[Bf-committers] Prospective GSOC [Harshit Mehta]

[Harshit Mehta]

Hello everyone,

I am using blender since last two years. Before that I was onto Autodesk
Maya (student version). This winter I got chance to download blender code
and build it. I tried it on windows with MSVC9 following wiki. Since then I
am trying to get myself familiar with source code. Recently I am also
trying to solve few bugs. That's for my introduction. Now I turn to my main
purpose of contributing Blender through GSOC 2014.

I am writing this mail to get feedback on my ideas for proposal. I wish to
modify decimate modifier by adding a brush facility to selectively reduce
meshes.

1**. One could adjust brush size (part of mesh under impact) as with other
brushes. Decimate need to be operated in edit mode then.

2**. Use of brush strength parameter -
With lower brush strength, only edges (low cost) with lengths below certain
threshold will get collapsed. Other low cost edges will only get shortened.
If artist feels edge shortening doesn't affect mesh shape largely he can
with subsequent brush applications get edge collapsed.
So in nutshell there would be a length threshold below which edges will get
collapsed. As brush strength increases, this threshold will also increase.

3. Symmetric reduction by specifying plane of symmetry
 It would be useful for human body like meshes. Apply reduction on one half
and other also gets mesh-reduced. Symmetry could also be made to be
calculated without POS specification. This option would be manifested as a
check-box.

4. Within current edge collapse, option could be added to replace edge with
its midpoint instead of moving one vertex to another. Again that would be
more useful for symmetric objects. I doubt unsubdivide would also give
similar results. So may not be much of new addition.

5. I would love to try implementation of  hoppe's energy criterion for edge
(to be collapsed) selection instead of cost factor (length * curvature).
This would also take into account contributions of texture coordinates,
border edges, and surface discontinuities and select as per lowest energy.

Maybe, addition of all above features along with existing ones will create
a lot of clutter in decimate section. I wish to completely separate brush
implementation from existing one and add point 3,4 and 5 (ones which
finally turn out worthy) along with current collapse, un-subdivide and
planar.

I understand what i have stated above would be much less for a typical GSOC
project. I also have plan for adding a new modifier but am currently in
search for its implementation techniques. As soon as I figure out
sufficient about it, I will write back again. My purpose of writing this
mail was only to get feedback on my ideas on decimate modifier.

Thanks for going through my mail. I am wait eagerly for feedback from
developers.

Harshit Mehta
Email: harshitmehta2293 at gmail.com
Phone No: +918058412102
IRC nick: Harshit22