewer as of today and is a completely fresh render of a world that was generated with 1.1 on Saturday.