[Soc-2013-dev] Weekly Report #5 Mesh Data Transfer

[Campbell Barton]

On Sun, Jul 21, 2013 at 10:38 PM, walid shouman
<eng.walidshouman at gmail.com> wrote:
> //sorry for the late report got too much dragged into the code and
> since yesterday's night and I'm having a not-so-good connection
>
> = Weekly Report #5 Mesh Data Transfer=
>
> ==This Week==
> * Fixed the Shapekey Transfer Function and its working well right now
> (it's cause was passing wrong parameter to the mesh_to_bmesh transfer
> function).
> * Implemented a seam finding algorithm.
> * implemented an island finding algorithm.
> * Finished a basic algorithm for interpolation that works for
> topologies with a single island -to be extended when the whole island
> finding algorithm gets integrated with the interpolation-.
>
> ==Issues==
> * Unfortunately as expected the previous week that the UV transfer
> based on islands would be delayed a bit
> * Island finding is based on the seams_from_islands function which
> shows some bugs/unexpected output when welding edges back (should have
> turned back to a single island which wasn't the case)
>
> ==Next Week==
> * Having the whole UV Transfer function finished.
> * Debugging any found bugs for the shapekeys.
> * Discussing the Extras section with Campbell (taking into account
> that some of them were already implemented).
>
>
> wiki page: http://wiki.blender.org/index.php?title=User:Walid_shouman/GoogleSummerOfCode/2013/WeeklyReports&action=edit


Checked on these functions and am a bit worried you are moving onto
complex tasks before getting the simple/basic version working and
approved.
So far there are functions for UV and Shape-Keys, but I wouldn't
consider either finished/acceptable.

Both are O(N2), N==mesh->totvert, and I see no reason this is
necessary, It could be OK for testing the function but before moving
onto other tasks it should be resolved.

Also you could have a basic version of UV copy working first that
doesn't deal with islands, have this reviewed that it generally works
ok different methods (spacial lookups --- ray-casts, closest points
etc)

My suggestion was to start with shape keys because there is already a
Python script which you can check on, and you can use the script as a
reference if you wanted to.

For next week I would suggest you try to get either UV or Shape-Key
transfer finished, at least working on user-level with basic
functionality,
code should also not be unacceptably slow, you can use BVH tree's of
course for lookups but not have each vertex checking every other
vertex since this will grind to a halt on higher detail meshes and
really isn't needed.

-- 
- Campbell