Hi List,
Another bitmap export issue - might just be a bug in MI tho.

I am using UTM projection. I have my map window square on the screen
(500x500px) and view set to 270,000 metres East 5,110,000 metres North
and 10km across the map. If I then save the map window as a
10,000x10,000 pixel png, it does not export the bitmap correctly.

There are a couple of reasons it's not exported correctly.
1. The bottom left corner grid ref should be 265,000E, 5,105,000N (5km
south east of the center of the map). But it is actually 264,997E
5,104,997N. This does not seem much, but when trying to align with an
adjacent tile it is really noticable.

2. There is a white line at the bottom and right edge of the bitmap.
Investigation shows this has overlayed the map - a bug?, but not 100%
sure. I've turned off exporting the border BTW.

3. Measuring two known points at east and west extremities (same
northing) of the map indicate that the exported map is not actually 10km
wide, but actually more like 9.996km - so it's ended up squashed!

I was hoping to use this export method to create several adjacent
10x10km tiles that I could export into another rendering engine (which
needs maps in this 10k x 10k png format), but they don't line up due to
MI not exporting correctly. Like I said before, I know it's only a few
metres here-and-there, but it looks awful at the join, and it's the
difference from making it look like you're driving on the right/wrong
side of the road!

Is there a known issue with the accuracy of the 'save window as' option
(the strange white lines at the right and bottom edge worry me)?

Hope someone knows what's going on.

Cheers

Tim

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