Hello again,
I am back with my old problem:
where to get the best Mars hightmap and how to use it?
The best planetwide map I can find to date is that one:
https://astrogeology.usgs.gov/search/map/Mars/Topography/HRSC_MOLA_Blend/Mars_HRSC_MOLA_BlendDEM_Global_200mp_v2200 m per pixel for a whole planet, thats a lot of pixels, 11,4 gb of them actually. The biggest maps I can load into TG on my computer are 2 gb.
So I can use parts of that map, so far so good.
Now there are two problems:
1- the map appears to be "partially inverted" meaning the lower half is brighter thann the upper half, but inside each half the greyscales are in the right order, so I cannot simply invert it. Hard to explain. where the greyscales representin hight should be 1-2-3-4-5-6-7-8 they are 5-6-7-8-1-2-3-4?
I tried a lot of tricks in photoshop, making masks to adjust the displacement, and it works quite, but there are always strange artefacts, pixel sized in the best cases, along the border.
Any ideas?
2 may be easier:
how can I place my partial maps on the planet?
using a planetwide equirectangular map is easy, project it spherically and there you go. But how can I put a quarter, or some rectangle from the middle of that map on top of a lowres planetwide map in the right place?
Thanks in advance,
would be great if somenone could help.
Best Regards,
J